Code of Hydraulic and Sanitary Installations in BuildingsCódigo de Instalaciones Hidráulicas y Sanitarias en Edificaciones

The objective of this Code is to establish the minimum requirements to protect public health, safety, and general welfare in buildings intended for human use, occupancy, or habitation and that are constructed in the territory of the Republic of Costa Rica.

This Code must be complied with during the stages of design, construction, installation, repair, retrofitting, replacement, relocation, addition, or remodeling of buildings.

This Code covers the sanitary and hydraulic installations of drinking water (cold and hot), wastewater drainage (desagüe de aguas residuales), venting of sanitary installations, stormwater drainage, and LP gas distribution, all related to buildings.

Due to their nature, the sanitary and hydraulic installations and LP gas must be designed, constructed, installed, repaired, replaced, or remodeled using proven methodologies and techniques, as well as materials of proven capacity. However, the use of alternative materials and design methods not specifically indicated by this Code is not limited, provided that the design professional responsible demonstrates that the use of the alternative allows for compliance with the objectives described in this Code.

Regardless of the degree of refinement in the analysis and design, or the quality of the materials, or the construction, it is necessary that all installations for which this Code establishes standards be well conceived and planned, in order to achieve the established objectives.

The provisions contained in this Code represent minimum requirements in pursuit of adequate performance of the installations. However, the work of the design professional responsible must not be limited to the unthinking compliance with these provisions, but must seek the satisfaction of the objectives established in the Code and adopt, if necessary, alternative criteria more rigorous than those established by this Code.

This Code makes reference to provisions of other national and foreign codes and standards. It is understood that the Code refers specifically to the versions in effect at the time of the final revision of this document, in the month of January 2017.

However, the design professional responsible must keep in mind the reforms and changes to said documents subsequent to this date, in strict adherence to their best professional judgment and the ethics rules established by the Colegio Federado de Ingenieros y de Arquitectos de Costa Rica (CFIA).

2. DEFINITIONS

For the purposes of this Code, the following terms have the meaning indicated in this chapter:

- A - Supply (pipe) (Abasto (tubo de)): pipe, generally flexible, used to connect a toilet, lavatory, sink, or other sanitary fixture (accesorio sanitario) to the main drinking water supply.

Service connection (Acometida): connection of a specific building to an established system or service.

Water for industrial use (Agua para uso industrial): water not necessarily potable, whether due to its physical, chemical, or biological characteristics; its expected quality will depend on the needs to be met in each case.

Water for reuse (Agua para reutilización): water usable in any distribution system, except for the drinking water distribution system.

Recirculation water (Agua de recirculación): water with quality equal to or greater than that of the system where it is supplied.

Drinking water (Agua potable): water that meets the physical, chemical, and biological characteristics that make it suitable for human consumption, in accordance with the provisions of the World Health Organization on the quality of drinking water.

Wastewater (Aguas residuales): water containing waste, materials in suspension or solution of human, animal, vegetable, or chemical origin, coming from discharges from residences, commercial buildings, or industrial facilities of any kind; it is classified into two types: ordinary (ordinaria) and special (especial).

Special wastewater (Agua residual especial): wastewater of a type different from ordinary; for example, water from industrial or hospital processes.

Ordinary wastewater (Agua residual ordinaria): wastewater generated by domestic activities of human beings (use of toilets, showers, lavatories, sinks); unless otherwise indicated, when this Code refers to wastewater, it is of this type.

Storm sewer (Alcantarillado pluvial): public or private network of pipes used to collect and transport rainwater to its point of discharge into a receiving environment.

Sanitary sewer (Alcantarillado sanitario): public or private network of pipes used to collect and transport wastewater to its point of discharge into a receiving environment.

Sanitary fixture (Aparato sanitario): device generally connected to a water supply system (potable or not), which receives it without danger of contamination and discharges it to a wastewater drain pipe after use.

Fixtures for private use (Aparatos de uso privado): those intended for use by a restricted number of people, for example in family residences, commercial buildings, hospital, or industrial buildings.

Fixtures for public use (Aparatos de uso público): those located so they can be used without restrictions by any person; these can be found in public institution buildings, commercial buildings, temples, stadiums, recreational centers, among others.

Administrative authority (Autoridad administrativa): entity in charge of administering and operating the public aqueduct and sewer systems (AyA, municipalities, or others).

Health authority (Autoridad sanitaria): public entity in charge of establishing sanitary standards and laws regarding water quality, as well as the characteristics and requirements of effluents (Ministerio de Salud).

AyA: Instituto Costarricense de Acueductos y Alcantarillados.

- B - Stack (Bajante): pipe in a wastewater or stormwater drainage (desagüe) system.

Battery of sanitary fixtures (Batería de piezas sanitarias): any group of similar and adjacent sanitary fixtures (piezas sanitarias), which share the same water supply pipe and discharge into the same waste branch (ramal de desagüe).

Cleanout (Boca de limpieza): part or accessory that forms part of the drainage pipes (tuberías de desagüe), intended to allow inspection and cleaning of said pipes.

Bidet (Bidé): sanitary fixture intended for the cleaning of the intimate parts of the body.

- C - Inspection chamber (Caja de registro): plastic, metallic, or concrete structure intended to allow inspection, cleaning of drainage pipes (tuberías de desagüe), capture sludge and solid objects; it also allows for changes in direction, slope (pendiente), diameter, and pipe material.

Flow rate (Caudal): volume of liquid or fluid passing through a section of pipe or channel per unit of time; in this Code, it is usually expressed in liters per second.

Flow meter (Caudalímetro): see water meter (hidrómetro).

CFIA: Colegio Federado de Ingenieros y de Arquitectos de Costa Rica.

Cistern (Cisterna): see capture tank (tanque de captación).

Sewer (Cloaca): see wastewater or stormwater collector (colector de aguas residuales o pluviales).

Stormwater collector (Colector de aguas pluviales): main pipe intended to collect and convey rainwater from a building to the connection with the storm sewer (alcantarillado pluvial).

Wastewater collector (Colector de aguas residuales): main pipe, intended to collect and convey wastewater from a building to the connection with the sanitary sewer (alcantarillado sanitario).

Condominium (Condominio): property constructed in a horizontal, vertical, or mixed form, susceptible to independent use by different owners, with common elements of an indivisible nature; these latter, called "common goods," are those elements, belongings, or services of inalienable and indivisible domain of all owners, necessary for the use, safety, health, conservation, access, recreation, or ornamentation of the property.

Cross-connection (Conexión cruzada): physical connection between two piping systems, where water can flow from one system to another, depending on the direction of the flow and the differential pressure between the two systems.

Residential water connection (Conexión domiciliaria de agua): section of pipe between the public drinking water pipe and the meter located outside a building.

Residential stormwater drainage connection (Conexión domiciliaria de desagüe pluvial): section of pipe between the last inspection chamber (caja de registro) and the storm sewer (alcantarillado pluvial).

Residential sanitary drainage connection (Conexión domiciliaria de desagüe sanitario): section of pipe between the last inspection chamber (caja de registro) and the sanitary sewer (alcantarillado sanitario).

Consumption (Consumo): flow rate measured at the residential drinking water connection.

ASME-type container (Contenedor tipo ASME): container built in accordance with the code and specifications of the American Society of Mechanical Engineers (ASME).

Cylinder-type container (Contenedor tipo cilindro): container designed, constructed, tested, and labeled in accordance with the specifications of the United States Department of Transportation.

Vent stack (Columna de ventilación): pipe intended for the entry or exit of air from the drainage system (sistema de desagüe) of a single or multi-story building.

Bathroom (Cuarto de baño): room where sanitary fixtures (piezas sanitarias) intended for personal hygiene are located.

- D - Demand (Demanda): consumption of drinking water for a given time interval, for a given purpose, in a building.

Effective diameter (Diámetro efectivo): inside diameter of a pipe.

Nominal diameter (Diámetro nominal): commercial or standardized dimension of pipes, which does not necessarily correspond to the effective diameter.

Gas connector device (Dispositivo conector de gas): assembly formed by a flexible or semi-rigid pipe and accessories, responsible for conveying fuel gas (gas combustible).

Quick-disconnect device (LPG) (Dispositivo de desconexión rápida (GLP)): manually operated device that provides, for equipment or an outlet connection, a means of connecting and disconnecting the gas supply, which is equipped with an automatic means of disconnection to shut off the gas supply when the device is disconnected.

Supply rate (Dotación): measure of consumption or demand usually expressed in liters per person per day or its equivalent for a building, according to the use and occupancy for which it is intended.

Indirect waste (Desagüe indirecto): discharge from a sanitary fixture or any other device that is made through an air gap to the drainage system (sistema de desagüe) of a building, by using a floor drain or other suitable device.

Mechanical duct (Ducto mecánico): hollow space left in buildings, of regular section (e.g., rectangular or circular) and generally bounded by walls; it is used to house pipes from electromechanical systems or ducts from ventilation and air conditioning systems, in order to allow their inspection, repair, or maintenance.

- E - Building (Edificación): any construction or building intended for use, occupancy, or habitation by people.

Runoff (Escorrentía): rainwater that flows over the surface of a terrain.

- F - Filtration (Filtración): physical separation of solid substances in suspension in a liquid through the use of porous media.

Filter (Filtro): device or apparatus with which the filtration process is carried out.

Float valve (Flotador, válvula de): device that is maintained on the water surface of a capture tank (tanque de captación) and is generally used to record level variations or to govern a switch or a valve.

Flushometer (Fluxómetro): semi-automatic valve that discharges a specific volume of water to evacuate a quantity of liquid from a sanitary fixture (inodoro or urinal); it is usually activated by a lever, button, or electronic sensor.

Leak (Fuga): loss of liquid due to lack of watertightness in tanks, pipe fittings, sanitary fixtures, or others.

- G - Fuel gas (Gas combustible): term referring to liquefied petroleum gas (LPG, LP Gas, Propane, Butane, among others).

Water hammer (Golpe de ariete): pressure variation that a pipe and its accessories undergo due to the effect of sudden changes in water velocity.

Energy gradient (Gradiente de energía): rate of change of the energy line, which describes the sum of the elevation head, the pressure head, and the velocity head.

Hydraulic gradient (Gradiente hidráulico): the rate of change in the hydraulic grade line, which represents the sum of the pressure head and the elevation head; usually expressed in units of length above a reference level.

- H - Water meter (Hidrómetro): device or instrument used to measure flow rate (caudal).

Hydropneumatic (Hidroneumático): see hydropneumatic tank (tanque hidroneumático).

- I - Sanitary installation (Instalación sanitaria): set of pipes, equipment, or devices intended for the supply and distribution of water, and for the evacuation of drains (desagües) and their venting within the building.

Gas installations (Instalaciones de gas): term referring to any tank, container, regulating equipment, meters, and accessories necessary for the storage and distribution of fuel gas (gas combustible) for any building or premises.

Float switch (Interruptor de flotador): float equipped for the control of a pump or other equipment, whose operation is linked to the variations in the level of a liquid in a tank.

Vacuum breaker (Interruptor de vacío): mechanically acting device intended to prevent backflow (reflujo) of water.

Interceptor (Interceptor): device designed and installed to separate and retain undesirable or hazardous materials that may be contained in the wastewater (aguas residuales) of a building, allowing, in turn, the gravity drainage of said water to the drain pipes (conductos de desagüe).

Grease interceptor (Interceptor de grasa): device used to effect the separation of grease and oils in the discharges from establishments where food is prepared; such devices may be of the type intended for outdoor placement, or located near the sanitary fixture; also known as grease trap (trampa de grasa).

- J - Open joints (Juntas abiertas): joints that are not hermetic and that allow a separation between the pipes that form them.

Flexible joint (Junta flexible): allows slight displacements or rotations of a pipe to absorb vibrations or stresses from external loads, as well as the effects of transient regime situations in the system.

Seismic expansion joint (Junta de dilatación sísmica): accessory used in piping systems to cross seismic joints between structures or to enter from the exterior to the interior of the building; it is an extremely flexible joint, with movement in all directions to prevent breakage in the event of a seismic event.

- L - Purge valve (Llave de purga): valve that allows draining water or sediments from a pipe or container.

- M - Water meter (Medidor de agua): see water meter (hidrómetro).

Calculation report (Memoria de cálculo): written report complementary to the project plans and explanatory of the determinants of its operation.

mca: acronym for the pressure unit meter of water column or water head (metro de columna de agua); one (1) mca is equivalent to 9806.65 MPa at 4 °C.

- N - Overflow level (Nivel de rebalse): the level corresponding to the discharge of excess water entering a capture tank (tanque de captación) or sanitary fixture (pieza sanitaria).

- P - PE: common acronym for polyethylene, in both English and Spanish.

PEAD: common acronym for high-density polyethylene (acronym in English HDPE).

Head loss (Pérdida de carga): the variation in height of the hydraulic grade line, that is, it is equal to the change in the sum of the pressure and elevation heads; it originates from the energy dissipation caused by the friction of the fluid as it flows through a pipe, and is equivalent to the terms "head loss" or "pressure loss." Service pressure (Presión de servicio): the static pressure at the entrance of a piping system in its normal operating regime.

Dynamic pressure (Presión dinámica): corresponds to the term of kinetic energy per unit volume.

Static pressure (Presión estática): the value of the pressure in a piping system under zero flow conditions; it can be considered invariant over time.

Stub-out (Prevista): pipes and accessories normally placed over the main pipes of water supply or sewer networks, with the purpose of being used for the sanitary installations of future users.

Simultaneous use probability (Probabilidad de uso simultáneo): probability that a certain number of sanitary fixtures (piezas sanitarias) are used at the same time, at any given moment.

PVC: acronym for polyvinyl chloride.

- R - Supply branch (Ramal de alimentación): pipe that supplies water to a sanitary fixture or a group of them.

Discharge branches (Ramales de descarga): pipes that directly receive the effluents from sanitary fixtures.

Waste branches (Ramales de desagüe): pipes that receive the effluents from the discharge branches (ramales de descarga).

Overflow (Rebalse): pipe or device intended to evacuate eventual excess water in storage tanks, sanitary fixtures, or other sanitary accessories.

Public network (Red pública): pipe of the public aqueduct distribution system or the public wastewater or stormwater collection system.

Backflow (Reflujo): flow in the opposite direction to that intended for a pipe or sanitary fixture.

Access opening (Registro): opening for inspection or cleaning of tanks or pipeline routes.

- S - Water seal (hydraulic seal) (Sello de agua (sello hidráulico)): volume of water existing in the trap (sifón) of a sanitary fixture that prevents the backflow (reflujo) of gases, odors, and the entry of animals from the discharge pipe into the fixture.

Separator (Separador): see interceptor (interceptor).

Trap (Sifón): accessory whose function is to maintain the water seal (sello de agua) in the discharge of sanitary fixtures.

Trap seal loss (Sifonaje): breakage or loss of the water seal (sello de agua) of the trap (sifón) of a sanitary fixture, as a result of the loss of the water contained in it due to the effect of positive or negative pressures in the drainage system (sistema de desagüe).

Direct supply system (Sistema de alimentación directa): water supply to the consumption points of a building directly by the service pressure of the public network, when its minimum values are adequate to continuously satisfy the hydraulic requirements of the subscriber's installations.

Indirect supply system (Sistema de alimentación indirecta): water supply to consumption points that does not directly use the service pressure of the public network.

Single stack drainage system (Sistema de bajante único de desagüe): single-pipe drainage system (sistema de desagüe) in which all or almost all vent pipes (conductos de ventilación) are omitted.

Hydropneumatic system (Sistema hidroneumático): system that supplies water under certain pressure conditions to the distribution pipes, by means of an energy accumulator through air compression; it is generally composed of a pump and a hydropneumatic tank (tanque hidroneumático).

Constant pressure system (Sistema de presión constante): system that supplies water under certain pressure conditions to the distribution pipes by means of a pumping system; it is generally composed of an arrangement of pumps with a variable frequency drive and a pressure sensing system.

Reuse system (Sistema de reutilización): system that conveys water to be reused within a building.

Drain (Sumidero): sanitary accessory (accesorio sanitario), with or without a hydraulic seal (sello hidráulico), intended to receive wastewater (aguas residuales) or stormwater from the floor of a bathroom, patio, or roof.

- T - Capture tank (Tanque de captación): drinking water tank from which the sanitary fixtures of the buildings are supplied; it can be elevated or buried, depending on the space available for the building.

Elevated tank (Tanque elevado): capture tank for water storage located on the upper floors of a building or on a structure designed for that purpose.

Hydropneumatic tank (Tanque hidroneumático): reservoir in which water and air are stored under pressure.

Trap (Trampa): see interceptor (interceptor).

Pipe (Tubería): conduit of regular geometric section (generally circular) intended for the flow of a fluid.

Discharge pipe (Tubería de impulsión): the pipe between the discharge of a pumping equipment and the entrance to an elevated tank or consumption point.

Distribution pipe (Tubería de distribución): pipe intended to carry water to all sanitary fixtures of a building.

Return pipe: pipe that conducts water back to the production system, in a recirculation circuit.

Suction pipe: the pipe between a collection tank and the inlet to pumping equipment.

Vent pipe: pipe with an outlet to the atmosphere intended to allow the entry of air into the drainage systems and the exit of gases from those systems, with the objective of preventing the rupture of the water seal of sanitary traps and maintaining free-flow discharge in the drains.

Auxiliary vent pipe: vertical pipe that connects a drainage branch to the vent pipe of the corresponding circuit, or pipe that connects the main vent pipe to the stack.

Circuit vent pipe: secondary vent pipe connected to a drainage branch and serving a group of fixtures without individual venting.

Individual vent pipe: secondary vent pipe connected to the trap of the discharge pipe of a sanitary fixture.

Main vent pipe: vertical vent pipe to which the individual vents are connected and which ends in a vent extension above the building roof.

Secondary vent pipe: vent pipe that has its upper end connected to a rising pipe or another vent pipe, whether main or secondary.

Horizontal pipe: for the purposes of these standards, any pipe or connection fitting installed in a position that forms an angle of less than 45° with the horizontal.

Vertical pipe: for the purposes of these standards, any pipe or connection fitting installed in a position that forms an angle of 45° or less with the vertical.

- U - Fixture units: empirical unit of flow chosen such that the water demand of sanitary fixtures can be expressed as a multiple of this base unit; the fixture unit of a fixture depends on the type of fixture, the duration of flow, the interval between uses, and the probability of simultaneous use; its definition varies according to the different methods used in calculating potable water supply flows.

Discharge units: empirical unit of flow similar to the preceding one, where the discharges of sanitary fixtures can be expressed as multiples of this base unit.

Flexible joint: see flexible joint (junta flexible).

Urinal: place intended for urinating and, especially, one arranged for the public.

- V - Vacuum: any pressure less than the local atmospheric pressure.

Check valve: valve that prevents flow circulation in a direction contrary to the established one, generally known as a non-return valve (válvula antirretorno), backflow valve (válvula de contraflujo), or check valve (válvula "check").

Safety valve: device intended to prevent pressure elevation above a determined limit, consistent with the normal operating pressure; usually found in hot water, steam, and LP gas systems.

Vacuum breaker valve: vacuum breaker (interruptor de vacío).

Pressure reducing valve: hydraulically operated control valve that reduces high upstream pressure to a lower and constant downstream pressure, unaffected by fluctuations in demand or upstream pressure.

Artificial or mechanical ventilation: the introduction of fresh, uncontaminated air into a given environment of a building, or the removal of vitiated air from it, allowing the entry of fresh, uncontaminated air; for this purpose, it uses mechanical means, such as supply or exhaust fans or ventilation ducts.

Wet venting: the method of venting traps of sanitary fixtures using the drain pipe of a sanitary fixture whose trap is individually vented and installed not less than 40 cm above floor level.

3. GENERAL STANDARDS

Every building intended for human use or occupancy must be provided with a potable water supply system. This system must not affect at any time the degree of purity of the water intended for human consumption and must guarantee its supply (sufficient flow and pressure at all consumption points for its proper functioning), as established in this Code.

Every building intended for human occupancy or habitation, located within an area served by a public water supply in conditions to provide service, must utilize said supply.

When the public supply is not in conditions to provide adequate service, whether due to quality, quantity, or continuity, alternate supply systems shall be permitted, provided that the water source and its purification (potabilización) comply with the requirements established in this Code, as well as the requirements established by the corresponding sanitary and administrative authorities. Attention must be paid to the quantity of minerals present in the water supplied by the alternate system, since demineralized water or water with low mineral content is corrosive, as well as harmful to human and animal health.

Buildings may have a non-potable water supply or a water reuse system for purposes other than human consumption, in a way that contributes to the reduction of potable water consumption and the adequate management of this natural resource. Among the considerations for this type of system are: a) said supply must have separate networks, without any connection to the potable water system, b) that all users of the building are warned, by means of clearly marked and widely distributed notices, about the non-potability of said system, and c) that the pipes are distinguished using the respective colors in accordance with Article 3-9.

Every potable water supply and distribution system shall be protected against cross-connections.

Every building intended for human occupancy must have an independent system for the evacuation of wastewater (aguas residuales) and an independent system for the adequate conduction and evacuation of rainwater (aguas pluviales), in accordance with the provisions of this Code, whether these are individual systems (collection and treatment) or systems managed by public entities, as appropriate. There shall be no cross-connections between the wastewater and rainwater evacuation systems.

Sanitary installations for wastewater drainage (desagüe de aguas residuales) must be designed and constructed in such a way that they allow for rapid flow of waste, prevent obstructions, impede the passage of gases, odors, and animals from the public network into the interior of buildings, do not permit the escape of liquids or the formation of deposits inside the pipes, and prevent contamination of drinking water. No drain shall have any connection whatsoever with the potable water system, nor with the storm drainage system.

Sanitary vent pipes (tuberías de ventilación sanitaria) must allow for adequate evacuation of gases that are produced in or enter the system and guarantee flow conditions at atmospheric pressure, to prevent the loss of hydraulic seals and impede the formation of gas pockets within the drain pipes.

The various piping systems of buildings must be identified in accordance with the official standard for the use of safety colors and its established symbology.

For cases not contemplated in this standard, the Inteco 31-07-03 standard: Color code for the identification of fluids conveyed in pipes may be used as a reference.

Industrial wastewater, hot condensates, corrosive substances, and materials that may cause damage or interfere with existing or planned treatment processes shall not be discharged directly or indirectly into the sanitary sewer system (alcantarillado sanitario), unless they are previously subjected to satisfactory treatment in accordance with the guidelines and standards of the corresponding sanitary and administrative authority, which are:

. Regulation for the discharge and reuse of wastewater (Reglamento de vertido y reuso de aguas residuales).

It is not permitted to pour or discharge rainwater, surface water, groundwater (aguas freáticas), or drainage water into the wastewater sewer system. The wastewater and rainwater systems of buildings shall be totally and completely independent.

Every building located within an area served by a sanitary sewer system (alcantarillado sanitario) in conditions to provide service must discharge its wastewater into said sewer system, except in cases covered by Articles 3-14 and 3-15. The interconnection of the house connection with the sanitary sewer system shall be carried out under the authorization and supervision of the administrative authority of the sewer service.

When there is no sanitary sewer system with the capacity to serve the building, the treatment and disposal of wastewater by means of individual systems shall be permitted, provided they comply with the standards established by the corresponding sanitary authorities (Ministry of Health and AyA).

When the conduction or discharge of wastewater or rainwater cannot be done by gravity, pumping must be carried out in accordance with the provisions of this Code. In the case of single-family domestic installations, the disposal of wastewater by means of domestic treatment systems shall be permitted.

In towns, suburban and rural areas, as well as workplaces where there is no sanitary sewer network nor possibility of excreta disposal by water carriage, these must be deposited in units for dry treatment, wet treatment, composting, or another satisfactory form, provided that the minimum requirements established in this Code and by the sanitary authority are met.

The hydraulic, sanitary, and LP gas installations must be designed and executed taking into account the structural aspect of the building, avoiding any damage or reduction of the resistance of walls, columns, beams, foundations, and any other structural element, as indicated by the Costa Rican Seismic Code (Código Sísmico de Costa Rica).

The materials used in the installations of building drainage systems must comply with the requirements and specifications included in this Code.

The sanitary, hydraulic, and LP gas installations covered by this Code must be planned and designed by professionals registered with the Federated College of Engineers and Architects of Costa Rica (Colegio Federado de Ingenieros y de Arquitectos de Costa Rica), who must follow the provisions of this Code.

The responsible professionals for the sanitary, hydraulic, and LP gas installations of buildings are obligated to comply with the provisions of this Code and will be responsible for the consequences of poor execution of the installations, use of inappropriate materials, and for any alteration made to the work plans.

In the case of condominium buildings, the provisions of Law No. 7933, Regulatory Law for Condominium Property (Ley Reguladora de la Propiedad en Condominios), and its regulations must be respected.

In the case of constructions where it is notified by the corresponding authority that it is necessary to maintain a level of terrain runoff, runoff must be managed through the installation of a retention or detention system, which must comply with the requirements of this Code and the criteria dictated by the institution responsible for the aqueduct.

The hydraulic, sanitary, and LP gas installations must be designed and executed taking into account human safety and fire protection, avoiding any impact on or reduction of the protection of fire and smoke barriers in walls, columns, beams, ceilings, mezzanines, and any other passive protection element, as indicated by the Regulation on Human Safety and Fire Protection (Reglamento sobre seguridad humana y protección contra incendios).

4. POTABLE WATER ALLOWANCES

The minimum water allowances for domestic, commercial, industrial, garden irrigation and other uses shall be calculated according to the provisions of Table 4.1.

Notes:

(1) Does not include allowance for kitchen, laundry, or restaurant.

(2) The allowance refers to liters/day per bed, according to measurements taken in two national hospitals (Hospital México and National Children's Hospital). The allowance should be increased if the hospital has a laundry.

(3) In no case shall the allowance be less than 2000 liters per day (2000 L/day).

(4) Allowance in liters per square meter of usable area.

(5) Allowance in liters per square meter.

(6) Allowance in liters per kilogram of laundry to be washed.

(7) Allowance in liters per day per washing equipment.

(8) Allowance in liters per day per 100 birds.

5. SANITARY FIXTURES 5.1 REQUIRED NUMBER OF SANITARY FIXTURES

The number and type of sanitary fixtures (piezas sanitarias) to be installed in bathrooms, cleaning rooms, lactation rooms, kitchens, and other dependencies of a building or premises shall be proportional to the number of persons served and according to the intended use, in accordance with the requirements of this Code. The indications made by the Construction Regulations (Reglamento de Construcciones) in this regard may also be used, always ensuring the use of the greater number of fixtures.

When a change in the intended use of a premises is made, the necessary modifications must be carried out to comply with the requirements of this Code.

In all types of buildings, whether public or private, where there is public concurrence or service to the public, sanitary facilities (servicios sanitarios) with access facilities for use by elderly persons or persons with disabilities must be provided. These special bathrooms must comply with the requirements given by the Regulation of Law No. 7600, On Equality of Opportunities for Persons with Disabilities (Ley n.º 7600, Sobre la Igualdad de Oportunidades para Personas con Discapacidad) and with the Construction Regulations (Reglamento de Construcciones).

In all types of buildings, whether public or private, where thirty (30) or more women work, there must be at least one lactation room (sala de lactancia materna) so that mothers, in a discretionary manner, can breastfeed, express their milk, and leave it stored. This room shall be an exclusive space for said purpose and must have a minimum area of 3m×3m, with adequate ventilation and lighting, preferably natural, as well as appropriate hygienic, safety, and privacy conditions. At a minimum, the room must have a washbasin (lavatorio) for handwashing. The total number of rooms per building and their dimensions must be in a reasoned proportion to the total number of lactating women expected to work in the building, based on the experience that not all mothers will use them simultaneously.

In all types of buildings, whether public or private, where there is public concurrence or service to the public and with child or family attendance, diaper-changing tables must be provided in men's and women's bathrooms, or bathrooms intended solely for their use and care must be adapted. If the building has only one unisex bathroom, it must have a diaper-changing table.

Alternatively, and safeguarding the privacy and safety of minors, diaper-changing tables may be provided outside the bathrooms, in which case they must be equipped with at least one washbasin (lavatorio) for handwashing, as well as an adequate area for the disposal of solid waste. The diaper-changing tables must have a minimum clear space below the equipment of 760×1220 mm (30×48 inches) and be installed at a maximum height of 865 mm (34 inches) when the table is open. Their installation near a handwash sink and a solid waste container is recommended, as well as being located in common areas of the bathroom, outside of circulation routes. The placement of diaper-changing tables inside any toilet stall must be avoided, so as not to unnecessarily tie the equipment to the stall. Placing them in a family bathroom is also a good option.

In all types of buildings, whether public or private, where there is public concurrence or service to the public and with child or family attendance, child protective seats must be provided in toilet stalls; these seats provide a safe and comfortable place for infants, generally with a maximum weight of up to 22.5 kg (50 lb). These seats shall be installed inside the toilet stall, to provide visual and physical access. They shall be installed at a height from the floor to the bottom of the seat in operating mode of no less than 380 mm (15 inches).

In its installation, the operability and reach of the equipment must be evaluated, both in active and inactive mode, and when the equipment is in use, it must be guaranteed that there is sufficient space to maneuver around the seated infant.

5.1.1 SINGLE-FAMILY AND MULTIFAMILY BUILDINGS

Every single-family residence shall be equipped with at least one bathroom (cuarto de baño) with a toilet (inodoro), washbasin (lavatorio), and shower. The kitchen shall have a kitchen sink (fregadero) and, in a separate place, a washtub (batea) or sink (pila) for washing clothes shall be provided.

Exception: the washtub (pila de lavar) may be omitted in multiple single-family buildings of a single bedroom or single environment or studio type, provided that these fixtures are installed in a roofed area of the building, in a proportion of no less than one washtub (batea) for every three single-family buildings.

5.1.2 COMMERCIAL OR OFFICE BUILDINGS

Buildings intended for commercial premises or offices must be equipped, at a minimum, with sanitary facilities (servicios sanitarios) in the following form, type, and number:

a. In premises with an area up to one hundred fifty square meters (150 m2), or where the number of employees and customers is estimated to be less than fifteen (15), at least one unisex bathroom (cuarto de baño unisex) equipped with a toilet (inodoro) and washbasin (lavatorio) shall be provided for the requirements of employees and customers, whether male or female.

b. In premises with an area greater than one hundred fifty square meters (150 m2), separate sanitary facilities (servicios sanitarios) for men and women shall be provided, each equipped with the sanitary fixtures (piezas sanitarias) indicated in Table 5.1. When using this table, the most critical situation must be used, whether established by the number of persons or imposed by the area of the premises.

c. When it is planned to use sanitary facilities (servicios sanitarios) common to several premises, compliance with point b of this article shall be required. In addition, in a multi-story building, at least one bathroom for men and another for women shall be provided on each floor.

Note: the area of the premises is estimated from the number of persons, considering one person per 10 m2 and that the population is equally divided between men and women.

d. In commercial premises with a large influx of public, such as shopping centers, supermarkets, department stores, bank branches, attraction or amusement parks, museums, and convention centers, among others, there shall be sanitary facilities (servicios sanitarios) for public use for both men and women, at least one on each floor and accessible to persons with disabilities, and in accordance with Table 5.2. In this case, what is indicated in Table 5.1 shall be valid for the permanent staff of the premises.

When using this table, the most critical situation must be used, whether established by the number of persons or imposed by the area of the premises.

e. In commercial premises with a large influx of public, such as shopping centers, supermarkets, department stores, bank branches, attraction or amusement parks, museums, and convention centers, among others, there must be at least one lactation room (sala de lactancia materna) for public and discretionary use so that mothers can breastfeed or express their milk. This room shall be an exclusive space for said purpose and must have a minimum area of 3m×3m, with adequate ventilation and lighting, preferably natural, as well as appropriate hygienic conditions, privacy, and safety. At a minimum, the room must have a washbasin (lavatorio) for handwashing. The total number of rooms per building and their dimensions must be in a reasoned proportion to the total number of lactating women expected in the building, based on the experience that not all mothers will use them simultaneously.

f. Drinking fountains (fuentes para beber) may be installed on each floor occupied by persons and at least one for every eighty (80) persons, which must be accessible to persons with disabilities. These fountains must be disinfected daily to reduce the possibility of bacterial contamination, as well as inspected and maintained regularly.

g. In every building intended for commercial premises or offices, whether public or private, there must be at least one accessible sanitary facility (servicio sanitario) on each floor for the use of men and another for the use of women and, if these are single facilities, they must be accessible to persons with disabilities.

h. A utility sink (pileta) for cleaning the equipment used in cleaning tasks must be installed on each floor.

5.1.3 INDUSTRIAL ESTABLISHMENTS

In industrial establishments, if the staff exceeds ten persons, there shall be separate sanitary facilities (servicios sanitarios) for men and women, equipped with sanitary fixtures (piezas sanitarias) in accordance with the following:

a. Toilets (inodoros) shall be in the proportion of one for every twenty (20) men or fraction of this figure, and one for every fifteen (15) women or fraction of this figure present per work shift, when the total number of workers is less than one hundred (100). When the total number of workers exceeds this amount, one additional toilet (inodoro) must be installed for every twenty-five (25) men and one for every twenty (20) women or fraction of this figure present per work shift.

b. Urinals (mingitorios) shall be in the proportion of one for every thirty (30) men or fraction of this figure working per shift.

c. Washbasins (lavatorios) shall be in the proportion of one for every ten (10) persons or fraction of this figure working per shift, when the total number of persons is less than one hundred. When the number of persons is greater than one hundred (100), one additional washbasin (lavatorio) must be installed for every fifteen (15) workers.

d. In those jobs that, due to their special nature, are hazardous, whether because workers are exposed to excessive heat or skin contamination with poisonous, infectious, or irritating substances or dusts, showers shall be provided in the proportion of one for every ten (10) workers, or fraction of this figure, who cease their work simultaneously.

e. In every industrial establishment, whether public or private, there must be at least one accessible sanitary facility (servicio sanitario) for the use of men and another for the use of women and, if these are single facilities, they must be accessible to persons with disabilities.

f. A utility sink (pileta) for cleaning the equipment used in cleaning tasks must be installed on each floor.

If the staff is composed of ten (10) persons or less, a sanitary room equipped with one urinal (mingitorio), one toilet (inodoro), and one washbasin (lavatorio) shall be provided. This sanitary room must be accessible to persons with disabilities.

In the event that the number of workers is not specified, it shall be estimated based on the proportion of one worker of each sex for every thirty square meters (30 m2) of usable floor area of the building or premises intended for industry.

5.1.4 RESTAURANTS, DANCE HALLS, CAFETERIAS, BARS AND SIMILAR

In premises for restaurants, dance halls, cafeterias, bars, and similar establishments with a service capacity of up to ten (10) persons simultaneously, they shall have at least one bathroom (cuarto de baño) equipped with a toilet (inodoro) and a washbasin (lavatorio); this bathroom must be accessible to persons with disabilities. When the capacity exceeds ten (10) persons, separate facilities for men and women shall be provided in accordance with Table 5.3. At least two (2) of these facilities shall be accessible to persons with disabilities, one for men and one for women. When a change of use is made to a premises, the necessary modifications must be carried out to meet the requirements for the new use.

For service staff, independent sanitary facilities (servicios sanitarios) shall be provided, separate from those of the public, when the number of employees present exceeds six (6) persons. In such case, sanitary facilities (servicios sanitarios) shall be provided in accordance with Table 5.1. When using this table, the most critical situation must be used, whether established by the number of persons or imposed by the area of the premises. At least one of these sanitary facilities shall be accessible to persons with disabilities.

In food preparation areas, the appropriate number of fixtures must be installed, as indicated by the sanitary authority (Ministry of Health).

In the kitchen, facilities for employee handwashing must be provided.

5.1.5 AUDIENCE HALLS, AUDITORIUMS, STADIUMS, TEMPLES AND SIMILAR

In audience halls, such as cinemas, theaters, auditoriums, and similar, as well as in sports buildings, such as stadiums, arenas, hippodromes, bullrings, and similar, bathrooms (cuartos de baños) for the public, separated for men and women, shall be provided as indicated in Table 5.4. At a minimum, there must be two (2) accessible bathrooms (cuartos de baño accesibles), one for men and one for women, exclusively for persons with disabilities.

Drinking fountains (fuentes para beber) shall be installed in the vestibules of each bathroom, never inside the bathroom, according to the following proportions:

a. One fountain: 1-100 persons b. Two fountains: 101-300 persons c. Three fountains: 301-500 persons d. Greater than 500: add one for every 400 persons At least one of these fountains shall be accessible for persons with disabilities. These fountains must be disinfected daily to reduce the possibility of bacterial contamination, as well as inspected and maintained regularly.

In addition, sanitary facilities (servicios sanitarios) must be provided for actors, players, and employees, according to Article 5.9.1.1 and Table 5.1 (using the number of persons and not the area).

TABLE 5.4 NUMBER OF SANITARY FIXTURES IN AUDIENCE HALLS

In religious temples, sanitary facilities (servicios sanitarios) separated by sex shall be provided, and the quantity of fixtures shall be in accordance with the following proportions:

a. Toilet (Inodoro): 1 per 150 men / 75 women.

b. Washbasin (Lavatorio): 1 per 300 men / 150 women.

c. Urinal (Mingitorio): 1 per 75 men.

At a minimum, there must be two bathrooms (cuartos de baño) accessible for persons with disabilities, one for men and one for women.

Religious temples must have at least one lactation room (sala de lactancia materna) so that mothers, in a discretionary manner, can breastfeed or express their milk. This shall be an exclusive space for said purpose and must have a minimum area of 3m×3m, with adequate ventilation and lighting, as well as appropriate hygienic, privacy, and safety conditions. At a minimum, the room must have a washbasin (lavatorio) for handwashing. The total number of rooms and their dimensions must be in a reasoned proportion to the total number of lactating women expected in the temple, based on the experience that not all mothers will use them simultaneously.

5.1.6 PARKING LOTS AND SERVICE STATIONS

In the case of public parking lots, independent sanitary facilities (servicios sanitarios) for men and women shall be provided at a rate of one urinal (mingitorio), one toilet (inodoro), and one washbasin (lavatorio) for men, and two toilets (inodoros) and one washbasin (lavatorio) for women. Each of these sanitary facilities must be accessible to persons with disabilities.

In service stations, at least three sanitary facilities (servicios sanitarios) must be provided. One of them shall be for the workers and two for public use, one for women and one for men. These facilities shall have, at a minimum, one toilet (inodoro) and one washbasin (lavatorio) each, and one urinal (mingitorio) in the men's facility. In addition, an accessible shower must be provided for the workers.

The sanitary facilities (servicios sanitarios) of service stations must comply with the provisions established by MINAE in the Regulation for the Regulation of the Hydrocarbon Storage and Commercialization System (Reglamento para la Regulación del Sistema de Almacenamiento y Comercialización de Hidrocarburos), according to Decree 30131-MINAE.

5.1.7 EDUCATIONAL CENTERS

In educational centers, separate sanitary facilities (servicios sanitarios) for men and women shall be provided for students; the quantity of fixtures to be installed shall be in accordance with Table 5.5.

TABLE 5.5 NUMBER OF SANITARY FIXTURES IN CENTERS At a minimum, there shall be two bathrooms accessible to persons with disabilities on each floor, one for men and one for women.

Bathrooms shall be provided for teachers, professors, and other administrative employees. When the number of these employees is fewer than ten (10) persons, there shall be at least one sanitary service equipped with a lavatory and a water closet. This sanitary service must be accessible to persons with disabilities. When the teaching staff exceeds ten (10) persons, the provisions of table 5.6 shall apply. At least two of these services shall be accessible to persons with disabilities, one for men and one for women.

TABLE 5.6 NUMBER OF SANITARY FIXTURES IN EDUCATIONAL CENTERS FOR TEACHERS

In student residences and similar facilities, the following ratios shall be used: for men, one water closet for every ten (10) men, one lavatory and one shower for every eight (8) men, and one urinal for every fifteen (15); for women, one water closet and one shower for every eight (8) women, one lavatory for every ten (10) women. For men, at least one water closet, one lavatory, one shower, and one urinal must be accessible to persons with disabilities. For women, at least one water closet, one lavatory, and one shower must be accessible to persons with disabilities.

Higher education teaching centers must have at least one lactation room (sala de lactancia materna) so that students who are mothers may, at their discretion, breastfeed, extract their milk, and leave it stored. This shall be an exclusive space for said purpose and must have a minimum area of 3m×3m, with adequate ventilation and lighting, as well as appropriate hygienic, privacy, and safety conditions. At a minimum, the room must have a lavatory for handwashing.

The total number of rooms and their dimensions must be in reasonable proportion to the estimated total number of female students who are lactating at the teaching center, based on the experience that not all mothers will use it simultaneously, but must also be in reasonable proportion to the number of buildings that make up the teaching center.

Service sinks (pilas) must be provided on each floor of the institution for cleaning equipment upkeep.

Preschool centers and schools. The sanitary fixtures shall be of a design and dimensions suitable for use by schoolchildren and shall be installed at an appropriate height. The quantity of sanitary accessories may be selected from table 5.7.

In preschool centers and schools, handwashing sinks (lavamanos) must be installed so that their top edge is not at a height greater than sixty-five centimeters (65 cm) from the finished floor level.

TABLE 5.7 NUMBER OF SANITARY FIXTURES IN PRESCHOOL CENTERS

When exclusive bathrooms for each dormitory are not available, the establishment must comply with the following:

a. One lavatory with cold water and a drain in each dormitory.

b. One bathroom and one lavatory for every three dormitories or for every five beds; they must be accessible to persons with disabilities.

c. One accessible and independent water closet for every three dormitories or for every five beds and, in any case, at least one on each floor.

d. The sanitary services must not be located more than forty meters (40.0 m) from the most horizontally distant room.

e. One accessible drinking fountain (fuente de beber) for every seventy-five (75) guests, at least one on each floor, installed in the lobby; they must be disinfected daily to reduce the possibility of bacterial contamination, as well as be regularly inspected and maintained.

f. All hotels or similar establishments must have one service sink (pileta de servicio) for every twenty dormitories, with at least one on each floor.

The sanitary services intended for the public visiting the establishment and those for staff must be independent. The number of sanitary fixtures shall be estimated based on table 5.2. At a minimum, there must be two accessible bathrooms intended for the public, one for men and one for women.

5.1.9 SPORTS FACILITIES AND PUBLIC BATHS

Sanitary services for men and women shall be provided in accordance with the following:

a. Men: one water closet for every twenty (20) men, one lavatory for every fifteen (15) men; one shower for every five (5) men, and one urinal for every twenty-five (25) men. At least one sanitary fixture of each type must be accessible to persons with disabilities.

b. Women: one water closet and one lavatory for every fifteen (15) women, and one shower for every five (5) women. At least one sanitary fixture of each type must be accessible to persons with disabilities.

Swimming pools. For estimating the number of bathers in swimming pools, one person shall be considered for each one and a half square meters (1.5 m2) of the pool's liquid surface.

At the access to each swimming pool, at least one accessible shower must be located for bathers to wash before entering it.

Drinking fountains (fuentes para beber). They may be installed outside the sanitary services, in a proportion of one for every two hundred (200) persons. This fountain must be accessible to persons with disabilities. Drinking fountains must be disinfected daily to reduce the possibility of bacterial contamination, as well as be regularly inspected and maintained.

5.1.10 WORKS UNDER CONSTRUCTION

Every work under construction must have an adequate excreta disposal system, with capacity proportional to the number of workers on the site, and must have a potable water service for their personal hygiene (aseo).

Provisional water closets or latrines shall be installed, at a rate of one for every eight (8) workers.

5.1.11 HOSPITALS, CLINICS, AND CARE CENTERS

Buildings intended for health facilities, indicated below, shall be equipped with sanitary services and sanitary fixtures of the type and minimum number noted in each case. At a minimum, there shall be two bathrooms accessible to persons with disabilities on each floor, one for men and one for women.

5.1.11.1 CENTERS WITH HOSPITALIZATION

In health centers where private-use sanitary services are provided for each room, one water closet, one shower, and one handwashing sink shall be installed.

In centers where rooms do not have a bathroom, or in general hospitalization wards and for the use of hospitalized patients, the following shall be provided:

a. Separate sanitary services for men and women, on each floor intended for hospitalization.

b. In each of the required sanitary services, at least one water closet, one lavatory, one urinal, and one shower shall be installed for every ten (10) patients, in addition to one cleaning sink (pila de aseo) for every ten (10) patients.

In sanitary services for men, water closets may be substituted with urinals, but in such proportion that the number of urinals is not greater than one third of the total number of required water closets.

For the use of visitors and their companions, at least one bathroom for men and one for women shall be provided in the waiting rooms. In each of these, at least one water closet and one handwashing sink shall be installed. In addition, one drinking fountain shall be installed on each level, located outside the sanitary services, which must be accessible to persons with disabilities. This fountain must be disinfected daily to reduce the possibility of bacterial contamination, as well as be regularly inspected and maintained.

The type and minimum number of sanitary fixtures to be installed in rooms adjacent to operating rooms, maternity wards, morgues, and other services of the medical center shall correspond to the specific standards dictated in this regard by the competent sanitary authority (autoridad sanitaria competente).

For the use of resident staff, employees, and workers of the healthcare center, additional, adequately located sanitary services shall be provided, both for men and for women, and in them, sanitary fixtures of the type and minimum number indicated in table 5.1 shall be installed. When using this table, the most critical situation must be used, whether that established by the number of persons or that imposed by the area of the premises. At a minimum, there shall be two bathrooms accessible to persons with disabilities on each floor, one for men and one for women.

Each floor must have one cleaning sink (pileta de aseo), at least one per floor.

5.1.11.2 OUTPATIENT CONSULTATION CENTERS

In each consulting room (consultorio), a bathroom with a handwashing sink and a water closet shall be installed, when required.

In the waiting rooms of the consulting rooms and for the use of the patients' companions, one accessible bathroom for men and one for women shall be installed, and in each one, at least one handwashing sink and one water closet shall be installed.

For the use of resident staff, employees, and workers of the healthcare center, additional, adequately located sanitary services shall be provided, both for men and for women, and in them, sanitary fixtures of the type and minimum number indicated in table 5.1 shall be installed. When using this table, the most critical situation must be used, whether that established by the number of persons or that imposed by the area of the premises. At a minimum, there must be two (2) bathrooms accessible to persons with disabilities on each floor, one for men and one for women.

5.1.11.3 DENTAL CLINICS AND OFFICES

Each single dental office (consultorio dental único) must provide one bathroom, accessible to persons with disabilities, for the use of patients and their companions, in which at least one handwashing sink and one water closet shall be installed.

In each dental office, at least one handwashing sink directly accessible from the dental unit shall be installed.

Dental clinics where several dental offices operate simultaneously may be equipped with sanitary services common to them, separated for men and for women. In each of them, at least one water closet and one handwashing sink shall be installed. At a minimum, there shall be two bathrooms accessible to persons with disabilities on each floor, one for men and one for women.

5.1.12 JAILS AND CORRECTIONAL CENTERS

In the event of individual cells, one water closet and one handwashing sink shall be installed in each cell.

In the event of common cells, the minimum quantity of accessories to be installed in the sanitary services must comply with the following:

. One water closet for every twenty (20) men.

. One urinal for every fifty (50) men.

. One water closet for every fifteen (15) women.

. One handwashing sink shall be installed for every ten (10) persons deprived of liberty (privados de libertad).

. One shower shall be installed for every fifty (50) persons deprived of liberty.

. One drinking fountain shall be installed on each floor, located outside the sanitary services; these fountains must be disinfected daily to reduce the possibility of bacterial contamination, as well as be regularly inspected and maintained.

. One service sink (pila de servicio) shall be installed on each floor.

For the use of resident staff, employees, and workers, additional separate sanitary services for men and for women shall be provided, in accordance with the provisions of table 5.1. When using this table, the most critical situation must be used, whether that established by the number of persons or that imposed by the area of the premises.

5.2 SPECIFICATIONS FOR SANITARY FIXTURES 5.2.1 GENERAL STANDARDS

Sanitary fixtures must be constructed of hard, resistant, and impermeable materials, such as porcelain, vitrified stoneware, stainless steel, or any other with characteristics similar to those mentioned. The surfaces of the fixtures must be smooth and free of interior or exterior defects.

Low-consumption accessories. In order to include practices on the rational use of natural resources, the use of accessories that handle lower flows than traditional accessories is recommended. The accessories may be identified by possessing an efficiency seal given by some global organization, for example the USEPA (United States Environmental Protection Agency).

Cross-connection. Sanitary fixtures must be installed in such a way that they do not present cross-connections that could contaminate the potable water.

To prevent cross-connections, the free space between the supply faucet outlet and the overflow level in the sanitary fixtures must be in accordance with table 5.8.

TABLE 5.8 MINIMUM FREE SPACE TO PREVENT A CROSS-CONNECTION 5.2.1.1 INSTALLATION

In sanitary fixtures that have hot and cold water supply, the cold water must be delivered on the right and the hot water on the left, facing the fixture.

In the case of a single control faucet, the direction of rotation shall be applied according to whether it is cold or hot.

Sanitary fixtures must be installed in adequate environments, providing for the minimum spaces necessary for their proper use, cleaning, repair, inspection, and ventilation, as specified in section 5.3.

Accessories connected by a union joint (unión de tope) must have an access panel or a useful space of at least thirty centimeters (0.30 m) in its smallest dimension. Where practical, all pipes coming from the accessories must be close to the walls.

Every sanitary fixture must be equipped with its corresponding trap (sifón) for the water seal. The water seal must have a height of at least five centimeters (0.05 m) minimum.

Water closets, bidets (bidés), and similar sanitary fixtures placed on the floor must be fixed with screws, bolts, or by some other system that allows their disassembly. They shall be installed on an appropriate accessory (for example: flange and ring or wax seal).

Fixture Free Space (mm) Wall-mounted sanitary fixtures shall be fixed by means of metallic supports in such a way that no stress is transmitted to the pipes and connections.

The bolts or screws must be made of copper, brass, or other corrosion-resistant material.

Backflow. Supply pipes or sanitary accessories must be installed to prevent any backflow (reflujo).

Every sanitary fixture built on-site must be covered with an impermeable vitrified material and with all interior and exterior edges rounded.

Prohibited accessories. The installation of dry or chemical type water closets shall not be permitted in buildings for human use.

5.2.2 WATER CLOSETS

Water closets with a tank must comply with the following requirements:

a. In the water inlet pipe to the tank, there shall be a shutoff valve (válvula de paso).

b. The tanks shall have sufficient capacity to ensure complete cleaning of the fixture.

c. The flush mechanism shall function in such a way that it avoids water loss or waste, replenishes the water seal of the fixture, and prevents cross-connections.

d. Water closets with a tank must have the capacity to discharge, if any overflow occurs, into the tank itself.

Water closets with a semi-automatic valve must comply with the following requirements:

a. Each water closet shall be equipped with its corresponding shutoff valve installed near it, in a place easily accessible for repair.

b. The semi-automatic valve must allow the passage of water at sufficient flow and pressure, in accordance with the manufacturer's recommendations, to discharge and wash the water closet, and to replenish the water seal in each operation.

c. They may only be installed when it is ensured that the minimum required pressure and flow will be maintained in the supply system.

d. The semi-automatic flush valve shall be adjustable, so that the flush volume and working pressure can be regulated.

e. The branch supply pipe for several water closets with a semi-automatic flush valve shall be equipped with a shock absorber to absorb the effects of water hammer (golpe de ariete).

The seats and covers of water closets shall be of impermeable, smooth, and easy-to-clean material. Water closets for public use shall be of the elongated type and the seat shall have an open front.

In institutions such as kindergartens, preschools, and other similar places where sanitary fixtures will serve persons under seven years of age, the sanitary fixtures must have an adequate height for such persons. For water closets, the heights indicated in table 5.9 are recommended.

TABLE 5.9 DIMENSIONS FOR WATER CLOSETS OPERATED BY PERSONS UNDER 7 YEARS OF AGE

To achieve proper functioning of water closets, the following recommendations must be followed:

a. Water closets must have a vent pipe, which aids in the free discharge of waste. This pipe must be at least thirty-eight millimeters (0.038 m) in diameter.

b. The vent pipe must be located at a distance of at least thirty-three centimeters (0.33 m) from the water closet outlet. In case it cannot be located close to the water closet, it may be located at a distance of no more than three meters (3.0 m) from the water closet outlet.

c. In the case of floor-discharge water closets, the height between the water closet outlet and the discharge pipe must be such that it avoids turbulence during the flush and, furthermore, allows the development of an adequate discharge velocity, which must not be very high, as it can cause siphoning (sifonaje). The distance between the center of the sanitary elbow (codo sanitario) and the finished floor level must be in the range of twenty-five to sixty centimeters (0.25 - 0.60 m).

d. The slope of the discharge pipe must be 1.5%, allowing a maximum variation of ±0.5%, in order to achieve correct carrying of solids.

e. The materials necessary for correct assembly of the water closet are: the plastic flange, the anchor bolts, and the wax gasket. The use of cement to fix the bowl to the floor is not recommended.

f. A space of at least one centimeter (0.01 m) must be left between the water closet tank and the wall, so the correct location of the drain pipe with respect to the finished wall level is important, according to the distances indicated by the manufacturers.

5.2.3 URINALS

Urinals (mingitorios or urinarios) must comply with the following requirements:

a. Be provided with an adequate system that allows washing of the sanitary fixture, which may be an automatic flush tank for one or more urinals, individual semi-automatic valves, or another system.

b. Urinals provided with semi-automatic valves must comply with the same specifications as for water closets with a flushometer valve.

c. If waterless urinals are used, they must be provided with the appropriate means to prevent the entry of gases into the bathroom where they are located, resulting from the chemical process to which they are subjected. This type of urinal must have the proper trap, whether by seal or by hydraulic operation of the outlet devices, which can be achieved with the application of oils, special gels, and by using diaphragms or devices of latex or other similar materials.

5.2.4 SHOWERS

The spaces intended for showers must comply with the following requirements:

a. They shall be located in such a way that the water falls onto a free area.

b. The floor must be of impermeable and non-slip material when dry and wet, with a minimum slope of two percent (2%) and a maximum of four percent (4%) towards the drain. A small wall or step may be placed to prevent water runoff to other parts of the bathroom. The barrier (dique) or step shall not be less than five centimeters (0.05 m) and not greater than twenty-three centimeters (0.23 m). In the event that a wall or step is not used in order to facilitate accessibility, the floor or the shower tray must be flush with the surrounding floor of the bathroom and the slope of the inclined planes formed to facilitate drainage shall be 2%.

c. The drain shall be equipped with a trap (sifón) and provided with a removable grating (rejilla) made of stainless material. The openings of the grating must be such that they allow the service flow of each shower to be evacuated quickly, without accumulating water.

d. The floors of showers for public use shall have the slope arranged in such a way that the wastewater (agua servida) from each shower does not pass through the areas intended for other bathers.

e. All edges on the floor and wall corners shall be rounded.

f. The walls shall be finished with impermeable material up to a minimum height of one and a half meters (1.5 m).

g. Bathtubs of the built-in or semi-built-in type must have a watertight joint between the wall and the sanitary fixture.

5.2.5 SINKS AND HANDWASHING SINKS

Laundry sinks (pilas para lavar ropa), kitchen sinks (fregaderos), and handwashing sinks (lavamanos) must be provided with adequate devices that prevent solids from passing into the drainage system, and their trap must be easily accessible (registrable) for cleaning.

The minimum capacity and dimensions of the handwashing sink shall be: length of 33 cm, width of 23 cm, depth of 13 cm, and must be in accordance with the proposed use in the judgment of the competent sanitary authority.

5.2.6 FLOOR DRAINS

Floor drains (sumideros) must comply with the following requirements:

a. The corresponding water seal shall have a minimum height of seven and a half centimeters (0.075 m).

b. They shall be provided with removable, perforated, or slotted covers. The free area of the cover shall be at least 66% of the area of the corresponding discharge pipe.

The dimensions of the cover and its discharge pipe shall be such that they ensure the proper functioning of the device.

Floor drains must be installed in the following places:

a. In sanitary services that have two or more water closets, or one urinal and one water closet, except in single-family dwellings (viviendas unifamiliares). The floor must have an inclination towards the floor drain.

b. Commercial kitchens.

c. In laundry rooms of commercial buildings or in common laundry areas in multifamily buildings.

d. In food storage areas, such as storage rooms, accessible cold rooms, and similar; these drains must be indirect; a separate drain shall exit from each area and shall be connected indirectly to the sanitary drain of the building.

In the case of accessories such as ornamental ponds, aquariums, swimming pools, ornamental fountains, commercial water dispensers, and similar constructions, they must be protected against backflow (reflujo), if they are fed directly from the potable water system.

Accessories provided with overflow devices must comply with these requirements:

a. The overflow capacity must be sufficient to discharge the maximum supply flow of the fixture.

b. The overflow device must be such that water does not become stagnant in it.

c. The overflow shall drain between the discharge outlet and the trap of the corresponding sanitary fixture. In the case of the overflow pipes of water closet and urinal tanks, these may discharge into the respective water closet or urinal.

5.2.7 DRINKING FOUNTAINS

Drinking fountains, with or without self-contained cooling, shall be of specific design for the proposed use and must comply with the following requirements:

a. Be provided with means to regulate the discharge pressure.

b. Have a self-closing faucet (llave de cierre automático) with manual or foot operation.

c. The jet outlet orifice must be protected, so as to prevent direct contact with the lips.

d. The jet outlet angle must be inclined between approximately 60 and 45 degrees.

Drinking fountains may not be installed inside bathrooms and must be disinfected daily to reduce the possibility of bacterial contamination, as well as be regularly inspected and maintained.

5.2.8 BIDETS

When it is desired to install a bidet in a private-use bathroom, the following requirements must be met:

a. The valves and other supply connections of the sanitary fixture must allow the passage of water at an adequate flow, to wash the entire interior surface of the fixture, drain the wastewater, and replenish the water seal in each operation.

b. The design of the fixture must guarantee washing of the entire interior surface thereof, after each operation.

c. The bidet may be substituted by a manual-operation shower. The shower shall be installed near the water closet, shall be equipped with shutoff valves and flexible hose, and shall be equipped with holding and fastening parts to prevent it from remaining on the floor, and shall be located no less than 30 centimeters above the overflow level of the water closet.

d. It must have a trap or water seal (trampa de agua).

5.3 SPECIFICATIONS FOR BATHROOMS

All sanitary fixtures and their accessories must be installed maintaining their correct spacing and allowing their access and proper use. Figure 5.1 indicates the suggested minimum dimensions for the installation of sanitary fixtures.

In all sanitary services for public use, floor drains shall be provided to facilitate their adequate sanitation.

The minimum area of bathrooms in single-family and multifamily dwellings (including one lavatory, one water closet, and one shower) shall be two and a half square meters (2.5 m2) in area and one meter (1.0 m) in width.

The provisions of the Construction Regulations (Reglamento de Construcciones) must be complied with, according to the type of building. In the event that the Construction Regulations do not give specific indications for a type of building, the following may be considered:

a. The minimum height of bathrooms from floor to ceiling (cielo raso) shall be two meters forty centimeters (2.40 m), provided that the roof covering or ceiling, if any, is made of insulating or heat-reflective material.

b. If the roof material is not insulating, the height must be increased to a minimum of two meters sixty centimeters (2.60 m). A minimum height of two meters twenty-five centimeters (2.25 m) may be accepted, provided that the ventilation area is increased by 15%.

Bathrooms must have lighting and ventilation by means of windows, skylights (linternillas), or light shafts (tragaluces), which open directly onto patios or public space. Ventilation may also be provided by mechanical means, provided that the standards of the competent sanitary authority are met.

The requirements for bathrooms regarding lighting, natural ventilation, door and window dimensions, and other architectural details must comply with the requirements of the Construction Regulations.

5.3.1 ARTIFICIAL VENTILATION

Sanitary services may be artificially ventilated and must comply with the provisions of this Code.

Every artificial or mechanical ventilation system for a space shall be based on the injection of fresh and uncontaminated air into the interior of the space of a building and shall allow the exit of stale air to the exterior; or, the extraction of stale air from the space shall allow, at the same time, the entry of a quantity of fresh and uncontaminated air from the exterior.

For any ventilation system to be developed, the fresh and uncontaminated air intakes must be made directly from the exterior of the corresponding building.

The velocity of air introduced into enclosures for artificial ventilation purposes must not exceed by more than ten percent (10%) the values noted in table 5.10.

The stale air from any artificial ventilation system must be discharged directly to the exterior of the building and in such a way that it cannot return, nor affect in any way neighboring buildings.

The number of air changes per hour necessary for the artificial ventilation of a bathroom shall be determined according to the type of building and its use, in accordance with what is noted in table 5.11.

Sanitary services in buildings up to three floors in height may be artificially ventilated by extraction, by means of individual fans installed in each bathroom, provided with back-draft dampers (compuertas con contraflujo) and connected to ducts intended exclusively for bathroom ventilation.

The ducts referred to in the previous article must have a sufficient cross-section so that, if all fans are operating, the air velocity in the duct is no greater than five meters per second (5 m/s).

The sanitary services of buildings of any number of floors may be artificially ventilated by extracting air from them using a fan installed at the highest part of a vertical ventilation duct, intended exclusively for that purpose and common to all the sanitary services.

The extraction grilles must be equipped with individual adjustment mechanisms, in order to allow regulation of the amount of air to be extracted from each bathroom.

The access doors of sanitary services artificially ventilated in accordance with the specifications in the previous articles must be provided with an opening or other system that allows the entry of fresh air. The minimum area of this opening shall be estimated using the following equation:

Where, Q: airflow extracted from the bathroom (m3/s) V: velocity of the air entering through the grille.

For commercial premises and offices, this has a range of seventy to one hundred centimeters per second (0.7-1.0 m/s). For industrial buildings, the range is two hundred fifty to four hundred centimeters per second (2.5-4.0 m/s).

6 COLD WATER AND HOT WATER SYSTEMS 6.1 GENERAL STANDARDS

The execution of the residential connection shall be the responsibility of the administrative authority of the potable water service.

The potable water distribution system of buildings must be designed according to the conditions under which the public water supply will provide service.

The basic symbology to be used in sanitary and hydraulic installation plans shall be that indicated in figure 6.1.

a. Direct connections between the public network pipes and pumps or other mechanical pressure-boosting devices shall not be permitted.

b. The potable water distribution system in a building shall not be connected, directly or indirectly, to any non-potable water system.

c. Direct or indirect connections between the public water supply and the private or emergency supply are strictly prohibited.

The water supply and distribution system shall be equipped with valves suitable for the existing pressure, as shown in figures 6.2 and 6.3, and at minimum at the following points:

a. One at each connection to the public service, after the corresponding meter.

b. One on each floor, one for each independent section in apartment or office buildings, or for each floor section that has no horizontal communication.

c. One in each collective or public bathroom, in public or commercial office buildings.

To prevent possible water backflow, it is advisable to place a check valve after the meter. Furthermore, check valves must be placed at the points indicated in figure 6.2.

When the public water supply guarantees continuous service at sufficient pressure and flow, the distribution system may be served directly from the public network, as shown in figure 6.2a.

When the public water supply does not guarantee continuous service, one of the following indirect systems shall be used:

a. Elevated tank (figures 6.2b and 6.3a) b. Collection tank, pumping equipment, and hydropneumatic tank (figures 6.2e and 6.3d) c. Cistern, pumping equipment, and elevated tank (figures 6.2c, 6.3b, 6.3c, 6.3e, and 6.3f)

When the public water supply does not guarantee sufficient pressure, the building's distribution system must use one of the systems stipulated in subsections b and c of the previous article.

In high-rise buildings, the distribution system shall be designed in groups of floors, such that the pressures specified in section 6.3.1 are not exceeded (see figure 6.3).

6.2 MATERIALS FOR PIPES, VALVES, AND FITTINGS

In works for water supply and distribution, only pipes and fittings of the following materials shall be used:

a. PVC b. Galvanized iron c. Copper d. High-density polyethylene e. CPVC f. Polypropylene g. Black iron Indications:

. CPVC pipes may be used for both cold and hot water distribution.

. In copper pipes, the use of type K, L, or M pipe is permitted. Type M pipe may be used for water distribution if the pipe is located on the floor or on the building, or buried in a site without any structure.

. Valves of a size less than or equal to 51 mm (2 in.) must be made of bronze or another approved material. For sizes larger than 51 mm, the valve body must be made of cast iron or bronze.

. The connecting pieces to be used should preferably be of the same material as the pipes they join and of matching characteristics.

. The connection between pipes of different materials between which no galvanic action occurs shall be made directly or using suitable adapter or converter connecting pieces.

. The corresponding joints may be soldered, electrofusion-welded, thermofusion-welded, threaded, press-fit, flanged, or mechanical, or a combination thereof, depending in each case on the types of pipes to be joined and their characteristics.

. The pipe joints must be in accordance with their class; they may be of the following types: spigot and bell, flanged, threaded, welded, and connected, by means of rubber rings, mechanical, and compression.

. When it is desired to use pipes of materials other than those specified in this section, it may be done in accordance with the technical analysis performed by the professional responsible for the design or the professional responsible for the execution of the work. The objections of the health authority or other State institutions that must inspect the project must be taken into account.

Pipes must meet the following general requirements:

a. Homogeneous material b. Circular cross-section of standardized dimensions c. Uniform wall thickness d. Dimensions, weights, and thicknesses in accordance with the specifications corresponding to the respective operating conditions e. Free from defects such as cracks, dents, and deformations

Technical regulations.

For all types of pipes, connections, and fittings, with the exception of those manufactured in PVC and CPVC, while national industrial technical standards are not in force, they shall be considered of satisfactory quality if they meet the most recent specifications of qualified entities, such as the American Society for Testing and Materials (ASTM), the American Water Works Association (AWWA), or the International Organization for Standardization (ISO).

PVC Regulations.

In the case of PVC and CPVC pipes, the pipes and their fittings must comply with the following standards:

ASTM D - 2241 for potable water pipes ASTM D 1785 for potable water pipes ASTM D 2466 fittings for potable water pipes ASTM D 2464 fittings for potable water pipes ASTM D 2846 for CPVC pipes and fittings for hot water (DWG) ASTM D- 3350 for polyethylene (PE) pipes and fittings 6.3 STANDARDS FOR DIMENSIONING DISTRIBUTION PIPES 6.3.1 MINIMUM PRESSURES AND DEMANDS

The minimum pressure at the nodes of the distribution system shall allow adequate operation of the corresponding sanitary fixtures. Table 6.1 indicates the recommended minimum pressures for the operation of various sanitary appliances. In no case shall the pressure at the inlet of the sanitary fixtures be less than two meters of water column (2 mca). If the maximum pressure at the supply points of the sanitary fixtures is greater than forty meters of water column (40 mca), the system must be divided into pressure zones, or pressure-reducing valves must be installed.

The service pressure after the meter must be greater than ten meters of water column (10 mca).

(1) Minimum internal diameter of supply pipe. In the case of toilets and washbasins, this diameter refers to the supply branch up to the shut-off valve.

(2) Minimum pressure at the fixture inlet in meters of water column (or head).

(3) The minimum pressure depends on the type of semi-automatic valve.

(4) Flow rates based on fixture units. These flow rates are for dimensioning both pipes that carry only cold water and those that carry cold water and the flow that must be heated. In the event of fixtures with independent supply for cold water and hot water, it may be assumed that three-quarters of the flow rates described in this table shall circulate through each one.

6.3.2 FLOW VELOCITIES

For the dimensioning of distribution pipes, a minimum velocity of sixty centimeters per second (0.60 m/s) is recommended to prevent sedimentation of particles, and a maximum velocity of two meters per second (2.00 m/s) to prevent excessive noise in the pipes and water hammer.

To avoid excessive head losses, it is recommended to maintain maximum velocities according to the expression:

Where: V is the velocity in meters per second and is the square root of the internal diameter of the pipe in meters and in no case greater than two meters per second (2.0 m/s). The recommended velocities result in friction losses ranging between ten and twenty centimeters of water column (0.10 and 0.20 mca) per linear meter of pipe.

Table 6.2 indicates the recommended maximum velocities and flow rates in accordance with the previous criteria, for galvanized iron, CPVC, and PVC pipes.

Note:

(1) Estimated for SDR 17 pipe (SDR 13.5 at 12 mm).

(2) Galvanized iron.

(3) Head loss per unit length of pipe estimated according to section 6.3.4.a).

6.3.3 DESIGN FLOW RATES

The design flow rate of the distribution pipes shall be calculated according to Hunter's method. This method, based on the calculation of probabilities of simultaneous use and on empirical observations, assigns weights to each type of intermittently operating sanitary appliance. These weights consider, for such fixture, the required flow rate, its duration, and its usual frequency of operation. This is quantified by the so-called water supply fixture units (u.a). Such units have been selected so that the total flow rate of a system or subsystem with different types of fixtures and their service conditions can be approximated as a multiple of that factor.

Table 6.1 indicates the fixture units for different sanitary fixtures, under different service conditions. If the fixture is not included in said table, table 6.3 may be used.

The probable maximum flow rate in a supply branch is a function of the sum of the fixture units of all the appliances served by said branch. The relationship between the total fixture units and the probable maximum flow rate is formally described by the equations in table 6.4, but can be found according to table 6.5 or with the graph in figure 6.4.

When a system does not supply any toilet, the corresponding flow rate is obtained using the equations or values corresponding to a system where toilets with flush tanks predominate.

For the estimation of the flow rate in any water supply pipe in a building, any load from other systems must be added to the fixture flow rate, such as sprinklers of the fire-fighting system (residential case), requirements of the air conditioning system, hot water or steam generators, irrigation systems, among others.

6.3.4 HEAD LOSSES

For the calculation of head losses caused by friction in distribution pipes and supply branches, the use of the Darcy-Weisbach formula is recommended, as it offers the greatest accuracy for calculating head losses in pipes. However, the professional responsible for the design may use other formulations accepted by the good practices of the profession. The Darcy-Weisbach method is expressed as follows:

Where, D= internal diameter of the pipe (m) f= friction factor g= acceleration due to gravity (m/s²) hf= energy loss (m) L= length of the pipe (m) V= velocity of the liquid in the pipe (m/s) For pressurized water systems, the following arrangement of the Darcy equation may be used:

Where, Q= flow rate in the pipe (L/s) D= internal diameter of the pipe (mm) The friction coefficient f is calculated from the Colebrook White formula, or its graphic equivalent, the Moody diagram. The Haaland equation, shown below, is explicit and approximates the Colebrook White equation, with an error of less than 2% in the calculation of the friction factor.

TABLE 6.6 ABSOLUTE ROUGHNESSES FOR THE COLEBROOK WHITE FORMULA

Localized losses or minor losses caused by changes of direction, valves, reductions, flow meters, and other fittings must be considered. Table 6.7 and figure 6.5 contain the local loss coefficients necessary to estimate losses in meters of water column.

6.4 CONSTRUCTION REQUIREMENTS FOR POTABLE WATER INSTALLATIONS 6.4.1 INSTALLATION AND LOCATION

In buildings of three or more stories, cold water and hot water pipes in vertical sections shall be placed in ducts provided for that purpose, whose size must be sufficient for their convenient installation, inspection, repair, and removal.

Between cold water and hot water pipes installed in the same duct, there must be a minimum separation of ten centimeters (0.10 m) from edge to edge, unless they are protected with a suitable insulating material.

The placement in the same vertical duct of wastewater downspouts, rainwater downspouts, and the cold or hot water supply or distribution pipes shall be permitted, provided there is a minimum separation of twenty centimeters (0.20 m) from edge to edge between them.

It is advisable that horizontal water supply pipes (both cold and hot) be installed with a slope towards the corresponding vertical supply pipe. Whenever possible, purge valves shall be placed at the low points of the horizontal pipes on the ground floor. If the building has a basement, purge valves must be placed at the lowest points of the horizontal pipes.

Water hammer. To attenuate the overpressures that water hammer may cause, the installation of air chambers or special fittings for this purpose is recommended.

Air chambers consist of vertical extensions with capped ends of the supply pipe for washbasins, sinks, showers, and bathtubs. These extensions shall have a diameter equal to or greater than that of the supply pipe and their length shall be sixty centimeters (0.60 m). Air chambers can cease to function over time; therefore, their use is not recommended in commercial, industrial, hospital, or public assembly buildings.

6.4.2 SUPPORT OF PIPES AND STRUCTURAL ELEMENTS

For the passage of pipes through structural elements, sleeves or bushings shall be placed. The length of the bushing or sleeve shall be equal to the thickness of the element, and its diameter shall be such that it allows the proper passage of the pipes and insulation, so that there is a clearance between the sleeve and the pipe (or the insulation) of at least twelve millimeters (12 mm).

Horizontal and vertical hanging pipes shall be held by clamps fixed to the ceiling or wall by means of suspension devices made of resistant material. The spacing between supports shall be determined according to the mechanical strength of the pipes, but shall not be greater than the values given in table 6.9. In the selection of the clamp material, the prevention of galvanic corrosion must be considered.

Pipes that cross expansion or dilation joints in buildings must be provided, at the passage points, with flexible connections or expansion joints. Likewise, those that may be subject to vibrations shall be protected by flexible joints at the connection with mechanical equipment.

The dimensions of the clamps and suspension devices must guarantee the structural requirements regarding support, stability, and stresses caused on the pipe, and may be selected according to table 6.8.

Note:

1. Pipe expansion must be allowed every 9.1 m.

6.4.3 BURIED PIPES

When potable water distribution pipes are buried, they must be kept as far away as possible from wastewater drains, and must be separated from these by a minimum distance of one meter (1.0 m) in plan and twenty-five centimeters (0.25 m) above. When water pipes cross drains, they must always be placed above them and at a vertical distance of not less than twenty-five centimeters (0.25 m).

Buried pipes must be placed in excavated trenches of dimensions such that their easy installation is permitted. The minimum depth of the trench shall be such that there is at least thirty centimeters (0.30 m) between the crown of the pipe and the ground level. Before proceeding with the placement of the pipes, the bottom of the trench must be compacted. Once the pipes are placed, and the trench filled and compacted, they shall be inspected and subjected to the tests stipulated in section 6.8. The trench backfill shall be carried out using suitable material, spread in horizontal layers of a maximum of fifteen centimeters (0.15 m) thickness, duly compacted.

If buried metal pipes are used, they must be protected against corrosion with suitable materials. Galvanized iron pipe must not be buried.

The valves for pipes that remain below the ground or floor level must be provided with a protective box. This box must be placed in an accessible location and shall be such that it permits the repair, removal, and operation of the valves.

Buried pipes must be kept away from the foundation of buildings, in order to avoid subjecting it to high compressive stresses. Buried pipes must be located above a 45° projection from the foundation slab.

6.5 STORAGE TANKS

Every building located in sectors where the water supply is not continuous or lacks sufficient pressure must be provided with one or several storage tanks that allow the adequate supply of water to all the sanitary fixtures or planned installations. These tanks may be installed on the lower levels (collection tank), on intermediate floors, or on top of the building (elevated), provided they comply with the stipulations of this chapter and are in accordance with the fundamental characteristics of the models shown in figures 6.6, 6.7, and 6.8.

Water tanks must be designed to guarantee the potability of the water at all times and prevent the entry of rainwater, rodents, or other contaminants.

In the case of condominiums and multi-family buildings, they must have direct access from the common areas of the building for their proper operation, inspection, and maintenance.

The materials for storage tanks must meet the following general requirements: impermeable, odorless, and must not impart taste to the water. These materials may be: plastics, metals, fiber cement, fiberglass, reinforced concrete, or other materials approved by the health authority.

Water from the washing, drainage, or overflow of the tanks must be directed to the building's wastewater drainage system via an indirect drain.

The support structure for elevated tanks must comply with the stipulations of article 3.16.

6.5.1 DIMENSIONING AND DEVICES

When only an elevated tank exists, it is advisable that its capacity be at least equal to the total daily consumption of the installations. In cases where interruptions in supply are sporadic, the capacity of said tank may be reduced.

When it is necessary to use a combination of collection tank, lift pump, and elevated tank, in places where problems such as insufficient public aqueduct pressure or continuous interruptions in supply occur, the capacity of the tanks shall depend on the pumping period, the capacity of the pumps, and the consumption pattern of the building. If these data are not available, it is advisable that the capacity of the collection tank be at least 75% of the total daily consumption and that of the elevated tank not less than half of that consumption.

Storage tanks shall be equipped with the necessary devices for their correct operation, maintenance, and cleaning, such as an access hatch, inlet pipe with float valve or other automatic control mechanism, outlet pipe with gate or shut-off valve, ventilation pipe, overflow pipe protected against the entry of insects, and a cleaning pipe that discharges without causing flooding (see figures 6.6, 6.7, and 6.8).

The pipe connections to the tank shall be made in such a way that they do not cause breakage of its walls and keep the tank in its original condition. Connections in metal tanks must prevent electrolytic corrosion.

All fittings that need replacement or repair must be installed in accessible locations. Tank valves that remain below ground or floor level must be provided with a box, in accordance with the provisions of section 6.4.3.

The control of water levels in the tanks shall be done by means of automatic level control devices whose function shall be:

a. Stop the inlet flow to the tank when the liquid level in the elevated tank rises to the foreseen maximum level.

b. Start the pump when the water level in the elevated tank drops to half its height.

c. Stop the pump when the water level in the elevated tank rises to the foreseen maximum level.

d. Stop the pump when the water level in the collection tank drops to 15 cm above the suction strainer.

Underground and semi-buried tanks must be constructed with appropriate and durable materials, resistant to the load stresses they will be subjected to.

Every tank must have an access hatch allowing its inspection, cleaning, and eventual repair. It shall rise at least fifteen centimeters (0.15 m) above the floor or ground level and shall be located so that it cannot suffer contamination or cause flooding. If constructed with concrete, it must be reinforced concrete or made of concrete blocks duly reinforced, filled with concrete, and lined with cement mortar.

The additional capacity of storage tanks for fire control purposes must be in accordance with the provisions of the Reglamento General sobre Seguridad Humana y Protección contra Incendios (General Regulation on Human Safety and Fire Protection).

6.5.2 LOCATION AND PIPE DIMENSIONING

The vertical distance between the roof of a tank and the axis of the water inlet pipe must not be less than fifteen centimeters (0.15 m). In tanks where the lid covers its entire surface and there is direct access to the inlet devices, this distance may be reduced to ten centimeters (0.10 m).

The overflow pipe must have a diameter greater than that of the inlet pipe and be at least twenty-five millimeters (0.025 m) in diameter. This pipe must discharge in a visible location where possible spills are clearly noticeable.

The position of the overflow pipe shall be such that its crown is at the same level as the bottom of the inlet pipe. The distance between the bottom of the overflow pipe and the maximum water level shall be equal to the diameter of the overflow pipe and not less than twenty-five millimeters (0.025 m).

The drainage or cleaning pipe shall be located so as to allow complete emptying of the tank. It shall have a diameter of not less than twenty-five millimeters (0.025 m) and must be provided with a valve.

The supply pipe from the public supply to the elevated tank must be calculated to supply the total daily consumption in a time no greater than four hours.

This pipe must be provided with its corresponding shut-off valve. In the case of one or two-story buildings, the diameter of the supply pipe to the elevated tank may be selected according to the daily allowance and the capacity of the tank, per table 6.10.

Note:

1. Internal pipe diameter.

These diameters have been calculated assuming a time of four hours for filling the elevated tank.

Collection tanks must be kept as far away as possible from party walls and wastewater or storm sewers, the distance between edges being at least two meters (2.00 m).

No collection tank may be installed in a place subject to flooding or seepage of rain or wastewater.

6.6 PUMPING EQUIPMENT 6.6.1 GENERAL STANDARDS

The selection of pumping equipment shall be made based on its characteristic curves, its preferred operating region, and its acceptable operating region, as well as the operating conditions of the distribution system, correctly determining the operating points that correspond with the different operating regimes considered. The motor power must be in accordance with the hydraulic power requirements of the system.

For water pumping in buildings, the use of centrifugal pumps is generally recommended.

Pumps installed in buildings, intended for water supply, shall not be connected directly to the public network; only through a collection tank, as provided in article 6.1.8, subsections b and c.

6.6.2 DIMENSIONING

When the water distribution system is provided with a collection tank and an elevated tank, the capacity of the pumping equipment must be such that it allows filling the elevated tank within the time established in section 6.5.2-5.

The diameters of the pump discharge pipes shall be determined based on the pumping flow rate and the total dynamic head. The diameters of the pump suction pipes shall be determined according to the required net positive suction head of the pump.

The pump power may be calculated using the following equation:

The electric motors driving pumps must have a nominal power of 130% of that absorbed by the pump if they are three-phase, and 150% if they are single-phase. If precise technical data are available, the required power may be calculated taking such characteristics into account. These data should be understood as a guide and not as a requirement.

6.6.3 INSTALLATION

The pumping equipment for water distribution systems installed inside buildings must be located in suitable environments that satisfy requirements such as sufficient free space around the pump for its easy repair or removal, floor sloped towards provided drains, minimization of acoustic or noise pollution, safety, and adequate ventilation for the room. Equipment installed outdoors must be adequately protected against the elements and arranged in such a way that acoustic or noise pollution is minimized.

Pumping equipment must be installed on a concrete foundation, dimensioned to absorb vibrations. The equipment shall be fixed to the foundation by means of anchor bolts, in accordance with the recommendations of the pumping equipment manufacturer.

The pump connections to the suction and discharge pipes must comply with the following requirements:

a. The joints between the pump and the corresponding pipes shall preferably be of the flange or butt-joint type.

b. The joints immediately adjacent to the discharge pipes for diameters of thirty-two millimeters (0.032 m) and larger shall be of the flexible type.

c. The suction and intake pipes must rest on supports independent of the pump foundations. Their installation shall use the fewest possible number of elbows or fittings.

d. In the case of hot water recirculation pumps, expansion joints must be used on both the suction and the intake pipes.

e. The diameters of the suction pipes shall always be larger than or equal to those of the discharge pipes.

f. For pump testing purposes, it is recommended that the discharge have a provision in the form of a T-union with its respective gate valve.

g. It is recommended to install a pressure gauge on the discharge pipe, a short distance from the pump, whose capacity is in accordance with the pressure developed by the pump. Similarly, it is recommended to install a pressure gauge on the suction pipe, a short distance from the pump, whose measurement range is in accordance with the suction head that the pipe may experience.

h. If a diameter reduction is required on the pump suction, an eccentric reducer shall be used to prevent air accumulation.

On the discharge pipes, concentric reducers shall be used when necessary.

On the discharge pipe, immediately after the pump, a check valve and a gate valve must be installed.

On suction pipes with positive head, a gate valve shall be installed. In the event that it operates with negative suction head, to prevent loss of prime in the pump, a check valve (or foot valve) with its respective strainer must be installed at its lower end.

In high-capacity pumping systems or for elevated heads, the advisability of installing air-release valves, pressure relief valves, or some other system to counteract the effects of water hammer must be studied.

Pumps and electric motors installed in the water distribution systems of buildings must be identified with plates on which the data and characteristics thereof are indelibly engraved, such as:

a. For the pump: make, model, type, serial number, flow rate, pressure, speed, and hydraulic power b. For the motor: make, model, serial number, voltage and current per phase, power factor, service factor, speed, frequency, insulation type, class, and acceptable ambient temperature

Motors must have their own independent power supply derived directly from the control panel. The equipment must be provided with adequate protection against overloads, short circuits, phase loss, phase reversal, and overheating.

Pumping equipment for combined operation with collection tanks, hydropneumatic systems, and fire extinguishing systems must be equipped with an automatic control system that guarantees its adequate operation.

For pumping equipment used in buildings or facilities that so require, its connection to an alternate power system for emergency situations must be provided for.

All pumping equipment and water supply installations in buildings covered by this regulation must have a maintenance plan that ensures an adequate operating condition.

6.7 HYDROPNEUMATIC EQUIPMENT

In places where the public water supply does not guarantee sufficient pressure for the building's requirements, hydropneumatic equipment may be installed to maintain adequate pressure in the water distribution system. Hydropneumatic tanks must not be used for fire protection.

For the installation of hydropneumatic equipment, a low-level tank must be available with a minimum capacity for the total daily consumption of the building.

6.7.1 PUMPS

The pumps must be selected to satisfy the pressures required by the system, as established in section 6.3.1, including the operating range of the hydropneumatic tank.

For the maximum demand condition, it is recommended that the motor starts per hour for the pumping system do not exceed the manufacturer's recommendations. As a guide, the following values are suggested:

. Motors larger than 4 kW: 6 to 8 cycles/hour.

. Motors between 4 and 2 kW: 8 to 15 cycles/hour.

. Motors smaller than 2 kW: 15 to 25 cycles/hour.

The operating flow rate of the pump shall be equal to the maximum consumption of the installation served by the hydropneumatic system during the duration of the operating cycle. The maximum hourly consumption of the installation can be determined in two ways:

a. From the average daily flow rate established according to the allocations indicated in chapter 4, multiplied by a maximization factor of twenty (20) in the case of dwellings and ten (10) in the case of offices and commercial premises.

b. From the probable maximum instantaneous flow rate of the installation, which is established in section 6.3.3, according to the following expression:

6.7.2 HYDROPNEUMATIC TANKS

The pumps and motors of the hydropneumatic system must also comply with the requirements demanded in section 6.6, to the extent they are applicable.

The range of operating pressures of the hydropneumatic tank must guarantee that the maximum and minimum pressures in the system comply with the provisions of section 6.3.1.

The total volume of the hydropneumatic tank can be determined according to the following expressions:

The volume calculated according to the previous formulas includes an additional 10% to ensure the seal of the liquid inlet and outlet tubes. Furthermore, in the case of installations with a compressor, it includes an additional 10% as a safety margin against possible air losses in the system.

The minimum water level in the hydropneumatic tank must be such that it covers the water inlet and outlet connections, as well as prevents air from escaping through said connections. It is recommended that the volume of water occupied by the seal be not less than 10% of the total tank volume.

Hydropneumatic tanks must have an air charging system of the automatic type; tanks with a capacity equal to or greater than three thousand liters (3000 L) must have an air compressor for such purposes.

The capacity of the compressors for hydropneumatic systems must be such that it compresses a volume of air equal to the tank's capacity, from atmospheric pressure to the tank's minimum working pressure (Pmin), within a period of at least one and a half hours.

The hydropneumatic system must be equipped with the implements indicated below:

a. Automatic and manual control device b. Pressure switch for start-up at minimum pressure and shutdown at maximum pressure c. Pressure gauge on the water tank d. Safety valve e. Gate valves with butt-joint unions that allow the operation and dismounting of equipment and accessories f. Check valves on the pump discharge pipes to the hydropneumatic tank g. Gate valve placed in such a way that it can drain all the contents of the tank h. Automatic device to stop the operation of the pumps and compressor (if any) in case of lack of water i. Flexible unions to absorb vibrations j. A bypass system must be provided that allows the building to be supplied directly from the network, in case of breakdown or maintenance of the hydropneumatic system.

Figure 6.9 shows a model of a hydropneumatic system.

Hydropneumatic tanks shall be supported on adequate supports and, in addition, horizontal ones shall have sheets of insulating material placed on the supports to absorb the expansions they will be subjected to. These horizontal tanks shall be installed with a minimum slope of 1% towards the anticipated drain or cleanout.

6.8 INSPECTION AND TESTING OF DRINKING WATER SUPPLY INSTALLATIONS

Water supply installations must be inspected and tested before they are put into service.

To verify compliance with the approved project, the professional responsible for the work must inspect it regularly, according to the stipulations established in the CFIA regulations, demanding, in cases of alteration, any necessary corrections, as an indispensable requirement for approving the work.

The professional responsible for the work is obligated to test the system, as a guarantee of its good execution and design, according to the hydrostatic test described below:

a. The test must be carried out before installing the sanitary fixtures, placing plugs in the corresponding locations. The pipes to be tested must be free of foreign materials and debris.

b. Inject water with the help of a pump until a pressure of 700 kPa is achieved.

c. Observe that said pressure remains constant on the pressure gauge for a minimum period of fifteen (15) minutes, allowing a decrease of no more than 15 kPa without pump action.

d. If the pressure gauge indicates a pressure drop, look for the points of possible leaks, which must be properly corrected until the provisions of subsection c of this article are met.

e. For the safety purposes of the test, pressure gauges with sufficient sensitivity to indicate small pressure changes, on the order of 5 kPa or less, must be used.

In specific or special cases, the sanitary authority may subject the installations to any additional tests it deems pertinent.

6.9 SANITARY DISINFECTION

After the internal drinking water network or any part thereof has been installed or repaired, it must be washed and disinfected. The disinfection procedure, as long as the sanitary authority does not indicate another procedure, shall be the following:

a. The pipe system must be filled with drinking water until it overflows at the accessories. The pipes to be disinfected must be free of foreign materials and debris.

b. The system shall be filled using a solution of at least 50 mg/L of chlorine, which must act inside the pipe for at least three (3) hours.

During the chlorination process, all valves and other accessories shall be operated repeatedly to ensure that all their parts come into contact with the chlorine solution.

c. After disinfection, the chlorinated water shall be totally expelled from the pipe by filling it with water intended for consumption.

d. The process must be repeated if, through bacteriological examinations, the persistence of contaminating elements or a high chlorine concentration is verified.

Before carrying out the disinfection of storage tanks, they must be filled with water to detect leaks. In the case of concrete structures, it is recommended to waterproof the tank. Once leaks are detected, if any, the tank shall be drained and its repair carried out. Disinfection shall be performed as follows:

a. The walls of the tank shall be washed with a broom or steel brush, using a concentrated solution of calcium or sodium hypochlorite (150 to 200 mg/L).

b. The tank shall be filled with a solution containing at least 50 mg/L of chlorine and must remain in the tank for 12 hours, at a minimum. During this time, the valves must be operated repeatedly, so that these and the accessories also come into contact with the disinfectant.

c. After disinfection, the chlorinated water shall be completely drained from the tank.

d. When calcium or sodium hypochlorite is not available to perform the disinfection, other biocidal compounds could be used for the disinfection process, with prior authorization for their use from the competent sanitary authority. These compounds must have certification that they are not harmful to human health, granted by a global organization, for example the Organization for Health and Public Safety (NSF International).

6.10 HOT WATER INSTALLATIONS 6.10.1 GENERAL STANDARDS

For the production, storage, and distribution of hot water, the provisions of this section must be complied with, in addition to what is established in the previous articles for drinking water systems.

Hot water installations in buildings must satisfy consumption requirements and must not present accident risks.

Equipment for generating hot water shall be constructed in such a way that it is resistant to the maximum pressures and temperatures that may occur in the system, as well as being resistant to corrosion and equipped with all the required safety and cleaning devices according to current regulations and good construction practice.

All hot water generation equipment shall be provided with automatic devices for temperature control and for cutting off the energy source. Said devices must be installed in such a way that they suspend the energy supply before the water in the tank reaches a temperature of 60 °C for dwellings; 70 °C for restaurants, hotels, and similar; 80 °C for hospitals, clinics, and similar. The temperature sensor must be located in the area of maximum water temperature.

Hot water generation systems shall have safety valves to control excess pressure. Said devices shall be set to begin their operation at a pressure 10% greater than that of the system's normal operation.

Their location shall be on the generation equipment or on its outlet pipe at a maximum distance of thirty centimeters (0.30 m) from the equipment, provided there are no valves between the safety valve and said equipment.

Hot water generation systems that operate on combustible gas and are of the open type must not be installed in bathrooms, bedrooms, shower rooms, or cleaning rooms. In this type of enclosure, only those of the sealed type may be used.

6.10.2 INSTALLATION

The site where a water heater is installed must be accessible for its inspection, maintenance, or replacement.

Water heaters must be located in non-habitable rooms of the house, with the exception of instantaneous water heaters, provided they are electric or directly vented.

When the building's hot water supply system is of the simple type or without recirculation, a check valve must be installed on the hot water supply pipe.

A control valve must be installed on the cold water supply pipe to the hot water generation system. Furthermore, to separate the hot water tank from the pipes and facilitate its maintenance, the inlet and outlet connections shall be of the butt-joint union type.

Steam or hot water leaks from safety and control devices must be discharged indirectly to the drainage system. The discharges shall be located in such a way that they do not cause accidents, nuisances, or damage to structures, equipment, and properties, but that allows their observation by the building's occupants. The diameter of the discharge pipe must be at least the outlet diameter of the relief valve. The discharge pipe must allow gravity drainage and its final part must be at a distance no greater than fifteen centimeters (0.15 m) above the floor level.

Materials. In hot water systems, the distribution pipes may be made of galvanized iron, copper, or CPVC. Pipes of other materials may be used; however, the review by the competent sanitary authority and other State institutions must be kept in mind.

Sufficient expansion joints must be installed in the hot water system pipes to prevent buckling, excessive displacement, or rupture of the pipes.

Water heaters must be located at a distance no less than thirty centimeters (0.30 m) from any side or rear wall. This is in the event that the equipment manufacturer does not provide an indication in this regard.

Gas-fired water heaters installed in residential buildings must be installed in such a way that the burners or ignition devices are located at a minimum distance of fifty centimeters (0.5 m) from the floor.

Valves must be installed to control excess pressure, in addition to installing a check valve on the cold water supply pipe.

The installation of gas-fired water heaters must also comply with the stipulations of the NFPA 54 National Fuel Gas Code or NFPA 58 Liquefied Petroleum Gas Code.

The installation of electric water heaters must comply with the stipulations of the Costa Rican Electrical Code for the Safety of Life and Property or, in its absence, with the NFPA 70 National Electrical Code.

6.10.3 COMBUSTION AIR

Water heaters that use fuels must be installed in sites with good ventilation, which allow adequate combustion of the equipment and ventilation of the exhaust gases.

In buildings that exhibit high airtightness with respect to air infiltration, the combustion air must be obtained from outside. For buildings with ordinary airtightness, all or a portion of the air required for combustion may be obtained by infiltration, if the enclosed air volume is at least one cubic meter (1 m3) for every two hundred five watts (205 W) of heater capacity.

The net free area of openings or ducts to supply the necessary combustion air is presented in table 6.11.

Note:

An unconfined site is considered to be any room or place that has a volume of at least 1 m3 for every 205 W of water heater capacity. Rooms that communicate directly with this space, through openings without attachments, such as doors, are considered part of the confined site.

Openings for air intake must be located in such a way that:

. One opening must be located at a distance, above the highest part of the water heater, of not less than 30 cm.

. Another opening must be located below the ceiling level of the room, at a distance of not less than 30 cm.

. The openings must be larger in size than the heater, and must terminate at a minimum distance of 7.5 cm above the sides or front of the heater.

. The openings must serve a single enclosed room.

The requirements indicated in table 6.11 are only a reference. The manner in which combustion air is supplied may be designed according to recognized principles and good engineering practices, as long as it does not contravene the provisions of the related authorities.

6.10.4 VENTILATION AND COMBUSTION GASES

Water heaters that require chimneys or ducts to expel ventilation gases must comply with the provisions of the equipment manufacturer; in addition, for design and sizing, the indications of the NFPA 54, National Fuel Gas Code, may be used.

Chimney ducts must be adequate to carry the combustion gases and must comply with the specifications of the heater manufacturer, as well as the provisions of NFPA 54 National Fuel Gas Code.

The ventilation system must be designed so that it develops a positive flow that transports all combustion products to the outside of the building.

The discharge of ducts that pass through walls or exit onto the roof must terminate in an adequate type of vent cap, which must be installed according to the manufacturer's instructions.

The discharge of ducts that terminate on the roof must exceed by at least sixty centimeters (0.60 m) the highest point of the roof located within a radius of three meters (3 m).

The discharge of the ducts must terminate respecting the following dimensions:

a. It must be located at a distance no less than one hundred twenty centimeters (1.20 m) below any door, window (serving for ventilation purposes), or air inlets (by gravity).

b. It must be at a distance no less than one hundred twenty centimeters (1.20 m) horizontally from any door, window (serving for ventilation purposes), or air inlets (by gravity).

c. It must be at a distance no less than thirty centimeters (0.30 m) above any door, window (serving for ventilation purposes), or air inlets (by gravity).

d. It must be at a distance no less than ninety centimeters (0.90 m) above any forced air inlet, located within a radius of three meters (3 m).

e. It must be at a distance no less than sixty centimeters (0.60 m) above any wall or railing, located within a radius of three meters (3.0 m).

6.10.5 HOT WATER DISTRIBUTION AND STORAGE

Electric, gas, or solar energy water heaters may be used, whether of the direct-feed or tank type.

The drinking water supply for the heaters may be carried out by any of the following means:

a. Directly from the public network.

b. From a cold water collection tank.

c. From a hydropneumatic tank.

Hot water distribution may be carried out by means of the following methods:

recirculation system and non-recirculation system. The former may be of the forced type or by gravity.

. Recirculation system: this is recommended in buildings of three (3) or more stories, or in those cases where the sanitary fixtures or points where hot water is required are distributed over extensive areas, with special attention to cases where a constant and instantaneous water supply is necessary, such as hospitals, clinics, and hotels, among others.

. Non-recirculation system: it is used in small installations, single-family dwellings, and buildings of up to three stories.

The allocations for hot water shall be in accordance with what is established for cold water systems in chapter 4, as follows:

a. Domestic use. The minimum daily allocation shall be one-sixth of the allocation set for cold water.

b. Lodging and accommodation. The minimum daily allocation shall be one-quarter of the allocation set for cold water.

c. Restaurants and similar. The minimum daily allocation shall be two liters per person served.

d. Student residences. The minimum daily allocation shall be one-quarter of the allocation set for cold water.

e. Gymnasiums. The minimum daily allocation shall be five liters per square meter (5.0 L/m2) of effective area.

f. Hospitals, clinics, and similar. The minimum daily allocation for clinics and hospitals shall be two-fifths of the allocation set for cold water. The daily allocation for dental clinics shall be one-eighth of the allocation set for cold water.

For calculating the capacity of the hot water generation equipment, when it has a collection tank, the relationships indicated in table 6.12 shall be used, according to the assigned hot water consumption.

7. WASTEWATER DRAINAGE SYSTEMS 7.1 GENERAL STANDARDS

Wastewater sanitary installations must be designed and constructed in such a way that they allow the rapid evacuation of waste, avoid obstructions, prevent the passage of gases and odors from the system into the interior of buildings, do not allow the escape of liquids or the formation of deposits inside the pipes, and do not contaminate drinking water.

The pipes and accessories of the wastewater drainage systems shall be made of a durable material, free of defects, and shall comply with the requirements and specifications indicated in the articles of section 7.2 of this Code.

Each sanitary fixture or accessory connected directly to the wastewater drainage system must be equipped with a water seal or trap to prevent the entry of foul odors into the interior of the building.

Every wastewater drainage system must be equipped with a sufficient number of inspection and cleanout boxes for its cleaning and maintenance.

The wastewater drainage system must have vent pipes that allow adequate aeration, guaranteeing flow at atmospheric pressure.

No sanitary fixture shall be installed in a room that does not have adequate ventilation and lighting. In addition, the dimensions indicated in section 5.3 of this Code shall be respected.

The discharges from the wastewater drainage systems must be disposed of as indicated in chapter 3 of this Code.

The following conditions are inadmissible in a wastewater drainage system:

a. That the discharges from one building enter the pipes of another building.

b. That the drainage pipes cross through the interior of drinking water storage tanks, nor that they cross over the roof or covering slab of the same (see section 6.5.2).

c. Cleanout boxes in rooms or enclosed places.

d. Cross connections with other systems.

A device or perforated cover must be installed at the entrance of the drain pipe, where the largest opening must not be greater than 12 mm, which does not allow the entry of rodents into the buildings.

7.2 MATERIALS FOR DRAIN PIPES, VENT PIPES, THEIR JOINTS AND CONNECTIONS

In conduits for domestic or industrial wastewater drainage, pipes of the following materials must be used, according to the indications of the following articles.

. Cast iron . PVC (DWV) . Galvanized steel . Polyethylene . Concrete . Polypropylene

The use of galvanized steel or wrought iron pipes and connection fittings shall be permitted for drain conduits or branches, downspouts, and sanitary sewer lines of the building, provided they are used with the corresponding drainage connections of the same materials and are not placed underground. They must be kept at a height above the ground of at least fifteen centimeters (0.15 m).

The use of extra-strength vitrified clay shall be admissible only in buried pipes and for exceptional cases. Its use is not recommended due to its fragility. Neither shall it be used in those cases where the drain pipe is pressurized by a pump.

The use of concrete pipes shall be admissible only for collectors located outside the construction area and away from the structural foundations of the building, and must be located at a distance of no less than one (1) meter from the latter. In single-story buildings, the use of these materials shall be permitted even underneath the construction zone.

Drain pipes that conduct corrosive liquids and the corresponding vent pipes shall be constructed of corrosion-resistant material.

For all different types of pipes, connections, and accessories, with the exception of those manufactured from PVC and CPVC, as long as national industrial technical standards are not in force in the country for the different types of pipes, connections, and accessories, they shall be considered of satisfactory quality if they comply with the most recent specifications of qualified entities such as:

. American Water Works Association (AWWA) . American Standards Association (ASA) . American Society for Testing and Materials (ASTM) . British Standards Institute (BSI) . International Organization for Standardization (ISO) . Deutsche Institute fur Normung (DIN) In the case of PVC pipes, the corresponding of the following standards must be complied with, as applicable:

. ASTM D 3034 PVC pipe and fittings for sanitary sewer.

. ASTM D 2665 PVC pipe and fittings for drain, waste, and vent (DWV).

. ASTM D 3350 polyethylene pipe and fittings.

. ASTM F-949 corrugated (structured) wall PVC pipe and fittings with smooth interior.

Joints for waste and vent pipes shall be in accordance with the class and type of the respective pipes, and shall guarantee the watertightness of the system.

Polyethylene pipes may be exposed to ultraviolet radiation, provided they are stabilized by means of well-dispersed carbon black in a compound, at a concentration of no less than 2%.

PVC pipes may be exposed to the environment, provided they are in an area not exposed to physical damage and are protected from ultraviolet rays.

7.3 STANDARDS FOR THE SIZING OF WASTEWATER DRAINAGE PIPES 7.3.1 SIZING METHODS

The dimensions of the primary and secondary collectors shall be calculated based on the flow rate that each sanitary fixture discharging into them can discharge.

The maximum flow rate of a collector shall be obtained by considering the probability of simultaneous use of the sanitary fixtures connected to it. It is suggested to use either of the two methods indicated below:

a. First method: this consists of estimating the discharge flow rate in a manner similar to section 6.3.3, using fixture units as discharge units, but only the data for systems with flushometers shall be used. Once the probable maximum flow rate is obtained, the diameter of drains and stacks is estimated using the procedures indicated in section 7.3.

b. Second method: the second way consists of using tables that directly relate the discharge units in a drain pipe to the required diameter. Tables 7.1 and 7.2 are used for these purposes.

7.3.1.1 FIRST METHOD

Similarly to potable water supply systems, wastewater drainage systems shall be sized using the concept of the probable maximum flow rate.

Hunter's method, explained in section 6.3.3, may also be used to estimate wastewater discharge flow rates.

In this case, each sanitary fixture is assigned a weight using the discharge units of sanitary appliances. The value of the discharge units (see table 7.3) is based on the average volume discharged, the normal duration of the discharge, and the frequency of use of the sanitary appliance. In general, the discharge units of appliances are equal or similar to the fixture units indicated in table A1 (u.a.), except in those cases where the discharges of the appliances differ from their supply flow rates, such as tank-type water closets, sinks, among others. Table 7.3 indicates the discharge unit (u.d.) values for different types of appliances.

As a recommendation for estimating the flow rate from discharge units, the data for systems with flushometers may be used.

Once the probable maximum flow rate is obtained from section 7.3.2 and Hunter's method in section 6.3.3, the diameter of the drains and stacks is estimated using the procedures indicated in section 7.3.3.

7.3.1.2 SECOND METHOD

The second way consists of using tables that directly relate the discharge units in a drain pipe to the required diameter. Tables 7.1 and 7.2 are used for these purposes.

Notes:

1. Water closets are not permitted.

2. No more than two water closets are permitted.

3. No more than six water closets are permitted.

Notes:

1. Water closets are not permitted.

2. No more than two water closets are permitted.

3. No more than six water closets are permitted.

7.3.2 DISCHARGE UNITS AND MINIMUM DIAMETERS OF DRAIN PIPES

For the estimation of the discharge capacities of the different sanitary fixtures, as well as the minimum diameters of the traps and discharge pipes of said appliances, the values given in table 7.3 shall be used. For any appliance not appearing in said table, the data indicated in table 7.5 shall be used, in accordance with the discharge units.

Notes:

1. Minimum internal diameter 2. The use of seventy-five millimeter (0.075 m) pipes shall be permitted for six-liter (6.0 l) per flush water closets. Also, in buildings where the dimensions between the concrete slab and the ceiling are reduced.

3. For buildings where there are common laundry areas, with banks of three or more washing machines, at least six u.d. per machine shall be considered for the sizing of common drains, both horizontal and vertical.

5. In the case of devices or equipment with continuous or semi-continuous flow, such as the output from wastewater pumps, automatic car washes, air conditioning equipment and similar, the corresponding number of discharge units shall be calculated at a rate of one discharge unit for every 0.06 liters per second of flow. In the event of discharge from said devices or equipment whose drainage is carried out by pumping, the minimum diameter of the pipe or drain branch receiving such discharge shall be 7.62 cm (3").

3. The receptor of the indirect drain shall be sized based on the total discharge of the drain arriving at it, in accordance with table 7.4.

Note:

. For low-demand drains, for example refrigerators, coffee and water dispensers, a trap of at least 38 mm shall be used.

. For drains with moderate or considerable demand, for example commercial sinks and dishwashers, a trap of at least 50 mm shall be used.

7.3.3 SLOPES AND VELOCITIES

The slope of the horizontal reaches of the discharge pipes, as well as that of the primary and secondary collectors, shall be uniform. To determine their diameter and slope, the following considerations shall be taken into account:

a. The diameter of a horizontal drain pipe shall not be less than that of any of the outlet orifices of the fixtures discharging into it.

b. The pipe shall function as an open channel with velocities between 0.6 and 2.5 m/s.

c. For the design flow, the discharge shall fill, at most, half the height of the collector, under uniform flow conditions. In multistory buildings, the discharge may fill up to a maximum of 3/4 of the height of the collector, under uniform flow conditions.

d. For the estimation of the required diameter and slope, the Manning formula is recommended:

For the calculation of the wetted area and the hydraulic radius for the two flow conditions, the equations in table 7.6 may be used.

Note:

Where d is the internal diameter of the pipe (m).

e. In the case of discharge pipes and collectors of less than one hundred and fifty millimeters in diameter (0.15 m), the minimum slopes indicated in table 7.8 shall be respected.

7.4 CONSTRUCTION REQUIREMENTS FOR WASTEWATER DRAINS 7.4.1 INSTALLATION AND LOCATION

In buildings of three or more stories, stacks shall be placed in ducts provided for that purpose. Their dimensions shall be such that they permit their installation, inspection, repair, or removal.

Wastewater drain or vent pipes shall not be placed in stairways, elevator shafts, or in such a way as to obstruct the normal operation of windows or doors.

The placement of drain pipes directly above water supply tanks, the cleaning accesses of said tanks, or floor areas used for the manufacture, preparation, packaging, storage, or display of food shall not be permitted.

The installation of drain and vent pipes shall comply with the applicable articles of section 6.4.

The building's wastewater drain pipes and branches shall be installed in straight alignments and with a uniform slope.

Buried pipes. Drainage collectors located underground shall be placed in excavated trenches of dimensions such that they permit their easy installation and comply with the following conditions:

a. The depth of the trenches shall be in accordance with the diameter of the pipe to be installed, and under no circumstances shall there be a distance of less than thirty centimeters (0.30 m) between the crown of the pipe and the ground surface. In the event of a transit area, this distance shall not be less than one meter (1.0 m), unless calculations demonstrate that a lower value is safe.

b. Before proceeding with the placement of the pipes, the bottom of the trench must be compacted in order to avoid possible damage due to settlement.

The pipes must be in contact with firm ground along their entire length and in such a way that they are supported on at least twenty-five percent (25%) of their external surface.

c. When there are possibilities of earthworks (movimientos de tierra), the respective precautions shall be taken by setting the pipes on special bases and using flexible connections.

d. Once the pipes are placed, and the trench is backfilled and compacted, they shall be inspected and subjected to the corresponding tests in accordance with the stipulations in section 7.10.

e. No point of the wastewater collector shall be at a distance less than those indicated below:

f. The building's wastewater and stormwater drain pipes located at a lower level and parallel to the foundations shall be set back from them in such a way that the plane formed by the lower edge of the foundation and the axis of the pipe forms an angle no greater than forty-five degrees (45º) with the horizontal.

g. When the building's sanitary or storm sewer pipes are placed on fill land, cast iron pipes placed on a well-compacted base shall be used. Nevertheless, the use of other approved materials shall be permitted when the pipes are placed on a concrete base whose thickness and strength are in accordance with the depth and characteristics of the fill.

7.4.2 CONNECTIONS BETWEEN PIPES

Connections between collectors, stacks, and drain pipes shall be made at an angle no greater than forty-five degrees (45°), unless made in a manhole (caja de registro), in which case the bottom of the manhole shall be such that it conditions the flow.

To prevent the backflow from wastewater drain pipes into the branches, each branch connection to the drain pipe must preferably be made in its upper half or in the air space portion.

Where two or more wastewater stacks discharge into a main horizontal branch, they shall be connected to the upper half of the branch.

When a change of direction is required for a stack, the diameters of the inclined part and the lower section of the stack shall be calculated as follows:

a. If the inclined part forms an angle of 45 degrees or more with the horizontal, it shall be calculated as if it were a stack.

b. If the inclined part forms an angle of less than 45 degrees with the horizontal, it shall be calculated according to its design flow and as if it had a slope of 4%.

c. Below the inclined part, the stack shall have a diameter no less than that of the inclined section.

Horizontal changes of direction in wastewater drain pipes must be made by means of 45° Y-branches, long sweep elbows of 60°, 45°, or 22.5°, or with appropriate combinations of these fittings or their equivalents.

Changes of flow direction from horizontal to vertical shall be made through the use of:

a. Single or double sanitary T-branches.

b. 45º elbows with single or double 45º Y-branches.

c. 90º elbows.

d. Special connection fitting, previously approved by the competent health authority.

Changes of flow direction, from vertical to horizontal, shall be made through the use of:

e. Short-radius 90º elbows (radius less than 1.5 d), when the pipe diameter is greater than 75 mm, or long-radius 90º elbow (radius greater than 1.5 d), when the pipe diameter is 75 mm or less.

f. 45º elbows and 45º Y-branches.

The use of the connection fittings indicated below for connections or changes of direction in the building's wastewater and stormwater drainage systems is prohibited:

a. Elbows of more than 45º.

b. Straight T-branches, at 90º, in any conduit, except in vent pipes.

c. Sanitary T-branches, single or double, in connections or changes of direction from horizontal to horizontal at 90º. These fittings may be used in changes of direction from horizontal to vertical, when installed preceded by 45º elbows.

d. Double Y-branches at 45º, for connections or changes of direction from horizontal to horizontal, unless they are equipped with a cleanout plug located directly upstream of the respective connection.

e. Connection fittings equipped with a bell located in the direction opposite to the flow.

f. Elbows provided with a side or back connection, when the latter is horizontal.

7.5 TRAPS

Every sanitary fixture shall be equipped with a trap (sifón) whose water seal shall have a height of no less than five centimeters (0.05 m) nor more than ten centimeters (0.10 m), except in those cases where the height of the seal to be used is specified, or where its special design requires a water height not contemplated within the scope established in this article.

Traps shall be placed as close as possible to the discharge orifices of the corresponding sanitary fixtures, but at a vertical distance no greater than sixty centimeters (0.60 m) between the discharge orifice and the weir of the trap.

Under no circumstances shall the nominal diameter of the trap be less than that specified in table 7.3.

For special fixtures, such as laundry sinks, kitchen sinks, and other similar fixtures with two or three compartments, or in the case of three washbasins close together in the same room, the use of a common trap shall be permitted, provided the following requirements are met:

a. The bottom of any of the compartments shall not be more than fifteen centimeters (0.15 m) below the bottom of the others.

b. The horizontal distance between the trap and the discharge orifice of the farthest compartment shall not be greater than seventy-five centimeters (0.75 m).

c. In the case of three-compartment fixtures, the common trap must be placed below the central compartment.

The use of a common trap shall be permitted for a maximum of five of the following sanitary appliances: showers and floor drains.

The traps of sanitary fixtures shall be equipped with a cleanout plug, unless the trap is easily removable or forms an integral part of the fixture.

The use of traps in which the seal depends on the action of levers or any moving part is prohibited. The use of S-type, bell-type, or bottle-type traps is also prohibited. No fixture shall have more than one trap.

Floor drains (sumideros) shall have their water trap, installed in such a way that it allows access for cleaning. Their sizing shall be in accordance with the existing needs. When the floor drain has the probability of being exposed to backflow, the drainage system must have a check valve.

7.6 CLEANOUTS AND MANHOLES

Wastewater, stormwater, and industrial wastewater drainage systems shall be equipped with cleanouts (bocas de limpieza) and manholes (cajas de registro) in accordance with the provisions established in the following articles.

7.6.1 CLEANOUTS

Cleanouts shall be located in easily accessible places.

Cleanouts shall be placed in accordance with the following indications:

a. When there are no manholes, at the beginning of each horizontal drain branch of a bank of sanitary fixtures, or in horizontal sections into which other branches have discharged.

b. In horizontal drain pipes, every ten meters (10 m).

c. At the foot of each stack, except when it discharges into a straight collector with a manhole located no more than five meters (5 m) from the foot of the stack.

d. In the lower part of the traps of sanitary fixtures, in accordance with the provisions of article 7.5.6.

e. In horizontal drain pipes, every two changes of direction (every 180°).

f. In stacks, at least every two floors.

g. Exceptions:

1. The cleanout may be omitted in horizontal drains of less than one hundred and fifty centimeters (1.5 m) in length, unless this line is serving a sink or a urinal.

2. In horizontal drains with a slope such that it forms an angle equal to or greater than 18° with respect to a horizontal line, except in pipes leading to grease traps.

The trap of a sanitary fixture shall be accepted as equivalent to a cleanout, provided it is easily removable.

Cleanouts shall be pieces of cast iron, bronze, PVC, or any other acceptable material, and shall be provided with a plug at one of their ends. The plugs shall be of the aforementioned materials, threaded, and provided with a slot or a projection to facilitate their removal.

In pipes with a diameter of less than one hundred millimeters (0.10 m), cleanouts shall be of the same diameter as the pipe they serve; in those of larger diameter, cleanouts of at least one hundred millimeters (0.10 m) shall be used.

When pipes are concealed or buried, they must be extended using forty-five-degree connections, until they end flush with the finished wall or floor, or they shall be housed in floor access boxes of dimensions such that they permit the removal of the plug and the effective cleaning of the system.

These access boxes shall be provided with suitable, easily removable covers, made of metal or concrete (see figure 7.1).

In floor access boxes, both the cover and the upper edge of the body must be flush with the finished floor. These access boxes must be located at a distance of no less than six meters (6.0 m) from any access door.

To prevent the outflow of wastewater, cleanouts shall be installed in such a way that they open in the direction opposite to the flow and form an angle of forty-five degrees (45º) with the drain pipe.

The minimum distance between the plug of any cleanout and a wall, ceiling, or any element that could hinder the cleaning of the system shall be forty-five centimeters (0.45 m) for pipes of one hundred millimeters (0.10 m) or more in diameter, and thirty centimeters (0.30 m) for pipes of seventy-five millimeters (0.075 m) or less. Figure 7.1 illustrates the different positions of cleanouts.

No sanitary fixture or floor drain shall discharge into the cleanouts.

7.6.2 MANHOLES

It is recommended that the connection of the wastewater drain to the public network be made by means of a manhole (caja de registro) with a building trap (sifón de edificio). This trap must be equipped with two cleanouts of the same diameter as the trap, and not less than one hundred millimeters (0.10 m). The cleanouts must be accessible, so as to allow cleaning the interior of the trap and cleaning upstream and downstream of it. Figure 7.2 shows a model of said manhole.

As far as possible, this manhole should be installed within the property line.

The building trap must be placed downstream of all drainage branches of the building, except those placed to receive discharges from oil separators, or from a wastewater lift system.

Venting must be provided for the building trap at a distance no greater than one hundred and twenty centimeters (1.20 m). It must have a diameter of at least half the diameter of the building drain at the point of connection, but not less than fifty millimeters (0.05 m). This vent must extend from the point of connection to the atmosphere outside the building, as specified in section 8.3 regarding venting systems.

Manholes shall be installed in the external pipe networks at every change of direction, slope, or diameter, at every connection with a branch, and every ten meters (10.0 m) in straight reaches. In drains passing underneath a building, manholes shall be installed at the entrance and exit of the building pipe.

Manholes shall be constructed with impermeable materials and may be made of concrete or masonry, with a frame and cover of cast iron, bronze, or concrete, or other materials that prove to have the necessary characteristics to form part of the system.

The interior of the manholes shall be smoothed so that they do not present rough or coarse surfaces. Manholes constructed with masonry must have a rendering of at least one centimeter in thickness (0.01 m). The bottom of the manholes must have half-channels of the diameter of the pipes to which they connect (see figure 7.3).

The covers must withstand the loads from the traffic to which they will be subjected. The final finish of their surface may be of another material in accordance with the floor in which they are installed. The cover must seal to prevent the escape of gases and odors. In the event that the foregoing cannot be guaranteed, a double cover or inner cover shall be used.

The dimensions of manholes shall be determined according to table 7.10. In addition, the following aspects must be taken into account:

a. The minimum separation between the pipe and the walls of the manhole shall be seventy-five millimeters (0.075 m).

b. In single-branch connections, the minimum width of the manholes shall be given by the diameter of the larger pipe plus thirty centimeters (0.30 m), distributed as ten centimeters (0.10 m) and twenty centimeters (0.20 m) of separation between the pipe and the walls (see figure 7.3).

c. In two-branch connections, the minimum width of the manholes shall be given by the diameter of the larger pipe plus forty centimeters (0.40 m), so that the separation between the pipe and the walls is at least twenty centimeters (0.20 m). These must enter the manhole opposite one another.

7.7 INDIRECT WASTES

Wastes from equipment and fixtures in which an obstruction of the wastewater drainage system into which they discharge may cause contamination shall discharge into the drain pipes indirectly. The following equipment must have indirect wastes:

a. Sterilizers, autoclaves, and any similar container or equipment used in laboratories, hospitals, clinics, and similar establishments.

b. Commercial refrigerators, freezers, ice-making machines, coffee dispensers, water dispensers, drinking fountains, and other similar equipment.

c. Overflow and cleaning pipes from potable water storage tanks, hydropneumatic tanks, swimming pools, and pumping systems in general.

d. Pipes from devices and equipment equipped with pressure or temperature relief valves from hot water generation or storage systems or steam installations.

e. Dishwashers, sinks, and equipment used for the preparation, preservation, and dispensing of food and beverages in soda fountains, bars, restaurants, and food product factories.

f. Any device or equipment that is not considered a plumbing fixture but is equipped with some form of pumping, or that has a drip or any drainage outlet.

g. All those drains that the respective health authority deems appropriate to safeguard public health.

The indirect waste shall be carried out in accordance with the following guidelines:

a. The discharge pipe from the fixture shall be led to a manhole, floor drain, funnel, or other suitable receptor device.

b. The discharge pipe shall be equal to or greater than the fixture's drain pipe, but never less than twenty-five millimeters (0.025 m). In the case of refrigerators and ice-making machines, the drain pipe shall not be less than eighteen millimeters (0.018 m).

c. A free space must be left between the outlet of the discharge pipe and the receptor device, which shall not be less than twice the diameter of the discharge pipe. This separation must be adequate to prevent contamination due to the backflow of wastewater.

d. Except for refrigerators and ice-making machines, the receptor device must be located at a distance no greater than four and a half meters (4.5 m) from the waste outlet of the fixture or equipment.

e. The drain pipe of the receptor device must be provided with its respective water seal and vent connection.

Figure 7.4 shows typical schematics of indirect wastes.

The receptor devices for indirect wastes shall be of such shape and capacity as to prevent splashing or flooding; in addition, they must be installed in well-ventilated places and easily accessible for inspection and cleaning. No receptor shall be installed in a bathroom or toilet room, or in any area of the building that is for general use by the occupants. These devices shall be equipped with removable gratings or covers when necessary to protect the safety of individuals.

With the exception of what is indicated in this section, indirect wastes shall comply with the applicable sections regarding drainage and venting of this Code. No vent pipe from an indirect waste may be combined with any vent pipe from the drainage system.

Indirect waste pipes that are longer than one and a half meters (1.5 m) and shorter than four and a half meters (4.5 m) must have their own trap, which does not require venting. If changes of direction are made in this pipe, cleanouts must be provided.

Floor drains serving cold storage rooms may be connected to a drain line that discharges into a receptor outside the floor area. The fill level of the receptor must be at least fifteen centimeters (0.15 m) below the lowest point of the floor drain. Each floor drain must have its own trap and individual vent. Cleanouts must be installed if changes of direction of at least ninety degrees (90°) are made.

7.1.1 DRAINAGE OF CONDENSATE, STEAM, AND HOT WATER

No steam or hot water pipe (temperature greater than 60 °C) shall be connected directly to the drainage system. The discharge pipe from hot water or steam generators must be arranged as indicated in the Boiler Regulation, in such a way as to prevent the entry of pressurized condensate by using a blow-off pit or any other means approved by the health authority. Blow-off pits that drain into the building's drainage system must have adequate ventilation, and the drain must have a deep seal trap that extends fifteen centimeters (0.15 m) below the pit.

The drain pipe of the blow-off pit and the vent pipe may be chosen based on the size of the generator's blow-off line, as indicated in the following table.

Floor drains, pits, or intercepting tanks constructed of concrete must have walls at least ten centimeters (0.10 m) thick, with an internal cement rendering of no less than thirteen millimeters (0.013 m) in thickness.

Floor drains or pits must have adequate access for cleaning.

The volume of water to be maintained in the pit shall not be less than twice the amount of water blown off from the boiler or boilers.

7.7.2 INDUSTRIAL WASTEWATER DRAINAGE

All those wastewaters that may damage or increase the maintenance costs of the sanitary drainage system, or that may affect the treatment processes, must be treated beforehand, before being discharged into the sanitary drainage system of the buildings. The piping system that transports these waters, from their point of origin to the treatment systems, must be of adequate design and materials, so as to satisfy the requirements of the competent sanitary authority. The discharge pipes leaving the treatment systems or the interceptors must comply with the requirements of common drains.

Any pipe that receives the discharge from fixtures that drain acidic or corrosive chemical substances must be made of suitable materials, such as chemically resistant glass, silicon-coated cast iron pipe, or vitrified clay, among others. All joints must be of the approved type and material.

Where practical, all such pipes must be accessible and installed as far as possible from other pipes or equipment.

No chemical waste vent pipe shall be connected to the general venting system.

The provisions of this section are not necessary in small photography installations, X-ray darkrooms, or small research laboratories where minimal quantities of adequately diluted chemicals are discharged.

7.8 INTERCEPTORS

When wastewaters contain greases, oils, flammable materials, acidic or alkaline substances, sand, earth, or any other objectionable solid or liquid that could affect the proper functioning of the building's pipes or the public sanitary and stormwater collectors, the installation of interceptors or separators shall be necessary.

The capacity, type, dimensions, and location of the interceptors or separators shall be adequate to create optimal conditions for the separation of the objectionable solids or liquids referred to in the preceding article.

Interceptors shall be located in places where they can be easily inspected and cleaned, and, to the extent possible, outside the buildings. Placing machinery or equipment on top of or immediately adjacent to them that could impede their proper maintenance shall not be permitted. The inspection opening shall be of such a dimension as to allow the entry of a person and must be sealed to prevent the escape of gases and odors.

7.8.1 GREASE INTERCEPTORS AND TRAPS

Separators or grease traps shall be installed in the drain lines of sinks, dishwashers, or other sanitary fixtures installed in restaurants, hotel kitchens, hospitals, and similar establishments, where there is a risk of a sufficient quantity of grease entering the drainage system to affect its proper functioning. The installation of these shall not be necessary in single-family dwellings.

Grease interceptors and traps must comply with the following general requirements:

a. They must be installed in such a way as to be easily accessible for cleaning and near the fixture that discharges the greasy waste. Cleaning consists of the complete removal of all contents, including floating materials, waste water, sludge, and solids. Cleaning shall be the responsibility of the user, who must perform it periodically in order to maintain efficient operation.

b. It shall be of adequate size to ensure a sufficient water surface area for the rapid cooling and solidification of the grease. The minimum retention time shall be twenty-four minutes (24 min), based on the actual maximum flow rate.

c. It shall have submerged inlet and outlet so that the grease can float on the surface without being disturbed by the discharge. It is recommended to install a T-fitting at both the inlet and outlet, which shall have a diameter of at least seventy-five millimeters (0.075 m). The inlet T-fitting shall extend into the liquid by at least twenty-five percent (25%) and the outlet T-fitting by at least fifty percent (50%).

d. The inspection cover must be sealed.

e. It shall have adequate ventilation that allows flow through the unit without creating odor problems. The vent pipe must be at least fifty millimeters (0.050 mm).

f. It is recommended that a perforated stainless steel tray, with handles to facilitate grease removal, be installed at the bottom of the trap.

g. It must have a total depth of at least eighty centimeters (0.80 m), leaving a free space between the liquid level and the top of at least twenty centimeters (0.20 m).

h. The length-to-width ratio must be between 2:1 and 3:2.

i. It shall have a low-velocity flow in the outlet pipe.

j. It shall have access openings above the inlet, the outlet, and in each internal compartment of the grease interceptor.

k. The level difference between the inlet and outlet pipes must not be more than five centimeters (0.05 m).

l. Designs with an attached deposit for grease storage may be accepted when the total capacity exceeds six hundred liters (0.6 m3) or where the establishment operates continuously for more than 16 hours per day.

m. The grease trap and the grease storage compartment shall be connected through an overflow weir, which must be 0.05 m above the water level. The maximum grease accumulation volume shall be at least 1/3 of the total volume of the grease trap. See diagram in Figures 7.5 and 7.6.

Grease interceptors must have at least two compartments; grease traps shall have only one. The intermediate separation wall shall be located at a distance between 2/3 and 3/4 of the total length from the inlet wall. Communication between the chambers shall be carried out by means of a long-radius elbow or tee, of the same size as the inlet tee, but not less than one hundred millimeters (0.10 m), placed on the inlet compartment side. This fitting shall be installed at a minimum height equivalent to 28% of the liquid height and at a maximum of 50%.

Furthermore, all interceptors and traps must have a small chamber at the outlet, which allows the taking of effluent samples for analysis.

Grease traps must have a trap (sifón), which shall have a water seal of at least five centimeters (0.05 m).

A grease trap may be used for the service of a single fixture when the horizontal distance between the fixture outlet and the trap does not exceed one meter and twenty centimeters (1.20 m) and the vertical distance is less than seventy-five centimeters (0.75 m).

The selection of a grease trap's size must be based on its efficiency and the type and number of fixtures from which it receives discharge. A minimum capacity of 9.5 liters per person served is sufficient to carry out proper grease separation. The minimum permissible capacity must be approximately four hundred and seventy liters (470 L) for small installations serving up to 50 people. In smaller installations that use a septic tank, it may be more economical to use a larger septic tank (fosa séptica).

Every fixture discharging into a grease trap must have its own trap and respective vent.

In the case of interceptors installed far from the fixtures they serve, the guidelines of Appendix A may be followed.

7.8.2 SOLIDS AND FLOATING OBJECTS INTERCEPTORS

Solids interceptors must be installed in places such as bottling plants, laundries, slaughterhouses, factories, and other establishments subject to the voluntary or accidental discharge of materials such as sand, earth, glass, hair, threads, animal viscera, feathers, or other solids into the drainage system (see Figure 7.7).

The solids interceptor must be installed whenever the sanitary authority responsible for discharges into the sewerage system (Ministry of Health, AyA, municipalities) deems it necessary.

Floor drains from multiple floors may discharge into a single solids interceptor.

The interceptor must comply with the following requirements:

a. It must be constructed of brick, concrete, or other hermetic material. The interceptor must have an interior baffle (deflector) so that it forms at least two compartments.

b. The inlet pipe to the interceptor and the outlet pipe must be of the same size, and not less than seventy-five millimeters (0.075 m). Two openings of the same size as the outlet pipe must be made in the baffle (deflector).

c. It must have a water seal of at least fifteen centimeters (0.15 m) on the effluent side.

d. It must have a minimum dimension of two thousand square centimeters (0.2 m2) of net opening area for the inlet section, and a liquid depth of sixty centimeters (0.60 m) as a minimum.

e. For every nineteen liters per minute of inlet flow (19 L/min), above a flow rate of seventy-five liters per minute (75 L/min), the area of the interceptor's inlet section must be increased by nine hundred square centimeters (0.09 m2).

f. The outlet section must have a minimum area equal to 50% of the area of the inlet section.

g. In places where there is also a carry-over of liquids, oils, or floating solids, the pipe of the outlet section must extend into the liquid by at least 50% of the height of the liquid level.

Solids interceptors of a design different from that set forth in this section may be installed, provided the objective of this section is met and the requirements of the sanitary authority responsible for ensuring compliance with the current standards regarding discharges into the sewerage system (Ministry of Health, AyA, municipalities) are satisfied.

7.8.3 FUEL INTERCEPTORS

Fuel interceptors (oil, gasoline, diesel, and similar) must be installed in the drainage system of buildings where there is a possibility of introducing oil or other flammable material into the drainage system, whether accidentally or voluntarily, such as service stations, mechanical workshops, vehicle washing stations, and other buildings at the discretion of the sanitary authority. The installation of fuel interceptors shall be subject to the situations described in Table 7.7 (see Figures 7.8 and 7.9).

Interceptors must comply with the following requirements:

a. Adequate ventilation must be installed for each compartment, by means of a vent pipe of at least fifty millimeters (0.050 m).

b. The ventilation shall be independent of the building's pipe ventilation system and must project at least three meters (3.0 m) above the floor level where it is projected, so that it is at a safe distance from any source of ignition.

c. Under no circumstances shall the discharge of water from sanitary fixtures into the fuel interceptors be permitted.

d. The interceptor must be vented on the drain side. This vent pipe must not be connected with those venting the compartments.

e. The minimum diameter of the discharge pipe must be at least seventy-five millimeters (0.075 m).

f. In the event that the interceptor requires an overflow pipe, a pipe of no less than fifty millimeters (0.050 m) must be installed, which shall discharge into a tank suitable for the storage of the waste liquids, with a capacity of no less than two thousand liters (2000 L).

g. The liquid level in the interceptor must have a minimum height of sixty centimeters (0.60 m).

h. The inlet pipe must not have any fittings. The outlet pipe must be submerged in the liquid by at least 80% of the height of the liquid level. In the case of single-section interceptors, which are also used for collecting solids, the outlet pipe must be submerged less than 80%, depending on the type and quantity of solids to be retained, but must not exceed 65% of the height of the liquid level.

i. The pipe entering the interceptor must have a water seal of at least thirty centimeters (0.30 m) in height.

j. In cases where it is convenient, a check valve (válvula de contraflujo) may be installed on the interceptor's discharge pipe.

In places where no more than three automobiles are kept or serviced (repaired or washed), a single-chamber interceptor must be installed, whose capacity must not be less than two hundred liters (200 L). For a greater number of cars, thirty liters (30 L) per each vehicle must be added to the previous capacity, up to ten (10) vehicles.

Exception:

. Compliance with this article is not required in multi-family buildings where there is parking for keeping fewer than five cars.

. Those establishments where the sanitary authority indicates otherwise.

In automobile parking places, the capacity of the interceptor shall be proportional to the surface area that will be drained to the interceptor, such that it shall have a capacity of one hundred and seventy liters (170 L) for the first two hundred and eighty square meters (280 m2). For every additional ninety-two square meters (92 m2) of surface area to be drained, the interceptor capacity shall be increased by twenty-eight liters (28 L).

The capacity of an interceptor installed in a washing center or automotive workshop shall be proportional to the building area that will be drained to the interceptor. For every ten square meters (10 m2) of surface area to be drained, the interceptor shall have an effective capacity of thirty-two liters (32 L), and must have a capacity of no less than two hundred liters (200 L).

Interceptors to be installed in service stations must comply with the requirements dictated in the regulation of the hydrocarbon storage and marketing system (see Figure 7.8).

7.9 WASTEWATER AND RAINWATER PUMPING

When wastewater or rainwater from the building cannot be discharged by gravity to the respective public network, a pumping system must be installed for its automatic discharge to said network (see Figures 7.10 and 7.11).

The pumping equipment must be installed in a location protected against flooding, easily accessible, well-ventilated, and with ample facilities for its inspection and maintenance.

The pumping equipment shall be of specific design for wastewater.

Wastewater and stormwater pumping wells or stations must be impermeable, with smooth walls, resistant to internal and external pressures, and resistant to the potential chemical actions that the contained water may produce. The connections of the pipe to the pumping well shall be such that they do not produce leaks or breakage of its walls.

For sizing the well, the following recommendations may be used:

a. In general, the retention time of wastewater in the well must be a maximum of ten (10) minutes.

b. When the discharge is estimated to be less than the average discharge, it is advisable to adopt a retention period equal to or less than 30 minutes, since if the retention time were longer, bad odors, gas release, and sludge accumulation at the bottom would occur.

c. It is recommended that the difference between the maximum and minimum water level not be greater than one meter. However, in small pumping stations, a smaller value may be adopted, with prior technical and operational justification for the case.

d. The relationship between the operating periods, the pumping flow rate, and the flow rate arriving at the well are shown below:

e. The useful capacity of the well is the portion between the axis of the incoming wastewater pipe and an elevation located at a minimum distance of three times the diameter above the pump inlet mouth or the suction pipe, if one exists.

f. The bottom of the well must have as small a surface area as possible to minimize solid deposits.

The wastewater pumping well must comply with the following requirements:

a. Its capacity shall be no greater than the volume equivalent to 12 hours of the average daily flow rate, nor less than the equivalent to four hours thereof.

b. It must be provided with a vent pipe, which shall extend above the floor at a height of at least two and a half meters (2.5 m), or it may be integrated into the building's venting system, provided conditions allow it.

The vent pipe must be capable of maintaining atmospheric pressure conditions inside the well, under normal operating conditions. The dimensioning of the vent pipe shall be carried out according to what is indicated in Section 8.10.4, but it must never be less than thirty-eight millimeters (0.038 m) in nominal diameter. In pumping systems where ejector systems are used, the well's vent pipe must not be combined with any other vent pipe.

c. It shall be equipped with a metallic cover, sealed with a rubber gasket or other similar material, so that it allows access for cleaning, maintenance, and repairs.

d. It shall be equipped with an access ladder.

e. It shall be equipped with a relief and overflow pipe.

f. When there are two wells, one for receiving the wastewater, called the "wet well", and another for the installation of the pumps, called the "dry well", the dry well must have natural or mechanical ventilation in those cases where, due to its depth and characteristics, it may present gas accumulation problems.

g. Facilities must be provided to eliminate water that may accumulate in the dry well.

h. The bottom of the well must have an inclination of between 30º and 45º (55% to 100%) towards the pump suction mouth.

Pumps for wastewater pumping systems must comply with the following requirements:

a. Be of special design so that during their operation, adequate protection against obstructions is guaranteed. It is recommended that the impellers be open.

b. Its capacity must be at least twice the maximum flow rate that the pumping well receives.

c. Flow rates shall be determined according to Sections 7.3.1.1 and 7.3.2 d. The pump suction pipes must be installed in a manner that avoids excessive turbulence near the suction point. For dimensioning purposes, it is advisable to adopt velocities that do not exceed one hundred and fifty centimeters per second (1.5 m/s) in the suction section and two hundred and forty centimeters per second (2.4 m/s) in the discharge section.

Under no circumstances shall the diameter of the suction pipe be less than one hundred millimeters (0.10 m).

e. It is recommended that the pump operating periods be a maximum of three to five starts per hour for vertical and horizontal pumps.

For submersible pumps, the permitted number of starts per hour is a maximum of ten for small pumps. For large pumps, the time of one operating cycle must not be less than twenty (20) minutes. The operating cycle must never be less than five (5) minutes.

f. The pump's discharge pipe must be connected to the building's drain collector at a minimum distance of three meters (3.0 m) from the nearest downspout downstream of the connection, in order to prevent turbulence and air entry into the line.

g. The pipes shall be equipped with gate valves to remove or install the equipment, and with check valves to prevent reverse flow. For sizes greater than one hundred millimeters (0.01 m), these valves must have a cast iron body, and for smaller sizes, the body must be cast iron or bronze.

h. The pipes shall be installed in a way that avoids noise and the transmission of vibrations. The joints between the pump and the discharge pipe shall be of the flexible type.

i. The pumping equipment shall be adequately fixed by means of plates, bolts, and damping joints to prevent the transmission of vibrations and for easy removal.

j. To determine the pump's operating time and frequency, the characteristics of its motor must be considered. As a general rule, it is recommended that the pump operating time not be less than two minutes (2.0 min.) and that its operating frequency be less than five times per hour.

k. It must comply with what is dictated in Sections 6.6.2 and 6.6.3, in the articles that apply.

The motors of the pumping equipment must have automatic controls activated by the levels in the pumping well. Manual controls shall also be provided. The well must be emptied to the established minimum level each time the equipment operates.

Likewise, safety devices for over-levels must be provided.

When the normal energy supply cannot guarantee continuous service to the pumping equipment, the equipment must have an alternate energy source.

When wastewater contains greases, oils, flammable materials, sand, or other objectionable solids or liquids, the installation of interceptors before the pumping well shall be mandatory. These interceptors shall comply with the provisions of Section 7.8.

In the case of pumping stations that receive the discharge from toilets (inodoros) and urinals (mingitorios), they must also comply with the following:

a. It must have a discharge capacity of at least seventy-five liters per minute (75 L/s).

b. In single-family dwellings, the pump or ejector must be capable of handling solids with a diameter of thirty-eight millimeters (0.038 m). The discharge pipe must be at least fifty millimeters (0.05 m) in diameter.

c. In other buildings, the pump or ejector must be capable of handling solids with a diameter of fifty millimeters (0.05 m). The discharge pipe must be at least seventy-five millimeters (0.075 m).

The drainage collectors that receive the discharge from any pump or ejector must be adequately dimensioned to prevent any overload. For every seventy-six milliliters per second (0.076 L/s) of flow rate from the pumping equipment, two fixture units must be added for drain sizing.

In the case of public-use buildings, two pumping systems or ejectors must be installed, in such a way that they work independently from one another, as a form of prevention against any mechanical failure or system overload.

7.10 INSPECTION AND TESTING OF WASTEWATER DRAINAGE SYSTEMS

Wastewater drainage systems must be inspected and subjected to the tests specified in this section. Compliance with this requirement shall be the responsibility of the professional responsible for the work.

Wastewater drain branches, downspouts, and collectors shall be subjected to the water test or the air test as described in the following articles. These tests may be performed per sections or for the entire system.

For the water test, the following procedure shall be followed:

a. No sanitary fixture shall be installed. The pipes to be tested must be free of foreign materials and debris.

b. Plugs shall be placed in all openings of the pipe to be tested, except at the highest point.

c. The pipe is filled at the highest point; after a reasonable time to account for water absorption losses, the pipe is filled until it overflows.

d. The pipe must be subjected to a pressure of no less than twenty-nine thousand four hundred pascals (29.4 kPa).

e. The sections or the system shall be accepted when the water volume remains constant for fifteen minutes. If the result is not satisfactory, the necessary corrections shall be made and the test repeated until leakages are not evident.

For the air test, the following procedure shall be followed:

a. A compressor is connected to one of the openings of the section or system, closing the rest of them.

b. The section or system is subjected to a uniform pressure of thirty-five thousand pascals (35 kPa).

c. The tested sections or system shall be accepted when the pressure does not drop within fifteen (15) minutes, once the compressor is deactivated. If the result is not satisfactory, the necessary corrections shall be made and the test repeated until there are no evident leakages.

Complementary works, such as wastewater tanks, septic tanks, interceptors, separators, inspection boxes, and catch basins (ceniceros) must be subjected to a water test in the following manner:

a. They are filled with water and a reasonable time is allowed to account for absorption losses.

b. They shall be filled again and left to rest for 48 hours, after which the water level must not drop more than twenty-five millimeters (0.025 m).

8. SANITARY VENTING 8.1 GENERAL STANDARDS

The wastewater drainage system of every building must be provided with an auxiliary vent piping system, designed in such a way that the gases and odors from all the drainage pipes circulate upward and escape to the atmosphere above the building. Furthermore, this system must allow the entry and exit of air from all parts of the system, so that conditions of siphoning, aspiration, or backpressure do not cause a loss of the trap seals.

The diameters, layout, and installation of the vent pipes must be chosen in such a way as to limit the pressure variation in the wastewater drainage system to a maximum of two hundred and forty-five pascals (245 Pa), above or below atmospheric pressure.

The pipes of the venting system, their joints, and connections must comply with what is specified in Section 7.2, in the articles that are applicable.

The water seal of every sanitary appliance shall be protected against siphoning by means of the appropriate use of branch vents, auxiliary vent pipes, circuit venting, wet venting, or a combination of these methods, in accordance with what is specified in this section.

Main vent pipes and wastewater downspouts must be extended, without reducing their diameter, to connect to a vent extension through the roof, or to a vent collector, so as to provide venting to all parts of the drainage system with air circulation by gravity.

Horizontal vent pipes must have a uniform slope of no less than 1%, such that whatever might condense is carried to the drain.

Vent pipes connected to horizontal sections of the drainage system shall rise vertically or at an angle no less than forty-five degrees (45º) from the horizontal, to a height no less than fifteen centimeters (0.15 m) above the overflow level of the highest sanitary appliance they serve, before beginning their horizontal run. In the event that the height is less than fifteen centimeters (0.15 m) above the overflow level, the installation must be adequate to be able to perform a drainage function.

The discharge into a drainage downspout that is opposite and facing another branch serving one or more toilets must be carried out above the latter, or at a distance of at least twenty centimeters (0.20 m), if the connection is made below the branch serving the toilets.

The connection of the vent pipe must be located above the weir level of the corresponding trap. Except for the vent pipes of the traps of those sanitary fixtures that automatically replenish the corresponding water seals, such as toilets and other similar sanitary fixtures.

In order to prevent unfavorable effects in the drainage systems caused by the pressures produced by soap and detergent foams, in buildings of two or more floors where laundry tubs, washing machines, sinks, and similar fixtures are installed, it is recommended that the drains or branches that receive the liquid waste from such fixtures not be connected in the foam pressure zones indicated below:

a. In the segment of the downspout between its base up to a height of forty (40) times its diameter.

b. In the pipe segment comprised between the base of the stack and a length of ten (10) times the diameter of said pipe, measured along the same.

c. At changes in direction of the wastewater stacks where the sloped portion forms an angle greater than 60º with the vertical, as follows:

c.1 In the stack segment, before the change in direction, forty (40) times the diameter of the stack upstream of said change.

c.2 In the sloped section of the stack, ten times the diameter of said section, downstream of the change in direction.

c.3 In the sloped section of the stack, forty (40) times the diameter of said section, upstream of the change in direction to the vertical.

When it is not possible to avoid connections of waste pipes and branches in the indicated zones, auxiliary vent pipes must be designed, with a diameter equal to that of the main vent pipe or three-quarters (¾) of the diameter of the pipe where foam pressure occurs, in the event that the diameter of the latter is smaller than that of the main vent pipe, and in no case less than fifty millimeters (0.05 m), installed in accordance with the provisions of this chapter.

8.2 VENT TERMINALS

Vent pipes shall be extended to the outside air, up above the roof of the building, or else they may be connected to a main vent pipe, to a vent header, or to the extension of the corresponding wastewater stack that connects them to the outside air (see figure 8.1).

Vent terminals shall extend vertically through the roofs and shall end at a distance of at least fifteen centimeters (0.15 m) above them, and at a distance of at least thirty centimeters (0.30 m) from any vertical surface.

The end of vent terminals shall be covered with a strainer to prevent the entry of animals and insects.

When vent terminals end on an accessible terrace or one with a specific use, the pipes must be extended to a height above the floor of at least two hundred fifty centimeters (2.50 m), if it is within a radius of three meters (3.0 m) from any point on the terrace.

The openings of vent terminals shall be located at a distance of at least ninety centimeters (0.90 m) above any window, door, or any air intake of the building.

The vent terminal installed adjacent to an existing building of greater height must be such as to avoid nuisance to the occupants of the taller building. In the mentioned case, any extension, element, or work necessary for this shall be at the expense of the owner of the shorter building.

In cases where it is impractical to extend the vent pipe to the roof of the building, the terminal may be made on the side of the building. This pipe must have its vent terminal directed downwards.

8.3 MAIN VENT PIPE

Every wastewater stack receiving the discharge of waste branches from two or more floors requiring individual venting, circuit venting, or venting by means of auxiliary pipes, must be provided with a main vent pipe, with the following characteristics:

a. The main vent pipe shall be installed as straight as possible and without reductions in diameter.

b. The lower end shall connect to the corresponding wastewater stack below the connection of the waste branch of the lowest level (see figure 8.1.b).

c. The upper end shall connect to the corresponding wastewater stack (see figure 8.1.c), at a height not less than fifteen centimeters (0.15 m) above the overflow line of the highest sanitary fixture, or several vent pipes may be connected to a vent header (see figure 8.1.d), from which a single vent pipe will go out to the roof; failing that, it shall be extended to the exterior of the building by means of a vent terminal (see figure 8.1.a).

d. It is permissible to install wet venting (see section 8.5) between the lower end of the vent pipe and the stack, when said pipe receives the discharge of a waste branch, provided this does not come from water closets.

When it is desired to install a vent header to which the extensions of the wastewater stacks or the corresponding main vent pipes are connected, such connections shall be made at the upper end of said pipes and never less than one hundred fifty centimeters (1.50 m) above the top floor of the building served by them. The vent header shall extend up above the roof, complying with the provisions of section 8.2.

8.4 INDIVIDUAL VENTING OF FIXTURES

The traps and water seals of all sanitary fixtures must have individual venting, unless the special methods of venting indicated in the following articles under the headings "wet venting," "stack venting," "circuit venting," and "common venting," may be used, in accordance with the special conditions given for such installations (see figure 8.2.a).

Every sanitary fixture connected to a waste branch downstream of a water closet must be vented individually, with the exception of what is indicated in articles 8.4-3 and 8.4-5.

A common vent may serve as an individual vent for no more than two fixture traps. This common vent must be connected at the junction of the two fixture drains and rise vertically from the connection before running horizontally.

The vent connection shall be installed in such a way that the distance between the water seal and the corresponding vent connection is not less than two diameters of the waste pipe and not greater than that specified in table 8.1. This distance shall be measured along the waste pipe, from the outlet of the water seal to the connection of the vent pipe.

The vent connection for the fixture drain must be above the overflow level of the fixture trap, except in the case of water closet drains and floor-outlet type urinals, and models with similar built-in traps for service sinks.

The vent connection to a horizontal wastewater pipe must be made in the upper half of it.

Individual vents must be at least thirty-two millimeters (0.032 m) in diameter and not less than half the diameter of the drain of the fixture to which they are connected, except in the case where a fixture drain of one hundred millimeters (0.10 m) in diameter is installed for a water closet or similar fixture, where an individual vent of thirty-eight millimeters (0.038 m) in diameter may be installed.

8.5 WET VENTING

In a group of sanitary fixtures installed on the same floor, the use of the waste pipe into which up to two (2) elevated sanitary fixtures discharge, for example lavatories, sinks, service sinks, or others, whose total number of fixture units is not more than four (4), is permitted as a wet vent pipe for one or more traps of the other sanitary fixtures of the group, provided it meets the following requirements:

a. The diameter of the wet vent pipe shall be at least fifty millimeters (0.05 m).

b. The total fixture units (u.d.) of the fixtures constituting the group must not be more than fourteen (14).

c. The installation of more than one water closet in the group may not be planned.

d. The length of the waste pipes of each fixture, up to its connection with the wet vent pipe, shall not exceed that required in table 7.9.

e. The main vent pipe, to which the vent pipes and branches of the fixtures whose discharge serves as wet venting are connected, shall be sized as a function of the total number of fixture units of the sanitary fixtures constituting the group.

In case of using a wet vent to vent the drain of a water closet, the horizontal drain branch must connect to the waste stack at a level equal to or below that of the water closet drain. It is also permitted that the wet vent branch connects to the upper half of the horizontal portion of the water closet drain, at an angle not greater than forty-five degrees (45°) with the flow direction.

On the top floor of a building, the drain of a lavatory or a kitchen sink may serve as a vent for the traps of bathtubs, showers, and water closets, provided that the following conditions are met:

a. The lavatory or kitchen sink has individual venting.

b. Not more than one fixture unit (1 u.d.) drains through a wet vent of thirty-eight millimeters (0.038 m), or not more than four fixture units (4 u.d.) drain through a wet vent of fifty millimeters (0.050 m).

c. The length between the wet vent and the water seal of the fixtures must comply with the provisions in table 8.1.

d. See illustrative diagram in figure 8.6 a.

On the top floor of a building, the drain of one or more lavatories with individual venting may serve as a wet vent for the traps of one or more bathtubs or showers, under the following conditions:

a. The wet vent pipe and its extension to the vent stack is at least fifty millimeters (0.050 m) in diameter.

b. Each water closet below the top floor is vented individually.

c. The length between the wet vent and the water seal of the fixtures complies with the provisions in table 8.1.

d. The vertical waste pipe performing the function of wet venting has its diameters in accordance with table 8.2.

On floors where the venting of bathroom groups is done by means of wet venting, the venting of water closets installed below the floor (where the bathroom group is located) may be done by connecting the horizontal drain pipe of the water closet to a pipe coming from a wet vent. This connection must be made with a pipe of at least fifty millimeters (0.05 m), and must be connected to the upper half of the water closet drain, at an angle not greater than 45° with respect to the flow direction (see figure 8.6 b).

8.6 STACK VENTING

Where a fixture discharges directly into a wastewater stack at a level above all other drain connections to the stack, the stack extension may serve as a vent for the fixture trap, with the following conditions:

a. The connection of the fixture drain to the stack is above the level of the lowest part of the trap, except for water closet drains and floor-outlet type urinals.

b. The distance between the fixture trap and the connection with the stack is in accordance with the distances given in table 8.1.

c. In the case where water closets are vented, this method may be used provided the following requirements are met:

c.1 The stack is at least one hundred millimeters (0.1 m) in diameter.

c.2 The stack must not be fed by more than two water closets.

Where two fixtures placed at the same level discharge directly into a wastewater stack at a level above all other drain connections to the stack, the traps of both fixtures may be vented by the stack extension, with the following conditions:

a. The wastewater stack has a diameter greater than the drain of the highest fixture and not less than the drain of the lower fixture.

b. Both drains have their traps within the distances stipulated in table 8.1.

Except as provided in articles 8.6-1 and 8.6-2, a bathroom group (water closet, lavatory, and shower) and a kitchen sink, all on the same floor, may be installed without individual venting for the traps of these fixtures, when it is a single-story building or on the top floor of a building, with the following conditions:

a. Each fixture drain has an independent connection to the wastewater stack.

b. The drains of the water closet and the bathtub or shower connect to the stack at the same level.

c. The distances stipulated in table 8.1 are met.

Note: In this case the extension of the wastewater stack functions as venting.

8.7 CIRCUIT VENTING

When a horizontal waste branch of uniform diameter serves as a drain for a number of sanitary fixtures (see figure 8.2b), not more than eight (8), placed in back-to-back alignment, circuit venting may be used, which consists of the following:

a. When it is the top floor or only floor of the building, the vent pipe shall start at the drain between the penultimate and last fixture, counting from the waste stack, and shall connect to the main vent pipe.

b. On lower floors, the vent pipe shall be complemented with an auxiliary vent pipe connected to the waste branch between the stack and the first sanitary fixture.

c. Lavatories or similar fixtures may be connected in a circuit or loop, with the condition that the traps of such fixtures are protected by individual vents.

Circuit or loop vent pipes shall have at least half the diameter of the horizontal wastewater branch to which they are connected and in no case less than thirty- eight millimeters (0.038 m).

8.8 RELIEF VENTS

In tall buildings, the main vent pipe must be connected to the wastewater stack with auxiliary vent pipes at least once every ten floors, counting from the top floor downwards.

The diameter of the auxiliary vent pipe shall be equal to that of the main vent pipe, and shall never be less than that of the wastewater stack.

The connections of the auxiliary vent pipe to the wastewater stack shall be made with Y-type fittings at a point below the horizontal branch coming from the corresponding floor. The connection to the main vent pipe shall be made by means of a Y-type fitting not less than one meter (1.0 m) above the floor level corresponding (see figure 8.7).

When a wastewater stack has a change in direction of more than forty-five degrees (45°) from the vertical, it will be necessary to vent the sections of the stack that remain above or below said change. These sections may be vented by means of auxiliary vent pipes, one for the upper section immediately before the change and another for the lower section. When the change in direction of the stack is less than forty-five degrees (45°) from the vertical, auxiliary venting will not be necessary.

8.9 SINGLE-STACK VENTING

The wastewater stack may be used as the sole vent pipe, known as the single-stack waste system (see figures 8.2c, 8.4, and 8.5), if the following conditions are met:

a. The sanitary fixtures must be close to each other and each waste branch shall be connected individually and directly to the stack.

b. The sanitary fixtures must have traps with a water seal of seventy-five millimeters (0.075 m), with the exception of the water closet whose seal may be fifty millimeters (0.05 m).

c. The discharge into a wastewater stack that is opposite that of another branch serving one or more water closets must be above the latter, or at a distance of at least twenty centimeters (0.20 m) if the connection is made below the branch serving the water closets.

d. The maximum lengths, diameters, and slopes of the drains of the sanitary fixtures shall be given according to tables 8.3 and 8.5.

e. The stack must be joined to the horizontal waste pipe by means of long-radius elbows. The distance between the connection of the last sanitary fixture and the horizontal waste pipe (at the base of the stack) must not be less than:

e.1 Forty-five centimeters (0.45 m) for buildings up to three floors.

e.2 Seventy-five centimeters (0.75 m) for buildings up to five floors.

e.3 Three meters (3.0 m) for buildings of more than five floors.

f. The waste stack must be extended as a vent extension, as stipulated in section 8.2.

g. Auxiliary vents shall be provided in accordance with the stipulations of section 8.8.

Notes:

. The length of the branch is measured from the trap to the connection with the stack.

. r.p.: main branch; r.d.: discharge branch . The radii of curvature in the last column are referred to the centerline of the fixture.

Notes:

1. Additional vent stacks shall have a connection with the wastewater stack every two floors.

2. Each group of sanitary fixtures consists of a water closet, a shower, a lavatory, a kitchen sink, and a laundry sink.

8.10 SIZING ASPECTS OF THE VENTING SYSTEM 8.10.1 VENT BRANCHES

Branches that connect more than one individual vent to a vent stack or a vertical vent shall conform to the values indicated in table 8.6. When determining the size of that pipe, the column titled Wastewater Stack Diameter must be disregarded and the diameter must be based on the number of fixture units connected to the vent pipe and on its developed length. This length is measured from the connection of the vent branch with the main vent stack to the drain connection of the most remote fixture served.

Notes:

. This table refers to nominal diameters . n.p.= diameter not permitted . u.d.= fixture units 8.10.2 VENTS FOR SUMP PITS AND WASTEWATER RECEIVING TANKS

The diameters of the vent pipes for sump pits and wastewater receiving tanks of buildings must be sized as vent branches.

8.10.3 VENT HEADERS

The sections of a vent header and its vent extension through the roof must be in accordance with table 8.6. When determining the size of that pipe, the column titled wastewater stack diameter must be disregarded and the diameter must be based on the sum of the fixture units of the sections vented with that section of the header. The developed length is that of the vent stack with the greatest total length to the free air.

8.10.4 VENT STACKS

The size of the vent stacks is determined according to table 8.6, based on the size of the wastewater stacks served by them, on the fixture units of these stacks, and on the developed length of the vent stack. Such total length must be measured from the lowest connection of the vent stack to the wastewater stack, to the vent terminal to the free air.

9. STANDARDS FOR RAINWATER COLLECTION AND EVACUATION SYSTEMS 9.1 GENERAL STANDARDS

Rainwater from roofs, flat roofs, and paved or impermeable areas of buildings must be conveyed to public rainwater collection systems using a collection system independent of the wastewater system. The exception is when rainwater from a single-family dwelling may be discharged into the public street, only when it does not cause inconvenience to other neighbors or cause contamination.

Discharging rainwater into the public sanitary sewer network or the building's wastewater evacuation network is not permitted.

When separate sanitary and storm drain systems exist on the same property, they may be located together in the same trench.

For rainwater collection and evacuation systems, it is recommended to perform low-impact designs, which aim to increase the time of entry to stormwater systems, in order to decrease the flow rates within them. Some ways to achieve this are by using bioretention facilities, storing rainwater in floodable areas such as plazas, parks, perimeter parks, and intermittent lakes, among others.

9.2 MATERIALS FOR STORM DRAIN PIPES AND FITTINGS

In rainwater drain pipes located inside buildings, ductile iron, polyvinyl chloride (PVC) pipes, or other materials resistant to corrosion must be used, with prior approval from the health authority. Rainwater downspouts installed exterior to the walls may be ductile iron or galvanized iron sheets. PVC pipes may be used provided they are not directly exposed to sunlight, and may be protected with paint.

The gutters or collection channels of the roofs and flat roofs within the building area may be of galvanized iron sheets, PVC, or other materials suitable for that purpose.

The use of concrete pipes is permitted only for the construction of buried collectors located outside the building area and set back from the foundation of the building structure.

The use of concrete or masonry channels is permitted in the exterior patios and gardens of the building.

The pipes and fittings for rainwater drainage must comply with the standards stipulated in section 7.2.

9.3 STANDARDS FOR THE CALCULATION OF STORM DRAIN PIPES

For the determination of the design flow rates of rainwater drainage systems in buildings, the use of the rational method is recommended:

For the determination of the previous parameters, the values given below are recommended.

a. Runoff coefficient. For the estimation of the runoff coefficient, the values indicated in table 9.1 are recommended; nevertheless, the professional responsible for the design may use other values accepted by good professional practice. The values indicated in table 9.1 correspond to return periods equal to or less than ten years. Less frequent storms with higher intensities require the modification of the runoff coefficient because infiltration and other losses have a proportionally lesser effect on runoff. The adjustment of the runoff coefficient for larger storms can be done by multiplying the value of C by the frequency factor value Cf indicated in table 9.2. The product of C×Cf must not exceed unity.

b. Rainfall intensity. The rainfall intensity is a function of the frequency or return period of the design storm or downpour and of its duration. In the critical case, the rainfall duration is taken as equal to the time of concentration of the tributary area. The intensity of the precipitation shall be estimated from the intensity-duration-frequency curve (IDF curve) corresponding to the meteorological station that the professional responsible for the design of the storm drain system, through the corresponding hydrological study, considers representative for the project area. In case the IDF curves of the station are not available, the values indicated in tables 9.3 and 9.4 may be used.

a. Return period. The frequency or return period of the design downpour shall be determined according to the damages, losses, or nuisances that periodic flooding may cause to the occupants of the building. It is recommended to use a minimum return period of 10 years.

b. Time of concentration. In general, in small urbanized areas (less than 1 Ha) the time of concentration is small and, for practical purposes, can be assumed to be less than five minutes. Consequently, in these small urbanized areas the time of concentration can be considered equal to five minutes. For larger areas, the following formulas can be used:

For an inclined plane:

For the determination of the diameters of horizontal rainwater drain pipes and gutters, the indications of section 7.3.3 shall be followed. It will be accepted in this case that for the design flow the discharge fills a maximum of 3/4 of the height of the collector or drain channel.

For the determination of the diameters of rainwater downspouts, table 9.6 shall be used. As a practical rule, one square centimeter of cross-sectional area of the downspout per square meter of roof area can be used.

Notes:

1. For non-circular downspouts, an equivalent area can be used.

2. Flow rates estimated assuming control at the downspout inlet, and without obstructions.

9.4 CONSTRUCTION REQUIREMENTS

In the construction of rainwater systems, the specifications set for wastewater pipes in section 7.4 and the following articles must be met.

It is recommended that storm drains, cleanouts, and other rainwater receptors be provided with a sand trap when they are located in patios or terraces.

Storm drains and rainwater receptors shall be provided with protective gratings against the dragging of leaves, papers, garbage, and similar materials. The total free area of the gratings shall be at least twice the area of the drain hole.

In those cases where rainwater collectors cannot discharge by gravity, a collecting tank and a pumping system must be provided for its automatic discharge.

In the case of using a rainwater collecting tank, its volume shall be chosen so that it is capable of storing at a minimum the runoff produced by precipitation for an event with a return period of 10 years and a duration of 30 minutes. The volume shall be estimated using the following expression:

Rainwater collecting tanks shall comply with the stipulations of section 7.9.

The design flow of the pumping system shall be at a minimum (2/3)*Q(10,30), where Q(10,30) is the maximum flow produced by a downpour with a return period of 10 years and a duration of 30 minutes.

Rainwater pumps shall comply with the stipulations of section 7.9.

9.5 CLEANOUTS AND CATCH BASINS

Rainwater drainage systems shall be provided with cleanouts and catch basins in accordance with what is established for wastewater drainage systems in section 7.6. The covers of the catch basins may be of metal grating.

9.6 INSPECTION AND TESTING OF RAINWATER DRAINAGE SYSTEMS

Rainwater drainage systems shall be inspected and subjected to the tests specified in section 7.10 for wastewater drainage systems.

9.7 RAINWATER RETENTION AND DETENTION SYSTEMS

Rainwater detention and retention systems are one of the means used to manage runoff discharges from a building as well as to minimize the degradation of the environmental conditions of the receiving water body. In their design, the responsible professional must employ good professional hydrological and hydraulic practices as well as the most appropriate design techniques and procedures. The collection tanks referred to in section 9.4 may not be considered as retention or detention systems unless they are sized following the provisions in this section.

Detention systems or detention basins are characterized by temporarily storing runoff and discharging it in a measured way to a receiving water body or to a storm sewer; however, this discharge is carried out by means of an outlet structure that generally has no control. Commonly, detention basins are kept empty when they are not operating, and their storage volume floods when the precipitation event occurs; upon the conclusion of this event, its emptying occurs through the outlet structure. For this reason, they are sometimes called dry detention basins.

Retention systems or wet ponds store water for a prolonged period. These ponds maintain water permanently and have an additional volume for storing volumes from floods, which is why they are also known as wet ponds. They may or may not have an outlet structure to provide some type of special regulation.

For the design of detention or retention systems, the corresponding administrative authority may define one of the following three criteria:

• a)Setting a minimum storage volume and a permissible discharge flow value in accordance with the project area, land use, or the change in impervious area b) Specifying a permissible discharge flow value for the selected design storm without setting a minimum storage volume c) Establishing the requirement not to exceed the peak flows produced by the existing condition before development, for a specific range of design storm frequencies The first two conditions are generally adopted by the administrative authority following the development of a regional flood control strategy, a basin drainage master plan, or a basin stormwater management plan. The third criterion is generally adopted in the absence of such a strategy or plan. The minimum return period for the design storm for detention or retention systems shall be 10 years.

The use of detention or retention systems has associated potential problems. Among these potential problems, the following can be listed:

• a)The creation of coincident flood peaks that could cause flooding problems in the downstream reaches of the receiving body.
• b)Cumulative increases in downstream flows from several systems as a result of the superposition of the descending limbs of various outlet hydrographs.
• c)Increased potential for accelerated erosion of the water body in the reach downstream of the detention or retention systems.
• d)Extended periods of flooding in the pond area, especially during more frequent events.
• e)Potential intrusion of salts in shallow excavated ponds.
• f)Accumulation of trash and sediments, obstruction of their drains, as well as the occurrence of breeding grounds for mosquitoes or other insects, and other types of undesirable situations.
• g)Risks associated with the flood area of the retention or detention system and with the outlet structure.

Many of these problems can be avoided through detailed basin planning, frequent system maintenance, and proper demarcation of the flood zone, among other measures.

Under no circumstances shall the use of a detention or retention system cause an unacceptable increase in flood levels, whether upstream or downstream of the system. An unacceptable increase in flooding includes any change in the flood characteristics on surrounding properties that could cause damage, or impair the value of the property or the potential land use, or cause problems derived from changes in flow velocity or flow distribution within that land.

The preliminary sizing of the detention or retention system shall be carried out in order to determine the order of magnitude of the required storage capacity.

The initial useful volume of the system (Vs) can be obtained by comparing at least the following estimation procedures:

The final sizing of the detention or retention system shall be carried out by routing the flood hydrograph through the reservoir. The use of computer models to perform this routing is recommended. Regardless of the solution technique used, it must be capable of simulating in detail the hydraulic behavior of the outlet structures, especially when the discharge conduit flows partially full or when submergence conditions occur in the discharge conduit.

The design of the system and its outlet structures must be based on a range of storm durations and appropriate temporal distributions in order to identify the critical hydraulic dimensions. It is not sufficient to simply determine the storm duration that produces the highest peak flow in the drainage area. Although a storm with a longer duration than the critical storm duration for the drainage area produces a lower peak flow, it could require a larger storage volume to prevent an increase in the peak flow from that storm.

Detention or retention systems shall have a principal outlet structure, which will regulate the effluent flow to the receiving body or the storm sewer.

Generally, this structure will be a simple orifice or a pipe, although other types of structures are permitted. However, in any case, the intake area of the structure must be protected against blockage by debris and designed to minimize the risk to a person trapped against said structure. The level of protection will depend on the consequences caused by failure due to intake obstruction and the potential frequency at which such obstruction may occur. The total obstruction of the principal outlet structure must also be considered.

Detention or retention systems shall also have an auxiliary or emergency outlet structure which shall have sufficient capacity to evacuate the maximum flow entering the system. The discharge through this structure to the receiving body or the storm sewer must be done safely. This structure shall have free flow (uncontrolled), and examples of it are broad-crested and sharp-crested weirs, spillways, or overflows, among others.

The design of detention and retention systems shall minimize safety risks to the public and users of the surrounding infrastructure. The use of perimeter fences or meshes around the systems should be considered as a last resort.

Preferably, side slopes of 1 in 6 (1V:6H) or flatter should be used to allow easy exit from the wetted surface. Areas with slopes greater than 1 in 4 (1V:4H) will require ladders and handrails to assist in exit. These recommendations apply especially to systems that incorporate dual-use activities such as active or passive recreation.

Depth indicators must be installed inside the reservoir when the storage depth is greater than one meter (1.0 m). The indicator must have its zero level referenced to the lowest point of the reservoir.

10. INDIVIDUAL SYSTEMS FOR THE TREATMENT OF DOMESTIC OR ORDINARY WASTEWATER 10.1 GENERAL ASPECTS

Systems for the individual treatment of domestic wastewater shall be considered those technical sanitary solutions to be located on a single lot and for the benefit of a single building, discharging ordinary-type wastewater. These individual treatment systems or alternative technology systems may be constituted by several units (placed in series) to improve contaminant removal and increase the efficiency of the treatment (depuración) process. Ordinary wastewater may receive separate treatment prior to its disposal. The water from toilets may be treated and discharged by one line, and greywater or soapy water may be treated and discharged by another line. However, all ordinary wastewater must receive treatment before its final disposal in nature.

For the traditional and alternative treatment systems to be used, it is necessary to establish the basic typologies that will allow the removal of organic loads (BOD, COD) and nutrients (nitrogen and phosphorus compounds), with the purpose of improving water quality before its return to the environment. The minimum parameters that characterize each type of individual treatment system shall seek the best possible water quality before its final discharge (by infiltration or discharge), according to the project conditions, adapting according to its urban or rural location and population density at the site.

Alternative systems for the treatment of excreta and wastewater can be: simple, such as latrines and composting units; separating or not feces from urine, by not using water; and more complex, such as when water in volumes less than one liter or air is used for waste evacuation. In this regard, it is also basic to take into account the possibilities for the final disposal of treated effluents, whether by on-site infiltration or by discharge into permanent watercourses, as well as fecal matter and urine, after correct treatment.

The following techniques for the individual treatment of excreta and wastewater may be considered for use in the country:

a. Dry pit latrines, water-seal latrines, composting latrines, latrines applying vermiculture, or composting units b. Dry toilets or dry or wet urine-diverting toilets, with their corresponding collection and treatment systems.

c. Septic tanks (tanques sépticos) or other simple sedimentation/biodigestion units at sites with infiltration capacity.

d. Improved septic tanks (tanques sépticos mejorados) (that is, the tank working with other additional units or techniques placed in series) or other improved simple units for sites with deficient infiltration capacity or a shallow water table; to complement the process for wastewater treatment in a septic tank (tanque séptico), in a second, third, or subsequent stage, it is possible to use, among others, upflow anaerobic filters, trickling filters, bio-gardens (constructed wetlands).

e. Septic tanks (tanques sépticos), other simple units used as interceptor units or for primary treatment at each emitter's site, whose effluents can receive centralized post-treatment prior to discharge.

f. Systems for the treatment of water from toilets, separated from systems for the treatment of soapy water (or greywater).

g. Systems for the treatment of soapy water (greywater), separated from systems for the treatment of water containing excreta.

h. Systems for the collection of treated wastewater in small diameters with water or by vacuum pneumatic means.

i. Those other techniques for individual (in situ) treatment that have technical-scientific backing, preferably with accreditation by a reference standard or recommendation from an international organization, as well as when they have a recent evaluation (less than three years old) and backing from a research center.

j. Systems for the collection, treatment, and disposal of sludge.

The final disposal of treated water shall be done by means of infiltration or by discharge into permanent watercourses. Therefore, it is important to be clear that the quality of the wastewater will improve according to the number of treatment steps applied to it. Consequently, according to the qualities of the discharge points (environmental fragility) and treatment steps, the following possibilities can be identified:

a. Removal of organic matter and direct infiltration b. Removal of organic matter and nutrients and direct infiltration c. Removal of contaminants, infiltration, and evacuation of excess water to receiving water bodies due to oversaturation or non-infiltration in the same terrain (however, compliance shall be required with the stipulations in the current Reglamento de Vertido y Reuso de aguas residuales).

d. Removal of contaminants and direct discharge to water bodies, including via lines parallel to existing sewers (compliance shall be required with the stipulations in the current Reglamento de Vertido y Reuso de aguas residuales).

e. Removal of contaminants, exposure of effluents to evapotranspiration, and use in irrigation (compliance must be made with the stipulations in the current Reglamento de Vertido y Reuso de aguas residuales).

The setback of the units for the individual treatment of wastewater and the elements required for infiltration that are located on the land of a dwelling or building shall be at least one meter (1.0 m) from the property boundaries. These units and elements must also be located at safe distances so as not to endanger structural aspects of walls or fences, neighboring infrastructure, or the geotechnical stability of the land.

10.2 USE OF THE SEPTIC TANK TECHNIQUE: DRAINAGE, THE TANK, AND SLUDGE MANAGEMENT

These standards propose to set basic parameters for the correct functioning of the sanitary technique of septic tanks (tanques sépticos) when used for the treatment of domestic wastewater. This technique is highlighted because it is the most used in the country; however, it is emphasized that there are other sanitary techniques for the individual treatment of excreta and wastewater. Emphasis is placed on characteristics to be met for the drainage, the sizing and maintenance of the tank, and the importance of providing additional treatment for septic sludge (lodos sépticos) or fecal material to be extracted periodically.

The septic tank (tanque séptico) is an anaerobic system for the individual treatment of waste that uses the soil's capacity to absorb, under traditional and basic conditions of the technique, because this technique, depending on the circumstances, can improve its functioning when complemented with other sanitary units or techniques. Therefore, proper functioning depends on the sedimentation/biodigestion tank appropriately retaining the heaviest solids and the fats that travel with the liquids, as well as on the land where these treatment systems are placed having the capacity to allow all the water processed with this sanitary technique to infiltrate into it.

Periodically, a partial removal of accumulated fats and sludge must be carried out. The removed sludge (lodos) or fecal matter requires additional treatment for its complete stabilization so as not to negatively affect the environment.

Every wastewater treatment process aims to remove contaminant elements and transform some of them into simpler components. Individual treatment systems remove things from the water, but do not vary the quantity of it.

Gases are produced, and residues known as mineralized sludge (lodos mineralizados) are obtained. The principle that matter is not destroyed, but rather transformed, is respected and recognized. It is also established that whatever the volume of water entering the sedimentation/biodigestion tank, it will be that same volume of water that must subsequently be accounted for proper discharge.

All water used and discharged as wastewater must receive treatment before its reincorporation into nature. It is fundamental to be clear about the appropriate assessment of the volume and types of wastewater to be placed in the treatment system, according to the discharge made per day, for example:

a. The volume and type of all used water of domestic origin, according to the user population in a building: toilets, sinks, showers, kitchen sinks, washbasins, or laundries.

b. The determination of that ordinary wastewater volume can be done following the criteria for water supply allocation (dotación) and determination of average return flows. A value of 82% of the assumed average allocation (dotación) is recommended for this return factor. However, the professional responsible for the design may use another value as long as it is in accordance with good professional practices.

c. Allocation (dotación) data can be reassessed when information is available that typifies the consumption of a specific community and when low water consumption fixtures are placed in the work and families have defined water-saving principles.

However, due to this concept of qualities and quantities, it is necessary to adapt the application of the individual system for wastewater treatment when using the septic tank (tanque séptico) technique or any other, when for cultural reasons or modern society customs, domestic activities are defined that discharge extraordinary volumes of wastewater in very short periods. These types of discharges alter the contents of the tanks, "wash out" the biological system, and disturb the settled or suspended matter, consequently reducing the system's efficiency for contaminant removal.

Some of these extraordinary activities are the concentrated washing of clothes on only one or two days of the week, as well as the discharge of water from a bathtub. For these cases, it is advisable to separately treat water containing excreta and separately treat all other wastewater (greywater) that is evacuated.

Basic elements of this individual treatment technique:

a. Absorption capacity of the soil.

b. Sufficient separation between the bottom of the discharge points in the subsoil and the groundwater table levels.

c. The tank is a sedimentation unit and at the same time an anaerobic biodigester.

d. The storage volume of the tank must correspond to the number of users the system has and the daily volumes of water used by them.

e. The need to perform periodic removal of fats and sludge (lodos).

f. The existence of systems for the removal, transport, treatment, and proper disposal of septic sludge (lodos sépticos).

Infiltration tests are a basic requirement to determine the acceptability or rejection of the chosen site as the zone where the drainage subsystem will be placed. This subsystem complements the process for the treatment of ordinary wastewater, carried out individually. The drainage or disposal site by infiltration of treated wastewater for an individual solution is determined with greater certainty when having the results of the infiltration test performed directly in the space and at the depth, in the land where the drainage will be located.

This test must consider the following:

a. Direct measurements or readings at the site and in the strata where the intended infiltration system will be placed.

b. Full saturation conditions to determine the actual infiltration rates of the treated water in that terrain. These systems must function correctly in rainy seasons and periods of high soil saturation.

c. The number of holes to execute an infiltration test is defined according to the importance of the project and the size of the land. One criterion is the location of test holes, defining an influence radius of thirty meters (30 m) for each one, a criterion traditionally proposed to separate the location of a drainage zone and a well for water supply.

Conditions for executing the test. It is essential that the field work be carried out in two stages, namely:

a. Opening, preparation of the test hole(s), and saturation of the soil for 24 hours. Actions to be carried out on a first workday.

b. Readings or collection of field data, for each test hole, on a second workday and after a saturation period initiated 24 hours prior. These readings shall be taken at 30-minute intervals for four hours. If the soil has a high percolation rate, the time interval between readings is reduced.

For this, the data from the last period of readings obtained with the infiltration test is used (an average of the data obtained per test hole is not taken). The infiltration rate is obtained by dividing the time interval used between readings by the last height difference determined. The definition of an initial characterization by its percolation capacity for the land for a project with several dwellings or buildings, where several infiltration tests have been performed, shall be done by averaging the infiltration rates obtained for each of the test holes.

A basic complement to this test is the carrying out of explorations at greater depth, in the same hole where the infiltration test is performed, for the purpose of verifying the existence or not of groundwater. Groundwater levels in an infiltration field must be located at least 2.0 m below the bottom that the drainage trenches or absorption wells will have.

The drainage can be infiltration beds formed by trenches and distributed over wide areas of the land, or more concentrated, defined by infiltration wells.

The drainage is calculated by establishing a hydraulic relationship between the infiltration rate that characterizes the land under study (determined by the infiltration test) and the flow or water discharge to be produced by the users of the technique used for wastewater treatment.

The calculation of the drainage is the definition of the length and cross-section of trenches, or the depth and diameter of absorption wells. Annex B to this regulation presents a procedure for executing the calculation of said dimensions (cross-section, length of trenches).

In an infiltration system composed of trenches or surface drainage, biodegradation phenomena also occur (given the adherence of microorganisms on the walls of the filter material) and evapotranspiration due to the effect of solar radiation and plants that may grow in the vicinity. Therefore, the following points must be considered:

a. Drainage trenches must be filled, from the duct or pipe distributing effluents from the tank downward, with stone in sizes between 7 and 10 cm (providing more contact surface and fewer voids than the traditionally used rough or large-sized stone).

b. Plastics or other impermeable materials must not be placed, because the escape of gases and the evapotranspiration that will be obtained from the biological activity to develop and from the solar rays striking that zone must be allowed.

c. Thus, the cross-section of a drainage trench is characterized by the following elements and strata:

c.1 A pipe, preferably smooth on its internal surface, with perforations for the distribution of liquids with dissolved organic matter and percolation downwards.

c.2 Granular material between 7 and 10 cm, below that distribution pipe.

c.3 Granular material in smaller sizes (9 mm and larger), on both sides of the distribution pipe and above it. That other stone is placed in gradual granulometric variation (from larger to smaller, from bottom to top) to prevent saturation or clogging as a consequence of the superficial backfilling done with soil from the site.

d. When ground surfaces are covered (sidewalks, slabs, pavements, pavers) where the trenches are placed, or when absorption wells are used, the advantages of other biodegradation stages that bacteria can perform in the drainage stones and the reductions in water volumes by evapotranspiration will not be utilized.

e. On sloped land, drainage trenches are constructed parallel to the contour lines (following the contour). To achieve the total required length, it may be necessary to use several levels of the land, so that the water will pass by overflow from the trench at the higher level to the trench at the lower level.

The horizontal separation between trenches must be at least five meters (5.0 m).

The dimensions, cross-section, and length of the drainage trenches are defined by the results that determine the infiltration capacity of the land where they are to be placed and the amount of water intended to be infiltrated. Each result of these infiltration tests is specific to each site, therefore extrapolations are very uncertain. It is important to relate the amount of water to be placed in that land to the infiltration rate obtained. The infiltration area then obtained refers to the relationship with the walls and bottom of the trenches. However, that wetted perimeter must be corrected with a reduction factor, given the hydraulic variation caused by the gravity supply and relatively low velocities of the effluent water from the distribution pipe in relation to the trench walls.

It is the space of the land where the infiltration action is allowed. This is the area of influence that at least (minimum) must be assigned around the sides of the trenches or infiltration wells so that the water percolates into the used land, taking into account rain effects and coverings to be placed over this land.

Like infiltration trenches, absorption or infiltration wells are located after the individual systems used for wastewater treatment, to fulfill the same objective of conducting the treated water volumes towards the lower soil strata. These wells are excavations, generally cylindrical, in diameters of one meter or greater and depths of 3 meters or more. The bottom of these wells, as with the previous indications, must be at least 2.0 m above the groundwater levels that may exist at each site. Verification to be performed when the field infiltration tests are executed.

An absorption well is constructed as a deeper excavation, which requires internal elements for water storage and others for water distribution towards the permeable zones of the soil. The general structure of a well may be composed of the following elements:

a. The element for water storage is a self-supporting and internally permeable structure (with openings for the passage of water from the interior towards the soil), which can be built with different materials such as concrete blocks, fired clay bricks, concrete or PVC culverts, among other materials.

b. For the passage of water towards the soil, crushed stone (19 mm) is placed at the bottom (30 cm) and in the space (15 cm) that must be left between the wall of the excavation and the wall of the structure being built.

c. The water to be filtered is discharged into the empty space, at the center of the structure being built, through the lid or upper slab of this unit.

Dimensions for an absorption well. The calculation of the dimensions of an absorption well is also determined from the results of the infiltration test and the volumes of water being processed by a sanitary technique for individual treatment.

To determine the dimensions of an absorption well, it must be clear that the infiltration tests must now be performed in each of the strata, levels, or soil layers that the land has (for example, at every meter of the intended depth), and the value to be used in the calculations will be an average of the final data obtained (infiltration rate for each stratum).

The filtration area considered for determining the dimensions of an absorption well is that formed by the walls of the well, below the level of the liquid inlet pipe. For the determination of that cylindrical area, the bottom or floor of the well is not included, nor the walls above the liquid inlet or in intermediate strata formed by impermeable soils.

If this technique is used for the disposal of treated effluents, each well used must be separated from one another by at least a distance equal to three times their excavation diameter. For wells more than six meters (6 m) deep, the minimum spacing between wells must be six meters. The minimum separation from an absorption well to property boundaries and buildings must be at least three meters (3.0 m).

**Proper functioning of the tank** (removal equal to or greater than 50% of the organic load initially contained in the wastewater) with this sanitation technique must respect basic principles of sedimentation and biodigestion, and therefore the following must be observed:

a. A recommended ratio of 1:3 between the width and the length of the unit to be built or that is prefabricated, for correct sedimentation, ensuring the retention of the majority of solids carried and in suspension.

b. A useful liquid depth between 1.0 m and 2.5 m, for correct sedimentation actions and placement of strata for biodegradation.

c. A hydraulic retention time for sedimentation of not less than 24 hours.

d. A biodigestion retention time not less than that required by the water temperature and applied load.

e. A sludge storage time in accordance with the load and logical cost assessment to define the convenient time between cleanings. This storage space is recommended for at least two years and not more than five years.

Other proportions, shapes, or characteristics of the tanks may function as treatment units for this sanitary technique, but obtaining other efficiencies for the removal of organic load, mainly.

In these tanks, space must be available to define several layers, which from bottom to top are:

a. Zone for the storage of matter, a site for the accumulation of solids or digested sludge b. Biodigestion zone, where the main digestion of solid and dissolved material takes place c. Sedimentation zone, where a large quantity of active bacteria are also located and liquids with dissolved organic matter travel d. Zone for upper greases or scum and the free space required for the gases from the anaerobic process to be located

The sizing of each of the septic tanks, in addition to considering the above principles, must be based on design formulas taking into account the number of users, the quantity and type of water used per day, the temperature of the wastewater, and the appropriate period for the removal of liquid and solid matter. Annex C to this regulation presents a calculation procedure that even takes into account the water temperature prevailing in tropical conditions.

Every septic tank must have flow-regulating elements (baffles) at the inlet and outlet; these elements reduce disturbances to the treatment process and are useful for preventing the exit of greases and sludge to the next stage.

For the simplest conditions of a single-family dwelling, the inlet and outlet elements in a septic tank are achieved by placing T-fittings, extended with pipe nipples, of appropriate length (40% of the liquid depth). In this way, these baffles allow flow in the sedimentation zone of the tank. These same T-fittings must be extended upwards, leaving two centimeters (0.02 m) free before the upper slab or cover. That upper free space will allow the release of gases through the same inlet elements (ducts coming from the building) and outlet (towards the drains).

The tank, due to the anaerobic process that takes place, must be hermetic. The walls and floor of the tank must be impermeable.

The materials used in its construction or manufacture for walls, floor, and cover must resist the attack of acids and sulfates carried by the water or formed during the treatment process. The tanks must be internally coated or painted with appropriate products to prevent chemical attack on the tank material.

The minimum internal width of a concrete or masonry (block) tank is approximately 70 cm. This width barely accommodates the person who will waterproof and apply the insulating protective coatings (bituminous paints or epoxy-based products).

Every tank requires:

a. The placement of two cleanouts in the upper slab or cover, exactly over the position occupied by the liquid inlet and outlet T-fittings. These cleanouts will serve to check the level of stored sludge through them. In concrete tanks, these cleanouts can be 100 mm PVC pieces with threaded plugs.

b. The placement of at least one main cleanout to facilitate matter extraction and cleaning tasks. This cleanout must be made with dimensions not less than 40 cm x 60 cm and must be built with curbs on the slab or cover (to prevent the ingress of surface water) and the curbs with flexible sanitary seal (silicone or bituminous paste) against the cleanout cover itself to prevent the escape of gases. Placing covers with chamfered edges flush with the tank slab or cover is not correct, because these tanks must be hermetic and impermeable and, with this construction style, cracks or gaps form through which gases escape.

c. Maintain a level difference of 7 cm between the bottom of the inlet pipe and the bottom of the outlet pipe, with the outlet pipe being the lowest.

d. Correct and appropriate means to evacuate the gases produced.

The release of gases can be induced by directing them through the upper and open part of the T-fittings towards the ventilation lines corresponding to the pipes that evacuate the building's water. This possibility demands not placing a trap before the tank inlet, since that trap would prevent the release of gases from the tank towards the sewer ventilation line left in the building. It is also possible by directing the gases towards the drainage, through the outlet T-fitting.

Another possibility for evacuating the gases formed in the tank is by means of direct and exclusive vents placed on the tank itself. These direct ventilation lines must exit from the upper part of the interior of the tank and be directed towards a nearby wall, rising to roof height. It is not correct to leave ventilation pipes in an isolated and loose manner on the tank slab or cover.

All systems for the treatment of excreta and wastewater, when transforming matter, will produce sludge as basic material, whether floating, sedimented, or mineralized. In general, it is established that sludge is the solids that have been separated from polluted waters, integrated with quantities of water that now form part of its consistency. Sludge is a watery and semi-liquid mass.

Due to the concentration of bacteria involved in the treatment process, in most cases, sludge is more polluting than the waters that brought it.

In a septic tank, sludge is located in two main sections: some are heavy and deposit at the bottom of the tanks; others, of greasy origin, are light and float as scum on the zones or layers mentioned above. When extracting sludge from a tank, old sludge from the first days of operation is removed, which has already stabilized, and fresh sludge from recent deposition. This is the basic reason (non-uniform degradation of the extracted material) for requiring other stabilization steps.

10.3 OPERATION AND MAINTENANCE OF A SEPTIC TANK

Preventive maintenance must be carried out through periodic inspection of the tanks. This activity must be performed at least once a year.

Verification of the sludge level at the bottom: this will be done through the cleanouts (T-fittings) at the inlet and outlet of the tank. To avoid contamination with greases, a rod with wicks or pieces of cloth tied along the entire part to be submerged is introduced. In this way, by impregnation, it is possible to record and measure the amount of sludge accumulated at the bottom of the tank.

The level is compared to the position of the water outlet mouth in the lower nipple (additional length given downwards) of the outlet T-fitting. The free space between the water outlet and the upper part of the accumulated sludge must not be less than twenty centimeters (0.20 m).

Verification of the thickness of the floating scum layer: in a similar manner, with the help of an instrument such as a piece of wood with an L-shaped end and through the upper cleanouts or inlets, the thickness of the scum layer can be inspected. The depth at which the lower mouth of the outlet T-fitting is located and the depth of the bottom or underside of the scum are measured.

The level is compared to the position of the water outlet mouth in the lower nipple (additional length given downwards) of the outlet T-fitting. The proximity of the scum or free space between its bottom and the water outlet must not be less than five centimeters (0.05 m).

The tanks must be cleaned at the end of the design period (n = number of years planned for matter storage) or as a consequence of a prior inspection indicating the need to carry out such a function early. This is when the scum or sludge is very close to the lower mouth of the outlet T-fitting, since the sludge or scum could be carried towards the drains and these could become clogged.

When the tank is inspected, the depth of the sludge and scum must be measured in the vicinity of the outlet T-fitting. The tank must be cleaned if: a) the bottom of the scum mass is less than 7.5 cm from the lower edge of the T-fitting; or b) the sludge reaches the limits specified in table 10.1.

a. Cleanings should be carried out, preferably, in the dry or non-rainy season of the region where the structure is located. This climate condition is convenient because when passing fecal matter or sludge to other treatment units for quality homogenization or stabilization, one of them is used for the purpose of eliminating the water they contain, and the dry season is more favorable.

b. The sludge or solids deposited at the bottom of the tank and the scum that floats must be extracted.

c. For cleaning tasks, the larger opening located in the cover or upper slab of the tanks will be used.

d. The first step to carry out is to remove the scum. After that, the contents of the tank are mixed to stir its content and then be able to extract old material and fresh material simultaneously.

e. When doing this work, if appropriate pumping equipment is not available, scum, sludge, and liquids can be extracted with buckets that are deposited in larger containers with lids (which could be barrels or other similar items).

f. From a sedimentation/biodigestion tank, only 80% of its content must be extracted, leaving inside it a volume equivalent to 20% of the total; this material is left as a seed of active bacteria, so that the functioning of the treatment system continues, with appropriately adapted biological material.

g. The extracted sludge and liquids require treatment. The process for treating fecal matter from a septic tank or fecal sludge is different from the centralized process for wastewater. This is because in sludge there are other concentrations of matter and its components are different. It is appropriate that centralized treatment sites for urban wastewater have specialized and additional units to treat this other material; if the proper facilities do not exist, the required process must be substituted by alternate treatment stages, such as a further biodegradation step and water removal (sludge in an additional biodigester for no less than four weeks and then in drying beds for the time corresponding to the climatic conditions, mainly precipitation and evaporation of the place).

h. The stabilized domestic sludge generated from ordinary wastewater treatment is valuable as a source of nutrients and as a soil conditioner, so it could be used in agriculture. The use of sludge should be encouraged where possible, provided that proper protection for people's health is ensured.

Disposing of sludge and liquids extracted from a septic tank directly, without prior treatment, into a water body or onto land is prohibited because it is a direct and serious act of contamination.

11 LP GAS INSTALLATIONS 11.1 GENERAL STANDARDS

The gas pipes shall not be subjected to any stress. The gas consumption equipment shall be firmly installed such that they do not transmit any stress to the supply pipe.

Gas installations shall comply with recognized standards, shall be accepted by the administrative authority, be in accordance with the current fire regulations (standard NFPA 54 National Fuel Gas Code and NFPA 58 Liquefied Petroleum Gas Code) and, when applicable, also in accordance with the Reglamento para la regulación del sistema de almacenamiento y comercialización de hidrocarburos.

Gas installations shall not be located in any pit or basement, nor under windows or louvers, under interior stairs, or in rooms housing boilers, heaters, or electrical meters.

Gas installations shall not supply any water heater located in a pit or basement, unless it has adequate ventilation.

Care shall be taken to ensure that the discharge from relief valves occurs in an open and ventilated area. The discharge shall not occur inside or under a building. Furthermore, it shall be at a horizontal distance of at least ninety centimeters (0.9 m) from any opening of a building that is below the discharge level when the container is of the cylinder type, and at least one hundred and fifty centimeters when the container is of the ASME type.

11.2 MATERIALS FOR PIPES AND FITTINGS

. Wrought iron . Steel (black, galvanized, carbon) . Copper (type K and L) . Polyethylene (PE) . Corrugated stainless steel

Used pipe may be used provided it has not been used for any purpose other than transporting gas; in addition, it must be in good condition and free of internal obstructions.

All pipes, valves, and fittings used in gas piping systems shall be designed and certified for use with LP gas.

Valves of a size equal to or less than fifty millimeters (0.05 m) shall be made of brass or another material approved by the administrative authority.

All fittings used shall be made of malleable iron, of the same material as the pipes, or be certified plastic fittings for use in gas.

11.3 PIPE INSTALLATION

All joints made in gas pipes, except in the case where they are welded, shall be threaded, with an approved standard thread type.

Threaded joints, in cases where required, shall be made with an approved sealing material, which must not react in the presence of the fuel gas. This must be placed only on the male thread.

No gas pipe shall be installed in or on the ground, under any building or structure unless it is installed within a hermetic conduit or casing. The terms building and structure refer to balconies and stairs, whether roofed or not, passageways, or corridor-roofs.

The conduit shall be made of a material approved for underground use and its schedule shall be at least 40. The internal diameter of the conduit shall be at least twelve millimeters larger than the diameter of the internal pipe transporting the gas.

The conduit shall extend beyond the point of consumption or its exit from the wall for a distance of at least thirty centimeters (0.30 m) and its terminal shall not be sealed. In the event that the conduit does not exit the wall, it shall be accessible, and the space between the conduit and the gas pipe shall be sealed to prevent gas leaks into the building.

All exposed gas pipes shall be located at a distance of at least fifteen centimeters (0.15 m) above the floor or any structure.

Iron pipes located in exterior sites of buildings shall be adequately protected from corrosion, whether they are buried or exposed to the environment.

All buried metallic pipe shall be covered by a layer of earth, or other protective material, of at least thirty centimeters (0.30 m). In the case of buried plastic pipes, the protection shall be at least forty-five centimeters (0.45 m). Riser pipes shall be metallic and shall be covered or protected for a distance of fifteen centimeters (0.15 m) above the protruding floor level. When a plastic riser connects to a buried metallic horizontal pipe, a portion of the latter shall be raised for a distance of at least sixty-six centimeters before connecting it to the plastic pipe.

All iron pipe that is buried shall be electrically isolated from the rest of the gas system by means of installing isolation fittings. These shall be installed at a distance of at least fifteen centimeters (0.15 m) above floor level.

The protective coatings used on gas pipes shall meet recognized quality standards. Zinc coatings (galvanizing) are not considered adequate for the protection of buried gas pipes. Pipes with protective coatings shall be tested and inspected, and any visible damage, imperfection, or holes must be repaired.

Gas pipes shall be adequately supported on supports, which shall be spaced according to the values shown in table 11.1. Buried gas pipes shall be effectively supported along their entire length. In selecting the support material, the prevention of galvanic corrosion shall be considered.

Gas installations that supply more than one premises or building shall be equipped with shut-off valves according to the number of premises or buildings they supply. These valves shall be located outside the respective building or premises and be in an easily accessible location.

Gas outlets used to supply equipment for grills or fireplaces shall have operating valves installed, which shall be installed in the same room where the equipment is located, away from the heat source, and at a distance not greater than one hundred and twenty centimeters (1.20 m) from the supply pipe terminal. In the event that the discharge pipe of the operating valves is made of galvanized iron, it shall be embedded or covered by a layer of at least five centimeters (0.05 m) of concrete or masonry.

Cut-off valves shall be placed at the equipment consumption points, regardless of the presence of any valve belonging to the appliance. These shall be installed upstream of the union between the gas supply pipe and the equipment pipe.

The cut-off valve shall be located close to the equipment it supplies, must be at a maximum distance of ninety centimeters (0.9 m) from the equipment; in addition, it must be located in the same room where the equipment is located and be easily accessible.

Seismic valves shall be provided in those buildings where their installation is required by the administrative authority. These valves shall be solidly placed at the regulator outlet and fixed to a wall or column. If the valve cannot be fixed to a solid wall or structure, it is recommended to install it in areas without constant vehicle or pedestrian traffic. Seismic valves may not be placed in boxes or cleanouts, nor on sidewalks or in areas with constant vehicle or pedestrian traffic. Seismic valves are devices that automatically cut off the gas supply when an earthquake of sufficient intensity occurs in the area where the building is located.

Changes in direction made in gas pipes shall be made with appropriate fittings, except for PE pipes for gas, which may be bent to a radius of not less than twenty-five times the nominal pipe diameter.

Gas consumption equipment shall be connected to the gas supply pipe by means of appropriate joints or connectors and comply with the following:

a. Metallic equipment connectors shall have a length not exceeding ninety-two centimeters (0.92 m), with the exception of dryers, for which the connector may have a maximum length of one hundred and eighty centimeters (1.80 m).

b. Equipment connectors shall not be concealed or extend through any wall, floor, or the appliance's combustion chamber.

c. An accessible valve for the equipment shall be installed upstream of the connector, which must have a diameter greater than or equal to the equipment connector.

d. Connectors shall be of an adequate size to satisfy the total demand of the connected equipment, for which tables 11.2 and 11.3 may be used.

e. Connectors manufactured with aluminum alloys may only be used in interior spaces and out of contact with any masonry, insulation, or plastering.

f. Connecting equipment located inside a building using any type of gas hose is prohibited, with the exception of equipment that requires mobility during its operation. When gas hoses are used, they shall have a maximum length of one hundred and eighty centimeters (1.8 m). Gas hoses, only in cases of special equipment, shall not extend from one room to another, nor go through walls, ceilings, or floors. Gas hoses shall not be used in cases where they could be exposed to excessive temperature (greater than 50 ºC) and shall never be used as a substitute for the standard equipment connector.

g. Connections of gas equipment may be made by means of quick-disconnect devices.

Notes: 1. The capacities shown are valid for pressures greater than or equal to 0.203 mca. 2. Flexible connectors are indicated by their nominal internal diameter. 3. Semi-rigid connectors are indicated by their external diameter. 4. The capacities shown are based on the use of fittings and valves supplied with the equipment connector.

Notes: 1. The capacities shown are valid for pressures less than 0.203 mca. 2. Flexible connectors are indicated by their nominal internal diameter. 3. Semi-rigid connectors are indicated by their external diameter. 4. The capacities shown are based on the use of fittings and valves supplied with the equipment connector.

Regulators shall be installed in locations where they are accessible for inspection and maintenance; in addition, they must be in locations with good ventilation. Appliance pressure regulators that require access to the atmosphere for proper operation must be equipped with a vent pipe leading to the exterior or, if the regulator vent is an integral part of the appliance, inside the combustion chamber adjacent to the continuous pilot, unless it is constructed or equipped with a vent-limiting means to reduce the escape of gas from the gas vent orifice in case of diaphragm failure.

The location and installation of fixed containers in buildings shall comply with the provisions of the current national regulations issued by the administrative authority.

Additionally, they must comply with the distances indicated in the NFPA 58 Liquefied Petroleum Gas Code standard.

11.4 PIPE SIZING

Piping systems shall be sized and installed to supply sufficient gas to meet the maximum demand of all equipment using it. The diameter of the gas pipe shall be in accordance with good Engineering and Architecture practices.

Gas installations may have one or two regulation stages, the first stage being called high pressure and the second stage low pressure.

The maximum pressure at which any pipe of a gas system located inside a building may operate shall not be greater than 34 kPa (or 5 PSI) unless it meets one or more of the following conditions:

a. The piping system is welded. b. The pipe is in a ventilated channel or otherwise protected against accidental gas accumulation. c. The pipe is inside a building or in an area separate from a building intended exclusively for industrial or heating processes, research, storage, boiler rooms, or mechanical equipment rooms. d. The pipe supplies gas to appliances or equipment used for agricultural purposes. e. The pipe is an LP gas system with an operating pressure greater than 138 kPa (20 psi) and complies with the provisions of the NFPA 58 Liquefied Petroleum Gas Code standard.

The hourly gas capacity required at each supply outlet shall not be less than the maximum value specified by the manufacturer of the equipment to be connected at that outlet.

In cases where the capacity of the equipment to be installed is not specified, the data in table 11.4 may be used as a reference.

The diameter of the supply outlet pipe for any equipment shall be at least twelve millimeters (0.012 m).

11.5 INSPECTION AND TESTING OF GAS INSTALLATIONS

Gas supply installations shall be inspected and tested before they enter service in order to determine whether the materials, design, fabrication, and installation meet the requirements of this code. The inspection shall consist of a detailed visual review during or after manufacture, fabrication, assembly, or pressure tests, as appropriate.

To verify compliance with the approved project, the professional responsible for the work shall inspect it regularly, according to the stipulations established in the CFIA regulations, demanding corrections in cases of alteration as an indispensable requirement for approving the work.

The professional responsible for the work is obligated to test the system as a guarantee of its good execution and design, according to the pressure test described below:

a. A piping system may be tested as a complete unit or in sections. The pipes to be tested shall be free of foreign materials and debris.

b. All pipe connections, including welded ones, shall be exposed during the test. Excepted are those joints or pipe ends that are covered or hidden and that have already been tested in accordance with this Code.

c. The test gases to be used include: air, nitrogen, carbon dioxide, or an inert gas. Oxygen shall never be used.

d. The closure of all cut-off valves shall be verified. Under no circumstances may a valve on a line be used as a barrier between the gas in one section of the pipe and the test gas in the adjacent section, unless two valves are installed in series with a pressure-indicating valve placed between them. A valve shall not be subjected to the test pressure unless it can be determined that the valve, including its closing mechanism, is designed to safely withstand the pressure.

e. Where the pipe is connected to appliances, equipment, or equipment components designed for operating pressures less than or equal to the test pressure, these devices shall be disconnected and the pipe outlets plugged. If the operating pressure of the devices is greater than the test pressure, the devices shall be isolated from the pipe by closing the respective shut-off valve.

f. The test pressure shall be measured with a pressure gauge or other pressure-measuring device designed to read, record, or indicate pressure losses due to leaks during the test period. The pressure source shall be isolated before the test period begins. Mechanical pressure-measuring devices shall have a pressure range such that the maximum scale value is not greater than five times the test pressure.

g. The test pressure to be used shall not be less than 1.5 times the proposed maximum working pressure, but not less than 20 kPa (3 PSI), regardless of the design pressure. When the design pressure is greater than 862 kPa (20 PSI), the test pressure shall not be greater than a value that produces a hoop stress in the pipe greater than 50% of the pipe's yield strength.

h. The test duration shall not be less than 30 minutes for each 14 m³ (500 ft³) of pipe volume or fraction thereof. When testing a system having a volume of less than 0.28 m³ (10 ft³) of pipe volume or a system in a single-family dwelling, the test duration shall be a minimum of 10 minutes. The test duration is not required to exceed 24 hours.

i. The piping system shall withstand the specified test pressure without showing any evidence of leaks or other defects. Any reduction in test pressure indicated by the pressure gauges shall be considered an indication of the existence of a leak. Where a leak or other defect is located, the affected portion of the pipe shall be repaired or replaced and the pressure test repeated.

When repairs or additions are made after the pressure test has been performed, the affected pipe shall be tested again. In the case of minor repairs or additions, it is not mandatory for these to be tested by pressure tests, provided that the work is inspected by a responsible professional and the connections are tested with a non-corrosive leak-detection fluid or another leak-detection method approved by the administrative authority.

In specific or special cases, the administrative authority may subject the installations to any additional tests it deems pertinent.

12. BIBLIOGRAPHY ACOSTA, G. and AZEVEDO, J.M. Manual de Hidráulica, Ed. Harla, 1976.

ASSOCIAÇÃO BRASILEIRA DE NORMAS TÉCNICAS. Instalaçoes Prediais de Agua Fria, Norma Brasileira NB 92, 1968.

ASSOCIAÇÃO BRASILEIRA DE NORMAS TÉCNICAS. Instalaçoes Prediais de Agua Quente, Norma Brasileira NB 128, ABNT, 1968.

ASSOCIAÇÃO BRASILEIRA DE NORMAS TÉCNICAS. Instalaçoes Prediais de Esgotos Sanitarios, Norma Brasileira NB 19, ABNT, 1950.

BOVAY, H. E. Handbook of Mechanical and Electrical System for Buildings. McGraw Hill. 1981.

BRIGAUX, G., and GARRIGOU, M. Fontanería e Instalaciones Sanitarias. 3rd ed. Barcelona, Ed. Gustavo Gili, 1976.

BUILDING RESEARCH STATION. Sanitary pipework: Part 2. Design of pipework. Building Research Establishment Digest No. 249, England, May, 1981.

COLEGIO DE INGENIEROS DEL PERÚ. Reglamento Nacional de Construcciones, Instalaciones Sanitarias, 1973.

COLEGIO FEDERADO DE INGENIEROS Y DE ARQUITECTOS DE COSTA RICA. Código Sísmico de Costa Rica. Cartago, Ed. Tecnológica de C.R., 2002.

COMISIÓN DE SERVICIOS PÚBLICOS. Reglamento Política de Control de Grasas. Gobierno de la Ciudad de Winston-Salem, Carolina del Norte. USA, 2003.

DEPARTAMENTO DE SALUD PÚBLICA DE ILLINOIS. Illinois Plumbing Code. 2004.

FLORIDA DEPARTMENT OF COMMUNITY AFFAIRS. The Florida Building Code: Fuel Gas Volume. USA, 2001.

FLORIDA DEPARTMENT OF COMMUNITY AFFAIRS. The Florida Building Code: Plumbing Volume. USA, 2001.

ILHA Sangoi de Oliveira, Marina and MARACCINI G, Orestes. Sistemas Prediais de Agua Fria. Texto Técnico- Serie TT/PCC. Departamento de Ingeniería Civil, Universidad de Sao Paulo. Ed: EPUSP, 1994. P. 113.

ILHA Sangoi de Oliveira, Marina and MARACCINI G, Orestes. Sistemas Prediais de Agua Quente. Texto Técnico- Serie TT/PCC. Departamento de Ingeniería Civil, Universidad de Sao Paulo. Ed: EPUSP, 1994. P. 60.

INCESA STANDARD. Manual de Instalación y Fontanería, San José, Costa Rica, 1983.

INDUSTRIA PAVCO S.A. Manual Técnico Tubosistemas. Colombia, 2004.

INSTITUTO COSTARRICENSE DE ACUEDUCTOS Y ALCANTARILLADOS. Proyecto de Reglamento de Prestación de Servicios y de Instalaciones Sanitarias, 1984.

INSTITUTO DE VIVIENDA Y URBANISMO. Reglamento de Construcciones. Imprenta Nacional, Costa Rica, 1987.

MÉNDEZ, G., Correspondencia DIS 1606 89 dirigida a Comisión de Redacción de Código de Instalaciones Hidráulicas y Sanitarias en Edificaciones, 1989.

MERRICK, C. Instalaciones en los edificios, Ed. Gustavo Gili S.A., 6th ed., Barcelona, 1982.

MINISTERIO DE DESARROLLO ECONÓMICO DE LA REPÚBLICA DE COLOMBIA. Reglamento Técnico del Sector de Agua Potable y Saneamiento Básico RAS-2000, Sección 2, título D. 2000.

MINISTERIO DE SALUD. Programa Nacional de Saneamiento Ambiental. Programa de Control de la Contaminación del Agua, Depto. de Saneamiento Ambiental, April, 1982.

MINISTERIO DE SANIDAD Y ASISTENCIA SOCIAL. Notas Técnicas de Normas Sanitarias para Edificaciones, Gaceta Oficial de la República de Venezuela, No. 4044 Extraordinario, 18 de setiembre de 1988.

MISTERIO DE VIVIENDA Y SERVICIOS BÁSICOS DE LA REPÚBLICA DE BOLIVIA. Reglamento Técnico de Diseño para Proyectos de Estaciones Elevatorias de Aguas Residuales. 2001.

NACOBRE S.A. Criterios de Diseño para Redes de Agua Potable Empleando Tuberías de PVC. Industrias Nacobre S.A de C.V. Manual Técnico.

NACOBRE S.A. Criterios de Diseño para Redes de Alcantarillado Empleando Tuberías de PVC. Industrias Nacobre S.A de C.V. Manual Técnico.

NIELSEN, L. S., Diseño Estándar en Plomería, Compañía Ed. Continental, 1st ed. in Spanish, México, 1965.

Pump Handbook, Klein, Schanzlin & Becker, Germany, 1968.

RODRÍGUEZ Avial, M., Instalaciones en los edificios. Fontanería y saneamiento., Ed. Dossat, Madrid., 1953.

ROJAS Castro, Víctor. Instalaciones mecánico sanitarias en edificios. UCR.

SISTEMAS HIDRONEUMÁTICOS S.A. Manual para el cálculo y selección del sistema de bombeo. Venezuela, 1998.

Specification Drainage Engineering Guide: Oil, sand and sediment interceptor. (Technical brochure). Zurn S.A.

URALITA. Catálogo Técnico de Tuberías para la Edificación. Departamento Técnico División Sistemas de Tuberías. Grupo Uralita. Madrid, 2004.

U.S. Environmental Protection Agency. Onsite Wastewater Treatment Manual System. Office of Water of the Office of Research and Development. 2002.

VAHRSON, W.G., and DERCKSEN, P. Lluvias de altas intensidades y obras de conservación de suelos en Costa Rica, América Central. Agronomía Costarricense, Vol. 14, No. 2, 1990.

WATER RECLAMATION (NETWORK) DEPARTMENT. Code of Practice on Sewerage and Sanitary Works. Public Utilities Board. Singapore, 2004. 82 p.

On the Internet Illinois Plumbing Code On Line http://www.ilga.gov/commission/jcar/admincode/077/07700890sections.html Manuales y Reglamentos del Ministerio de Vivienda y servicios Básicos de Bolivia http://www.aguabolivia.org/ Agencia de Protección Ambiental de U.S.A (USEPA) http://www.epa.gov/ Manuales técnicos de Nacobre S.A http://www.nacobre.com.mx/ Florida Building Code On line http://www2.iccsafe.org/'orida_building_code/ (Note from Sinalevi: By means of an Errata published in La Gaceta N° 198 of October 20, 2017, page N° 44, the following is established: "In Alcance N° 38 of La Gaceta Nº 37 of February 21, 2017, the 'Código de Instalaciones Hidráulicas y Sanitarias en Edificaciones, Edición 2017' was published, in which, due to a material error, the publication of article 12 regarding the entry into force of the standard was omitted, a period that was agreed upon by agreement N° 06 of session N° 02-15/16-AER of September 27, 2016, of the Asamblea de Representantes of the Colegio Federado de ingenieros y de Arquitectos de Costa Rica, it being correct to set forth, read, and understand the following:

"Article 12. Effective Date. This standard shall enter into force 6 months after its publication in the Diario Oficial La Gaceta."") 13. ANNEXES 13.1 ANNEX A. RECOMMENDATIONS FOR THE DESIGN, CONSTRUCTION, AND INSTALLATION OF GREASE INTERCEPTORS Article A-1 The provisions of this annex are a series of recommendations for the design, construction, and installation of grease interceptors for commercial kitchens.

Article A-2 All material drained from the fixtures shall enter the interceptor only through the inlet pipe.

Article A-3 Design and location.

It shall comply with the following requirements:

. Interceptors shall be constructed in accordance with the standards approved by the Ministerio de Salud and the entity administering the aqueduct.

. They shall be installed in a manner that allows easy access for cleaning, inspection, and removal of grease. They shall have an adequate number of cleanouts to allow access for cleaning the interceptor. The cleanout cover shall prevent the ingress and egress of liquids and gases, having a minimum opening of sixty centimeters (0.60 m).

. In areas where vehicular traffic may exist, the interceptor shall be designed to withstand this load.

. They may not be installed in areas of the building where food is handled.

. Interceptors shall be installed as close as possible to the fixtures they serve.

Article A-4 Construction requirements.

Grease interceptors shall comply with the following requirements:

. In the case of businesses that must submit reports on the state of their drains, a sampling box or other element shall be provided at the interceptor outlet to allow the corresponding authority to take samples of the interceptor drainage.

. The plans shall contain all dimensions, capacities, reinforcements, and, where required, the structural design calculations.

. The grease interceptor shall have two compartments. The inlet compartment shall have a capacity equal to two-thirds (2/3) of the total volume, having a liquid volume of at least one thousand two hundred (1200) liters. The outlet compartment shall have a minimum capacity of one-third (1/3) of the total volume.

. The liquid depth shall not be less than thirty-six centimeters (0.36 m) and not greater than one hundred eighty centimeters (1.80 m).

. Grease interceptors shall have at least one thousand square centimeters (0.1 m²) of surface area for every one hundred eighty-three liters (183 L) of capacity.

. Access cleanouts shall be provided for each compartment of the interceptor. For interceptors having a length greater than six meters (6 m), accesses shall be located every three meters (3 m). Access cleanouts shall have a minimum dimension of fifty centimeters (0.50 m), either in diameter or per side.

. On both the inlet and outlet pipes, a T-wye or a similar flow device shall be installed. Each T-wye shall extend at least ten centimeters (0.10 m) above the liquid level.

. The division between compartments shall be made of suitable material. The division shall extend above the liquid level by at least fifteen centimeters (0.15 m). Communication between compartments shall be achieved by means of a 90-degree elbow of the same size as the inlet T-wye.

. The liquid level shall be at a minimum distance of twenty-two centimeters (0.22 m) from the top of the interceptor. The air chamber shall have a minimum capacity of 12.5% of the liquid volume of the interceptor.

. The walls of the interceptor shall have a minimum thickness of seventy-five millimeters (0.075 m).

Article A-5 Grease interceptors shall be subjected to inspection and testing to verify their watertightness. The test consists of filling the interceptor with water up to the flow line of the outlet pipe and verifying the existence of leaks. The pipes entering and leaving the interceptor shall be tested in the same manner as the drainage pipes.

13.1.1 DIMENSIONING CRITERIA Article A-6 The parameters for dimensioning a grease interceptor are the hydraulic load and the grease storage capacity, for one or more fixtures.

Article A-7 The size of the interceptor may be calculated using either of the two methods indicated below:

Method 1. The size of the interceptor shall be estimated based on the maximum number of meals to be served per hour, using the data from table A.1.

Method 2. The size of the interceptor shall be estimated based on the drainage fixture units and the retention time.

13.2 ANNEX B. Recommendations on individual systems for the treatment and disposal of domestic or ordinary wastewater Drainage beds with infiltration trenches Article B-1 The recommended procedure for calculating the appropriate length of a drain in beds with infiltration trenches is detailed below.

A. With the obtained infiltration rate T (min/cm) of the ground, the maximum water application rate (m/s or liters/(m² day)) is deduced from current references. These rates (v) have been suggested, for the case of Costa Rica, by the Ministerio de Salud or by the AyA.

Data:

. T (infiltration rate) = time between readings / last difference in water levels in the hole; units: (min/cm).

. Vp (Infiltration rate) = 127.75⁄√T ; units: (liters/m²/day). The professional responsible for the design may use other formulations accepted by good professional practices that are adequately suited to site conditions.

. The alternative means is to obtain the data for that infiltration rate from the data indicated in table B.1:

Notes:

1. Higher result, inadequate for absorption wells 2. Higher result, inadequate for absorption systems B. At this level of the calculation process, it is necessary to know the amount of water that the dwelling or the system under analysis will be contributing, which would be the daily water volume or contribution (liters/day).

. Flow or discharge (Q) of water that the soil will receive per day. For example, one person could represent a discharge (return flow) of 162 liters/day (without the use of low-water-consumption fixtures) ==> a house with 6 people will produce (162 x 6) = 972 L/day; therefore, making the conversions, that value is: Q = 972 L/day = 0.972 m³/day = 0.00001125 m³/s = 1.125 x 10⁻⁵ m³/s C. By comparing the previous data (infiltration rate and return flow to be disposed of), the required absorption area or infiltration area (Ai) in square meters is deduced using the following equation:

D. Additionally, in this calculation process to define the required infiltration field, other factors are applied. These are coefficients that take into consideration the effect of rain and the cleanliness or type of covering (grass only, pavers, concrete tire strips, among others) that the surface where the infiltration area will be placed will have. Based on the prevailing conditions and the application of these coefficients, the value previously calculated as the absorption area is increased, to consequently obtain, as a new datum, the value of the land surface required for the sought infiltration field.

. Precipitation (Fp) (factor greater than or equal to 2.5). That value of 2.5 is assumed for San José according to its average annual precipitation and is adjusted upwards, according to the proportion that the average annual precipitation of the place under study has.

. Top covering (rc). It is considered zero (0) if nothing is covering the ground surface and nearly one (1) if it is covered.

Then, E. The geometry of that calculated infiltration field is obtained by fixing characteristics such as the trench width and the depth of graded filter material under the drainage pipes. According to that width and that depth of material under the drains, also from hydraulic assessments, a correction factor is obtained with which a new parameter is fixed, known as the effective perimeter (Pe = corrected wetted perimeter).

. A value for the trench width (W) is fixed. A distance (D) of gravel under the pipe is fixed.

. With W and D in centimeters, in that equation (this Pe value can also be taken from existing tables).

F. The length of the trenches to be used will be obtained from the relationship that can be made between the calculated absorption area (Ai) and that effective perimeter datum. It remains then to establish another relationship between the value of the surface to be occupied by the entire infiltration field and the calculated length of the trenches. In this way, the separation between trenches or the required width of the total surface of the intended infiltration field will be established.

G. Water table. It is necessary not to forget the importance of determining and verifying the depth at which groundwater is found.

13.3 ANNEX C. RECOMMENDATIONS ON INDIVIDUAL SYSTEMS FOR THE TREATMENT AND DISPOSAL OF DOMESTIC OR ORDINARY WASTEWATER DIMENSIONS OF A SEDIMENTATION/BIODIGESTER TANK (SEPTIC TANK)

The recommended procedure for defining the dimensions of a sedimentation/biodigester tank, using the rational method, is detailed below.

The procedure is based on the formulas proposed by the research of Drs. D.D. Mara and G.S. Sinnatamby, whose rational method is for calculating the appropriate functioning of a septic tank in tropical climate locations. In this way, the appropriate analytical means are established to achieve the magnitude of each of the volumes that are definable in the treatment process carried out inside a septic tank.

Thus, the following is presented:

14. FIGURES A large part of the figures below are adapted from the Proyecto de Reglamento de Prestación de Servicios y de Instalaciones Sanitarias, by the AyA. Figure 5.1 is adapted from the Manual de Instalación y Fontanería, by Incesa Standard, provided by Arch. Mario Peraza. To all of them, we are grateful for allowing their reproduction.

San José, February 7, 2017.

El presente Código tiene como objetivo establecer los requisitos mínimos para proteger la salud pública, la seguridad, el bienestar general en las edificaciones destinadas para uso, ocupación o habitación humana y que se construyan en el territorio de la República de Costa Rica.

El presente Código deberá cumplirse durante las etapas de diseño, construcción, instalación, reparación, readecuación, reemplazo, relocalización, adición o remodelación de las edificaciones.

Este Código comprende las instalaciones sanitarias e hidráulicas de agua potable (fría y caliente), desagüe de aguas residuales, ventilación de las instalaciones sanitarias, drenaje de aguas pluviales y distribución de gas LP, todas ellas relacionadas con las edificaciones.

Por su naturaleza, las instalaciones sanitarias e hidráulicas y de gas LP deben ser diseñadas, construidas, instaladas, reparadas, reemplazadas o remodeladas mediante metodologías y técnicas probadas, así como con materiales de probada capacidad. Sin embargo, no se limita el uso de materiales y métodos de diseño alternos que no estén específicamente señalados por este Código, siempre y cuando el profesional responsable del diseño demuestre que el uso de la alternativa permite el cumplimiento de los objetivos descritos en el presente Código.

Independientemente del grado de refinamiento en el análisis y diseño, o de la calidad de los materiales, o de la construcción, es necesario que todas las instalaciones para las que este Código establece normas estén bien concebidas y proyectadas, con el fin de alcanzar los objetivos establecidos.

Las disposiciones contenidas en este Código representan requisitos mínimos en procura de un adecuado desempeño de las instalaciones. No obstante, la labor del profesional responsable del diseño no se debe limitar al cumplimiento irreflexivo de estas disposiciones, sino que debe procurar la satisfacción de los objetivos establecidos en el Código y adoptar, de ser preciso, criterios alternativos más rigurosos que los establecidos por este Código.

Este Código hace referencia a disposiciones de otros códigos y normas nacionales y extranjeras. Se entiende que el Código se refiere específicamente a las versiones vigentes al momento de la revisión final del presente documento, en el mes de enero de 2017.

No obstante, el profesional responsable del diseño debe tener presentes las reformas y cambios a dichos documentos posteriores a esta fecha, en estricto apego a su mejor criterio profesional y a las reglas de ética establecidas por el Colegio Federado de Ingenieros y de Arquitectos de Costa Rica.

2. DEFINICIONES

Para los propósitos de este Código, los siguientes términos tienen el significado indicado en este capítulo:

- A - Abasto (tubo de): tubo, generalmente flexible, que sirve para conectar un inodoro, lavatorio, fregadero u otro accesorio sanitario a la alimentación principal de agua potable.

Acometida: conexión de una edificación determinada a un sistema o servicio establecido.

Agua para uso industrial: agua no necesariamente potable, ya sea por sus características físicas, químicas o biológicas; su calidad esperada dependerá de las necesidades que se deseen cubrir en cada caso.

Agua para reutilización: agua aprovechable en cualquier sistema de distribución, con excepción del sistema de distribución de agua potable.

Agua de recirculación: agua con calidad igual o superior a la del sistema donde se suministra.

Agua potable: aquella que reúne las características físicas, químicas y biológicas que la hacen adecuada para el consumo humano, de acuerdo con las disposiciones de la Organización Mundial de la Salud sobre la calidad del agua potable.

Aguas residuales: aquellas que contienen desperdicios, materiales en suspensión o solución de origen humano, animal, vegetal o químico, provenientes de las descargas de residencias, edificios comerciales o instalaciones industriales de cualquier índole; se clasifica en dos tipos: ordinaria y especial.

Agua residual especial: aquella de tipo diferente a la ordinaria; por ejemplo, aguas de procesos industriales u hospitalarios.

Agua residual ordinaria: agua residual generada por las actividades domésticas del ser humano (uso de inodoros, duchas, lavatorios, fregaderos); a menos de que se indique lo contrario, cuando en el presente Código se hable de aguas residuales, se trata de este tipo.

Alcantarillado pluvial: red pública o privada de tuberías que se utilizan para recolectar y transportar las aguas de lluvia hasta su punto de descarga a un medio receptor.

Alcantarillado sanitario: red pública o privada de tuberías que se utilizan para recolectar y transportar las aguas residuales hasta su punto de descarga a un medio receptor.

Aparato sanitario: artefacto generalmente conectado a un sistema de suministro de agua (potable o no), que la recibe sin peligro de contaminación y que la descarga a un conducto de desagüe de aguas residuales, después de ser utilizada.

Aparatos de uso privado: aquellos destinados a ser utilizados por un número restringido de personas, por ejemplo en residencias familiares, edificaciones comerciales, edificaciones hospitalarias o industriales.

Aparatos de uso público: los que están ubicados de modo que puedan ser utilizados sin restricciones por cualquier persona; estos se pueden encontrar en edificios de instituciones públicas, edificaciones comerciales, templos, estadios, centros recreativos, entre otros.

Autoridad administrativa: ente encargado de administrar y operar los sistemas públicos de acueductos y alcantarillados (AyA, municipalidades u otros).

Autoridad sanitaria: ente público encargado de fijar las normas y leyes sanitarias en cuanto a calidad del agua, así como las características y requerimientos de los efluentes (Ministerio de Salud).

AyA: Instituto Costarricense de Acueductos y Alcantarillados.

- B - Bajante: tubería en un sistema de desagües de aguas residuales o pluviales.

Batería de piezas sanitarias: cualquier grupo de piezas sanitarias similares y adyacentes, que tienen una misma tubería de abastecimiento de agua y descargan en el mismo ramal de desagüe.

Boca de limpieza: pieza o accesorio que forma parte de las tuberías de desagüe, destinada a permitir la inspección y limpieza de dichas tuberías.

Bidé: pieza sanitaria destinada al aseo de las partes íntimas del cuerpo.

- C - Caja de registro: estructura plástica, metálica o de concreto destinada a permitir la inspección, limpieza de las tuberías de desagüe, capturar lodos y objetos sólidos; también permite efectuar cambios de dirección, pendiente, diámetro y material de tubería.

Caudal: volumen de líquido o fluido que pasa por una sección de tubería o canal por unidad de tiempo; en este Código se expresa usualmente en litros por segundo.

Caudalímetro: ver hidrómetro.

CFIA: Colegio Federado de Ingenieros y de Arquitectos de Costa Rica.

Cisterna: ver tanque de captación.

Cloaca: ver colector de aguas residuales o pluviales.

Colector de aguas pluviales: tubería principal destinada a recolectar y conducir las aguas de lluvia de una edificación hasta la conexión con el alcantarillado pluvial.

Colector de aguas residuales: tubería principal, destinada a recolectar y conducir las aguas residuales de una edificación hasta la conexión con el alcantarillado sanitario.

Condominio: inmueble construido en forma horizontal, vertical o mixta, susceptible de aprovechamiento independiente por parte de distintos propietarios, con elementos comunes de carácter indivisible; estos últimos, denominados "bienes comunes", son aquellos elementos, pertenencias o servicios de dominio inalienable e indivisible de todos los propietarios, necesarios para el uso, seguridad, salubridad, conservación, acceso, recreo u ornato del inmueble.

Conexión cruzada: conexión física entre dos sistemas de tuberías, donde el agua puede fluir de un sistema a otro, dependiendo de la dirección del flujo y de la presión diferencial entre los dos sistemas.

Conexión domiciliaria de agua: tramo de tubería comprendida entre la tubería pública de agua potable y el medidor ubicado en el exterior de una edificación.

Conexión domiciliaria de desagüe pluvial: tramo de tubería comprendido entre la última caja de registro y el alcantarillado pluvial.

Conexión domiciliaria de desagüe sanitario: tramo de tubería comprendido entre la última caja de registro y el alcantarillado sanitario.

Consumo: caudal medido en la conexión domiciliaria de agua potable.

Contenedor tipo ASME: contenedor construido de acuerdo con el código y especificaciones de la Sociedad Americana de Ingenieros Mecánicos (ASME, por sus siglas en inglés).

Contenedor tipo cilindro: contenedor diseñado, construido, probado y rotulado de acuerdo con las especificaciones del Departamento de Transporte de Estados Unidos de América.

Columna de ventilación: tubería destinada a la entrada o salida de aire del sistema de desagüe de una edificación de uno o varios pisos.

Cuarto de baño: aposento en el que se ubican las piezas sanitarias destinadas a la higiene personal.

- D - Demanda: consumo de agua potable para un intervalo de tiempo dado, para un fin dado, en una edificación.

Diámetro efectivo: diámetro interior de una tubería.

Diámetro nominal: dimensión comercial o normalizada de las tuberías, que no necesariamente corresponde al diámetro efectivo.

Dispositivo conector de gas: conjunto formado por una tubería flexible o semirrígida y accesorios, que se encarga de conducir el gas combustible.

Dispositivo de desconexión rápida (GLP): dispositivo de operación manual que provee, para un equipo o una conexión de salida, un medio de conexión y desconexión de la alimentación de gas, que está equipada con un medio automático de desconexión, para cerrar el suministro de gas cuando el dispositivo está desconectado.

Dotación: medida del consumo o de la demanda expresada usualmente en litros por persona por día o su equivalente de una edificación, de acuerdo con el uso y la ocupación a que está destinada.

Desagüe indirecto: descarga de una pieza sanitaria o de cualquier otro artefacto que se realiza a través de un espacio de aire al sistema de desagüe de una edificación, mediante la utilización de un desagüe de piso u otro dispositivo adecuado.

Ducto mecánico: espacio hueco dejado en las edificaciones, de sección regular (p. e. rectangular o circular) y generalmente limitado por paredes; es utilizado para alojar tuberías de los sistemas electromecánicos o ductos de los sistemas de ventilación y aire acondicionado, con el fin de permitir su inspección, reparación o mantenimiento.

- E - Edificación: cualquier construcción o edificio destinado a uso, ocupación o habitación por personas.

Escorrentía: agua de lluvia que discurre por la superficie de un terreno.

- F - Filtración: separación física de las sustancias sólidas en suspensión en un líquido mediante el uso de medios porosos.

Filtro: dispositivo o aparato con el que se efectúa el proceso de filtración.

Flotador, válvula de: dispositivo que se mantiene en la superficie del agua de un tanque de captación y que se utiliza generalmente para registrar las variaciones de nivel o para gobernar un interruptor o una válvula.

Fluxómetro: válvula semiautomática que descarga un volumen de agua determinado para evacuar una cantidad de líquido de un accesorios sanitario (inodoro o mingitorio); usualmente se activa mediante una palanca, botón o sensor electrónico.

Fuga: pérdida de líquido a causa de la falta de estanqueidad en tanques, accesorios de la tubería, artefactos sanitarios u otro.

- G - Gasto: ver caudal.

Gas combustible: término referente para el gas licuado de petróleo (GLP, Gas LP, Propano, Butano, entre otros).

Golpe de ariete: variación de la presión que sufre una tubería y sus accesorios por efecto de cambios repentinos de la velocidad del agua.

Gradiente de energía: razón de cambio de la línea de energía, la cual describe la suma de la carga de elevación, la carga de presión y la carga de velocidad.

Gradiente hidráulico: es la razón de cambio en la línea de gradiente hidráulico, la cual representa la suma de la carga de presión y la carga de elevación; usualmente se expresa en unidades de longitud sobre un nivel de referencia.

- H - Hidrómetro: dispositivo o instrumento que sirve para medir el caudal.

Hidroneumático: ver tanque hidroneumático.

- I - Instalación sanitaria: conjunto de tuberías, equipos o dispositivos destinados al abastecimiento y distribución del agua, y a la evacuación de desagües y su ventilación dentro de la edificación.

Instalaciones de gas: término que hace referencia a cualquier tanque, recipiente, equipo regulador, medidores y accesorios necesarios para el almacenamiento y la distribución del gas combustible para cualquier edificio o local.

Interruptor de flotador: flotador equipado para el mando de una bomba u otros equipos, cuyo funcionamiento está ligado a las variaciones de nivel de un líquido en un depósito.

Interruptor de vacío: dispositivo de acción mecánica destinado a evitar el reflujo de agua.

Interceptor: dispositivo diseñado e instalado para separar y retener materiales indeseables o peligrosos que puedan contener las aguas residuales de una edificación, permitiendo, a su vez, el desagüe por gravedad de dichas aguas a los conductos de desagüe.

Interceptor de grasa: dispositivo utilizado para efectuar la separación de la grasa y de los aceites en los vertidos de los establecimientos donde se preparan alimentos; tales dispositivos podrán ser del tipo para ubicar en exteriores, o estar ubicados cerca del accesorio sanitario; son conocidos también como trampa de grasa.

- J - Junta de dilatación: dispositivo destinado a absorber las variaciones de longitud de las tuberías, producidas por cambios de temperatura.

Juntas abiertas: son las juntas que no son herméticas y que permiten una separación entre las tuberías que las forman.

Junta flexible: permite ligeros desplazamientos o rotaciones de una tubería para absorber vibraciones o solicitaciones de cargas exteriores, lo mismo que los efectos de situaciones de régimen transitorio en el sistema.

Junta de dilatación sísmica: accesorio utilizado en los sistemas de tuberías para atravesar juntas sísmicas entre estructuras o ingresar de la parte exterior hacia lo interno del edificio; es una junta extremadamente flexible, con movimiento en todas las direcciones para evitar la rotura en caso de sismo.

- L - Llave de purga: válvula que permite descargar agua o sedimentos de una tubería o recipiente.

- M - Medidor de agua: ver hidrómetro.

Memoria de cálculo: relato escrito complementario de los planos del proyecto y explicativo de los determinantes de su funcionamiento.

mca: sigla de la unidad de presión metro de columna de agua o cabeza de agua; un (1) mca equivale a 9806,65 MPa a 4 °C.

- N - Nivel de rebalse: es el correspondiente al nivel de descarga del exceso de agua que ingresa a un tanque de captación o pieza sanitaria.

- P - PE: sigla común para el polietileno, tanto en inglés como español.

PEAD: sigla común para el polietileno de alta densidad (siglas en inglés HDPE).

Pérdida de carga: es la variación en altura de la línea de gradiente hidráulico, es decir, es igual al cambio en la suma de las cargas de presión y elevación; se origina en la disipación de energía ocasionada por la fricción del fluido al escurrir a través de una tubería, y equivale a los términos "pérdida de cabeza" o "pérdida de presión".

Presión de servicio: es la presión estática a la entrada de un sistema de tuberías en su régimen de operación normal.

Presión dinámica: corresponde al término de energía cinética por unidad de volumen.

Presión estática: es el valor de la presión en un sistema de tuberías en condiciones de flujo nulo; se puede considerar como invariante en el tiempo.

Prevista: tuberías y accesorios que normalmente se colocan sobre las tuberías principales de las redes de abastecimiento de agua o alcantarillado, con el propósito de ser utilizadas para las instalaciones sanitarias de los futuros usuarios.

Probabilidad de uso simultáneo: probabilidad de que un cierto número de piezas sanitarias sean utilizadas al mismo tiempo, en un momento dado.

PVC: sigla para el cloruro de polivinilo.

- R - Ramal de alimentación: tubería que abastece de agua a una pieza sanitaria o a un grupo de ellas.

Ramales de descarga: tuberías que reciben directamente los efluentes de las piezas sanitarias.

Ramales de desagüe: tuberías que reciben los efluentes de los ramales de descarga.

Rebalse: tubería o dispositivo destinado a evacuar eventuales excesos de agua en los tanques de almacenamiento, piezas sanitarias u otros accesorios sanitarios.

Red pública: tubería del sistema de distribución del acueducto público o del sistema de recolección de aguas residuales o pluviales de los entes públicos.

Reflujo: flujo en sentido inverso al previsto para un conducto o pieza sanitaria.

Registro: abertura para inspección o limpieza de tanques o trazados de tuberías.

- S - Sello de agua (sello hidráulico): volumen de agua existente en el sifón de una pieza sanitaria y que impide el reflujo de gases, olores y la entrada de animales desde la tubería de descarga hacia la pieza.

Separador: ver interceptor.

Sifón: accesorio cuya función es mantener el sello de agua en la descarga de las piezas sanitarias.

Sifonaje: rotura o pérdida del sello de agua del sifón de una pieza sanitaria, como resultado de la pérdida del agua contenida en él por el efecto de presiones positivas o negativas en el sistema de desagüe.

Sistema de alimentación directa: suministro de agua a los puntos de consumo de una edificación directamente por la presión de servicio de la red pública, cuando los valores mínimos de esta son adecuados para satisfacer continuamente los requerimientos hidráulicos de las instalaciones del abonado.

Sistema de alimentación indirecta: suministro de agua a los puntos de consumo que no utiliza directamente la presión de servicio de la red pública.

Sistema de bajante único de desagüe: sistema de desagüe de un solo conducto en el que se omiten todos o casi todos los conductos de ventilación.

Sistema hidroneumático: sistema que suple agua bajo ciertas condiciones de presión a las tuberías de distribución, por medio de un acumulador de energía por compresión de aire; generalmente, se compone de una bomba y un tanque hidroneumático.

Sistema de presión constante: sistema que suple agua bajo ciertas condiciones de presión a las tuberías de distribución por medio de un sistema de bombeo; generalmente, se compone de un arreglo de bombas con variador de frecuencia y un sistema de censado de presión.

Sistema de reutilización: sistema que conduce las aguas a reutilizar dentro de una edificación.

Sumidero: accesorio sanitario, con o sin sello hidráulico, destinado a recibir aguas residuales o pluviales del piso de un baño, patio o techo.

- T - Tanque de captación: depósito de agua potable del cual se abastecen los artefactos sanitarios de las edificaciones; puede ser elevado o enterrado, según el espacio disponible para la edificación.

Tanque elevado: tanque de captación para el almacenamiento de agua ubicado en los pisos superiores de una edificación o sobre una estructura concebida para ese fin.

Tanque hidroneumático: reservorio en el que se almacenan agua y aire a presión.

Trampa: ver interceptor.

Tubería: conducto de sección geométrica regular (generalmente circular) destinado al flujo de un fluido.

Tubería de impulsión: la comprendida entre la descarga de un equipo de bombeo y la entrada a un tanque elevado o punto de consumo.

Tubería de distribución: tubería destinada a llevar agua a todas las piezas sanitarias de una edificación.

Tubería de retorno: tubería que conduce agua de regreso al sistema de producción, en un circuito con recirculación.

Tubería de succión: la comprendida entre un tanque de captación y la entrada a un equipo de bombeo.

Tubería de ventilación: tubería con salida a la atmósfera destinada a permitir la entrada de aire a los sistemas de desagüe y la salida de gases de esos sistemas, con el objetivo de impedir la ruptura del sello de agua de los sifones sanitarios y mantener el flujo a lámina libre en los desagües.

Tubo de ventilación auxiliar: tubería vertical que une un ramal de desagüe al tubo ventilador del circuito correspondiente, o tubo que une el de ventilación principal con el bajante.

Tubo de ventilación en circuito: tubo de ventilación secundario ligado a un ramal de desagüe y que sirve a un grupo de piezas sin ventilación individual.

Tubo de ventilación individual: tubo de ventilación secundario ligado al sifón del tubo de descarga de una pieza sanitaria.

Tubo de ventilación principal: tubo de ventilación vertical en el que se conectan las ventilaciones individuales y que termina en una extensión de ventilación sobre el techo del edificio.

Tubo de ventilación secundario: tubo de ventilación que tiene el extremo superior ligado a una tubería ascendente u otro tubo de ventilación, sea principal o secundario.

Tubería horizontal: para los efectos de estas normas, es cualquier tubería o pieza de conexión instalada en posición tal que forme un ángulo menor de 45° con la horizontal.

Tubería vertical: para los efectos de estas normas, es cualquier tubería o pieza de conexión instalada en posición tal que forme un ángulo de 45° o menos con la vertical.

- U - Unidades de accesorios: unidad empírica de caudal escogida de tal manera que la demanda de agua de las piezas sanitarias pueda ser expresada como múltiplo de esta unidad que se toma como base; la unidad de accesorio de una pieza depende del tipo de pieza, de la duración del gasto, del intervalo entre los usos y de la probabilidad del uso simultáneo; su definición varía según los distintos métodos empleados en el cálculo de los caudales de alimentación de agua potable.

Unidades de descarga: unidad empírica de caudal similar a la anterior, donde las descargas de las piezas sanitarias pueden ser expresadas como múltiplos de esta unidad que se toma como base.

Unión flexible: ver junta flexible.

Urinario: lugar destinado para orinar y, en especial, el dispuesto para el público.

- V - Vacío: cualquier presión menor a la presión atmosférica local.

Válvula de retención: válvula que evita la circulación del flujo en una dirección contraria a la establecida, generalmente conocida como válvula antirretorno, válvula de contraflujo o válvula "check".

Válvula de seguridad: dispositivo destinado a evitar la elevación de la presión por encima de un límite determinado, acorde con la presión normal de funcionamiento; usualmente se encuentran en sistemas de agua caliente, de vapor y de gas LP.

Válvula interruptora de vacío: interruptor de vacío.

Válvula reductora de presión: válvula de control de operación hidráulica que reduce la presión alta, aguas arriba, a una presión menor y constante aguas abajo, sin que le afecten las fluctuaciones en la demanda o en la presión de aguas arriba.

Ventilación artificial o mecánica: es la introducción de aire fresco y no contaminado en un ambiente dado de una edificación, o la remoción del aire vaciado del mismo, permitiendo la entrada de aire fresco y no contaminado; para ello utiliza medios mecánicos, tales como ventiladores de impulsión o de extracción o ductos de ventilación.

Ventilación húmeda: es el método de ventilar sifones de piezas sanitarias utilizando un conducto de desagüe de una pieza sanitaria cuyo sifón esté individualmente ventilado y se instale a no menos de 40 cm sobre el nivel de piso.

3. NORMAS GENERALES

Toda edificación destinada a uso u ocupación humana debe estar provista de un sistema de abastecimiento de agua potable. Este sistema no debe afectar en ningún momento el grado de pureza del agua destinada al consumo humano y debe garantizar su suministro (caudal y presión suficiente en todos los puntos de consumo para su adecuado funcionamiento, según lo establecido en este Código.

Toda edificación destinada a ocupación o habitación humana, ubicada dentro de un área servida por un abastecimiento público de agua en condiciones de prestar servicio, deberá aprovechar dicho suministro.

Cuando el abastecimiento público no se encuentre en condiciones de prestar servicio adecuado, ya sea por calidad, cantidad o continuidad, se permitirán sistemas de suministro alterno, siempre que la fuente de agua y su potabilización cumplan con los requisitos establecidos en este Código, así como los requerimientos establecidos por las autoridades sanitarias y administrativas correspondientes. Se debe prestar atención a la cantidad de minerales presentes en el agua que suministra el sistema alterno, ya que el agua desmineralizada o con contenido bajo de minerales es corrosiva, así como perjudicial para la salud humana y de los animales.

Las edificaciones podrán disponer de un abastecimiento de agua no potable o de un sistema de reutilización de agua para fines diferentes al consumo humano, de manera que se contribuya con la disminución del consumo de agua potable y a la gestión adecuada de este recurso natural. Entre las consideraciones para este tipo de sistema se encuentran: a) dicho abastecimiento deberá contar con redes separadas, sin conexión alguna con el sistema de agua potable, b) que se advierta a todos los usuarios de la edificación, por medio de avisos claramente marcados y profusamente distribuidos, acerca de la falta de potabilidad de dicho sistema, y c) que se distingan las tuberías utilizando los colores respectivos de acuerdo con el artículo 3-9.

Todo sistema de alimentación y distribución de agua potable se protegerá contra conexiones cruzadas.

Toda edificación destinada a ocupación humana deberá poseer un sistema independiente para la evacuación de las aguas residuales y un sistema independiente para la adecuada conducción y evacuación de aguas pluviales, conforme con lo establecido en este Código, sean estos sistemas individuales (recolección y tratamiento) o sistemas administrados por entes públicos, según corresponda. No existirán conexiones cruzadas entre los sistemas de evacuación de aguas residuales y de aguas pluviales.

Las instalaciones sanitarias para desagüe de aguas residuales deberán diseñarse y construirse en forma tal que permitan un rápido escurrimiento de los desechos, se eviten obstrucciones, impidan el paso de gases, olores y animales de la red pública al interior de las edificaciones, que no permitan el escape de líquidos ni la formación de depósitos en el interior de las tuberías e impidan la contaminación del agua de consumo. Ningún desagüe tendrá conexión alguna con el sistema de agua potable por ningún motivo, así como tampoco con el sistema de desagüe pluvial.

Las tuberías de ventilación sanitaria deberán permitir una evacuación adecuada de los gases que se produzcan o ingresen al sistema y garantizar condiciones de flujo a presión atmosférica, para evitar la pérdida de los sellos hidráulicos e impedir la formación de bolsas de gases dentro de las tuberías de desagüe.

Los diversos sistemas de tuberías de las edificaciones se deberán identificar de acuerdo con la norma oficial para la utilización de colores en seguridad y su simbología establecida.

Para los casos no contemplados en esta norma, se podrá utilizar como referencia la norma Inteco 31-07-03: Código de colores para la identificación de fluidos conducidos en tuberías.

Las aguas residuales industriales, condesados calientes, las sustancias corrosivas y materias que puedan causar daños o interferir con los procesos de tratamiento existentes o previstos, no podrán ser descargadas directa ni indirectamente al alcantarillado sanitario, salvo que sean sometidas previamente a tratamiento satisfactorio de acuerdo con las directrices y normas de la autoridad sanitaria y administrativa correspondiente, que son:

. Reglamento de vertido y reuso de aguas residuales.

No se permitirá verter o descargar aguas pluviales, superficiales, freáticas o de drenajes al alcantarillado de aguas residuales. Los sistemas de aguas residuales y de aguas pluviales de las edificaciones serán total y completamente independientes.

Toda edificación ubicada dentro de un área servida por un alcantarillado sanitario en condiciones de prestar servicio deberá descargar sus aguas residuales en dicho alcantarillado, excepto en los casos cubiertos por los artículos 3-14 y 3-15. La interconexión de la conexión domiciliaria con el alcantarillado sanitario será realizada bajo la autorización y supervisión de la autoridad administrativa del servicio de alcantarillado.

Cuando no exista un alcantarillado sanitario con capacidad de prestar servicio a la edificación, se permitirá el tratamiento y desecho de las aguas residuales por medio de sistemas individuales, siempre que cumplan con las normas establecidas por las autoridades sanitarias correspondientes (Ministerio de Salud y AyA).

Cuando la conducción o descarga de las aguas residuales o de lluvia no pueda hacerse por gravedad, deberá efectuarse el bombeo de las mismas de acuerdo con lo establecido en este Código. En caso de instalaciones domésticas unifamiliares, se permitirá el desecho de las aguas residuales mediante sistemas domésticos de tratamiento.

En las poblaciones, áreas suburbanas y rurales, así como lugares de trabajo donde no exista red de alcantarillado sanitario ni posibilidad de desecho de las excretas por arrastre de agua, estas deberán depositarse en unidades para el tratamiento seco, húmedo, por compostaje u otra forma satisfactoria, siempre que se cumplan los requisitos mínimos establecidos en este Código y por la autoridad sanitaria.

Las instalaciones hidráulicas, sanitarias y de gas LP deberán diseñarse y ejecutarse teniendo en cuenta el aspecto estructural de la edificación, evitando cualquier daño o disminución de la resistencia de las paredes, columnas, vigas, cimentaciones y cualquier otro elemento estructural, tal como lo indica el Código Sísmico de Costa Rica.

Los materiales empleados en las instalaciones de los sistemas de desagüe de los edificios deberán cumplir con los requisitos y especificaciones incluidos en este Código.

Las instalaciones sanitarias, hidráulicas y de gas LP cubiertas por este Código deberán ser proyectadas y diseñadas por profesionales registrados en el Colegio Federado de Ingenieros y de Arquitectos de Costa Rica, quienes deberán seguir las disposiciones del presente Código.

Los profesionales responsables de las instalaciones sanitarias, hidráulicas y de gas LP de las edificaciones están obligados a cumplir con las disposiciones del presente Código y serán responsables de las consecuencias de la mala ejecución de las instalaciones, empleo de materiales inapropiados y por cualquier alteración que sufran los planos de las obras.

En el caso de edificios para condominios, se deben respetar las disposiciones de la ley n.º 7933, Ley Reguladora de la Propiedad en Condominios, y su reglamento.

En el caso de construcciones donde sea notificado por la autoridad correspondiente que es necesario mantener un nivel de escorrentía del terreno, se deberá gestionar la escorrentía mediante la instalación de un sistema de retención o de detención, el cual deberá cumplir con los requisitos de este Código y los criterios dictados por la institución responsable del acueducto.

Las instalaciones hidráulicas, sanitarias y de gas LP deberán diseñarse y ejecutarse teniendo en cuenta la seguridad humana y la protección contra incendios, evitando cualquier afectación o disminución de la protección de las barreras cortafuego y humo en las paredes, columnas, vigas, cielos, entrepisos, y cualquier otro elemento de protección pasiva, tal como lo indica el Reglamento sobre seguridad humana y protección contra incendios.

4. DOTACIONES DE AGUA POTABLE

Las dotaciones mínimas de agua para uso doméstico, comercial, industrial, riego de jardín y otros fines se calcularán de acuerdo con lo establecido en la tabla 4.1.

Notas:

(1) No incluye dotación por cocina, lavandería o restaurante.

(2) La dotación hace referencia a litros/día por cama, según mediciones realizadas en dos hospitales nacionales (Hospital México y Nacional de Niños). Se deberá incrementar la dotación en caso de que el hospital cuente con lavandería.

(3) En ningún caso, la dotación será menor de 2000 litros por día (2000 l/día).

(4) Dotación en litros por metro cuadrado de área útil.

(5) Dotación en litros por metro cuadrado.

(6) Dotación en litros por kilogramo de ropa por lavar.

(7) Dotación en litros por día por equipo de lavado.

(8) Dotación en litros por día por cada 100 aves.

5. PIEZAS SANITARIAS 5.1 NÚMERO REQUERIDO DE PIEZAS SANITARIAS

El número y tipo de piezas sanitarias que deberán ser instaladas en los baños, cuartos de aseo, salas de lactancia, cocinas y otras dependencias de un edificio o local serán proporcionales al número de personas servidas y según el uso a que se les destine, de acuerdo con lo requerido en el presente Código. También se podrán utilizar las indicaciones que realiza el Reglamento de Construcciones al respecto, procurando siempre utilizar la mayor cantidad de accesorios.

Cuando en un local se realice un cambio en el uso al cual se destina, deberán realizarse las modificaciones necesarias para cumplir con los requerimientos de este Código.

En todo tipo de edificaciones, sean públicas o privadas, donde exista concurrencia o atención al público, se deberá disponer de servicios sanitarios con facilidades de acceso para el uso de las personas adultas mayores o para personas con discapacidad. Estos baños especiales deberán cumplir con los requerimientos dados por el Reglamento de la Ley n.º 7600, Sobre la Igualdad de Oportunidades para Personas con Discapacidad y con el Reglamento de Construcciones.

En todo tipo de edificaciones, sean públicas o privadas, donde laboren treinta (30) o más mujeres se deberá contar con al menos una sala de lactancia materna para que las madres, de manera discrecional, puedan dar de mamar, extraer su leche y dejarla almacenada. Esta sala será un espacio exclusivo para dicho propósito y deberá contar con un área mínima de 3m×3m, con ventilación e iluminación adecuada, preferiblemente natural, así como condiciones higiénicas, de seguridad y privacidad apropiadas. Como mínimo, la sala deberá contar con un lavatorio para el lavado de manos. El número de total de salas por edificación y sus dimensiones deberá estar en proporción razonada con el número total de mujeres en lactancia que se espera laboren en la edificación, partiendo de la

En todo tipo de edificaciones, sean públicas o privadas, donde exista concurrencia o atención de público y con asistencia infantil o familiar se deberá de disponer de mesas para cambio de pañales en los cuartos de baño de hombres y de mujeres, o adecuar baños destinados únicamente para su uso y atención. Si la edificación dispone de un solo cuarto de baño unisex, este deberá disponer de una mesa para cambio de pañales.

Alternativamente, y salvaguardando la privacidad y seguridad de los menores, se podrá disponer de mesas para cambio de pañales fuera de los cuartos de baño, en cuyo caso deberán de proveerse con un lavatorio, como mínimo, para el lavado de manos, así como también con un área adecuada para la disposición de los residuos sólidos. Las mesas para cambio de pañales deberán tener un espacio libre mínimo debajo del equipo de 760×1220 mm (30×48 pulgadas) y estar instalados a una altura máxima de 865 mm (34 pulgadas), cuando la mesa se encuentre abierta. Se recomienda su instalación cerca de un lavamanos y de un contenedor de residuos sólidos así como estar ubicadas en las zonas comunes del baño, fuera de las rutas de movimiento. Se debe evitar la colocación de las mesas para cambio de pañales dentro de cualquier compartimiento de inodoro, a fin de no atar innecesariamente el equipo al compartimiento. Colocarlas en un baño familiar es también una buena opción.

En todo tipo de edificaciones, sean públicas o privadas, donde exista concurrencia o atención de público y con asistencia infantil o familiar, se deberá de disponer de asientos de protección para niños en los compartimientos de los inodoros; estos asientos facilitan un lugar seguro y cómodo para los infantes, por lo general con un máximo de peso de hasta 22,5 kg (50 lb). Estos asientos serán instalados dentro del compartimiento de los inodoros, para proporcionar acceso visual y físico. Se instalarán a una altura desde el piso hacia la parte inferior del asiento en modo operativo no menor de 380 mm (15 pulgadas).

En su instalación se deber evaluar la operatividad y alcance del equipo, tanto en modo activo como inactivo, y cuando el equipo esté en uso, se deberá garantizar que exista espacio suficiente para maniobrar alrededor del infante sentado.

5.1.1 EDIFICACIONES UNIFAMILIARES Y MULTIFAMILIARES

Toda residencia unifamiliar estará dotada de al menos un cuarto de baño con inodoro, lavatorio y ducha. La cocina dispondrá de un fregadero y, en sitio aparte, se proveerá una batea o pila para lavar ropa.

Excepción: se podrá omitir la pila de lavar en edificaciones unifamiliares múltiples de un solo dormitorio o de un solo ambiente o de tipo estudio, siempre que se instalen estas piezas en sitio techado de la edificación, en proporción no menor de una batea por cada tres edificaciones unifamiliares.

5.1.2 EDIFICACIONES PARA COMERCIO U OFICINAS

Los edificios destinados a locales comerciales u oficinas deberán dotarse, como mínimo, de servicios sanitarios en la forma, tipo y número siguientes:

a. En locales con un área hasta de ciento cincuenta metros cuadrados (150 m2), o donde el número de empleados y clientes se estime que sea menor a quince (15), se dispondrá de por lo menos un cuarto de baño unisex dotado de inodoro y lavatorio, para los requerimientos de los empleados y consumidores, sean estos hombres o mujeres.

b. En locales con un área mayor a ciento cincuenta metros cuadrados (150 m2) se dispondrá de servicios sanitarios separados para hombres y mujeres, dotados, cada uno, de las piezas sanitarias que indica la tabla 5.1. Al utilizar esta tabla, se deberá usar la situación más crítica, ya sea la que establezca el número de personas o bien la que imponga el área del local.

c. Cuando se proyecte usar servicios sanitarios comunes a varios locales, se requerirá cumplir con lo especificado en el punto b de este artículo. Además, en edificio de varios pisos se proveerá por lo menos de un cuarto de baño para hombres y otro para mujeres en cada piso.

Nota: el área del local se estima a partir del número de personas, considerando una persona cada 10 m2 y que la población está igualmente dividida entre hombres y mujeres.

d. En locales comerciales de gran afluencia de público, tales como centros comerciales, supermercados, tiendas de departamentos, sucursales bancarias, parques de atracciones o de diversiones, museos y centros de convenciones, entre otros, habrán servicios sanitarios de uso público tanto para hombres como para mujeres, por lo menos uno en cada piso y accesibles a personas con discapacidad, y de acuerdo con lo indicado en la tabla 5.2. En este caso, lo indicado en la tabla 5.1 será válido para el personal permanente del local.

Al utilizar esta tabla, se deberá usar la situación más crítica, ya sea la que establezca el número de personas, o bien la que imponga el área del local.

e. En locales comerciales de gran afluencia de público, tales como centros comerciales, supermercados, tiendas de departamentos, sucursales bancarias, parques de atracciones o de diversiones, museos y centros de convenciones entre otros, se deberá contar con al menos una sala de lactancia materna de uso público y discrecional para que las madres puedan dar de mamar o extraer su leche. Esta será sala un espacio exclusivo para dicho propósito y deberá contar con un área mínima de 3m×3m, con ventilación e iluminación adecuada, natural de preferencia, así como condiciones higiénicas, privacidad y de seguridad apropiadas. Como mínimo la sala deberá contar con un lavatorio para el lavado de manos. El número de total de salas por edificación y sus dimensiones deberá estar en proporción razonada con el número total de mujeres en lactancia que se esperan en la edificación, partiendo de la experiencia de que no todas las madres las usarán de manera simultánea.

f. Se podrán instalar fuentes para beber en cada piso ocupado por personas y al menos una por cada ochenta (80) personas, las cuales deberán ser accesibles para personas con discapacidad. Estas fuentes deberán ser desinfectadas diariamente para reducir la posibilidad de contaminación bacteriana, así como ser inspeccionadas y mantenidas regularmente.

g. En todo edificio destinado a locales comerciales u oficinas, sea público o privado, debe haber al menos un servicio sanitario accesible en cada piso para el uso de hombres y otro para el uso de mujeres y, si estos son únicos, deberán ser accesibles a personas con discapacidad.

h. Se deberá instalar en cada piso una pileta para la limpieza del equipo utilizado en las labores de aseo.

5.1.3 ESTABLECIMIENTOS INDUSTRIALES

En establecimientos industriales, si el personal excede diez personas, habrán servicios sanitarios separados para hombres y mujeres, dotados de piezas sanitarias de acuerdo con lo siguiente:

a. Los inodoros estarán en proporción de uno por cada veinte (20) hombres o fracción de esta cifra, y uno por cada quince (15) mujeres o fracción de esta cifra presentes por turno de trabajo, cuando el total de trabajadores sea menor de cien (100). Cuando el número total de trabajadores exceda de este monto, deberá instalarse un inodoro adicional por cada veinticinco (25) hombres y uno por cada veinte (20) mujeres o fracción de esta cifra presentes por turno de trabajo.

b. Los mingitorios estarán en proporción de uno por cada treinta (30) hombres o fracción de esta cifra trabajando por turno.

c. Los lavatorios estarán en proporción de uno por cada diez (10) personas o fracción de esta cifra trabajando por turno, cuando el total de personas sea menor a cien. Cuando el número de personas sea mayor a cien (100) se deberá instalar un lavatorio adicional por cada quince (15) trabajadores.

d. En aquellos trabajos que por su especial naturaleza resulten peligrosos, sea porque los trabajadores están venenosos, infecciosos o irritantes, se deberán disponer duchas en la proporción de una por cada diez (10) trabajadores, o fracción de esta cifra, que cesen su trabajo simultáneamente.

e. En todo establecimiento industrial, sea público o privado, debe existir al menos un servicio sanitario accesible para el uso de hombres y otro para el uso de mujeres y, si estos son únicos, deberán ser accesibles a personas con discapacidad.

f. Se deberá instalar en cada piso una pileta para la limpieza del equipo utilizado en las labores de aseo.

Si el personal está compuesto por diez (10) personas o menos, se dispondrá de una sala sanitaria dotada de un mingitorio, un inodoro y un lavatorio. Esta sala sanitaria deberá ser accesible para personas con discapacidad.

En caso de que el número de trabajadores no esté especificado, se estimará basándose en la proporción de un trabajador de cada sexo por cada treinta metros cuadrados (30 m2) de área útil de piso de la edificación o local destinado a industria.

5.1.4 RESTAURANTES, SALAS DE BAILE, CAFETERÍAS, BARES Y SIMILARES

En locales de restaurantes, salas de baile, cafeterías, bares y similares con capacidad de atención hasta de diez (10) personas simultáneamente, dispondrán de al menos un cuarto de baño dotado de un inodoro y un lavatorio; este cuarto de baño deberá ser accesible para personas con discapacidad. Cuando la capacidad sobrepase las diez (10) personas, se dispondrán de servicios separados para hombres y mujeres de acuerdo a la tabla 5.3. Al menos dos (2) de estos servicios serán accesibles a personas con discapacidad, uno para hombres y otro para mujeres. Cuando en un local se le dé un cambio de uso, deberán realizarse las modificaciones necesarias para que se cumplan los requerimientos para el nuevo uso.

Para el personal de servicio se dispondrá de servicios sanitarios independientes de los del público, cuando el número de empleados presentes exceda de seis (6) personas. En tal caso, se dispondrá de servicios sanitarios de acuerdo con lo estipulado en la tabla 5.1. Al utilizar esta tabla, se deberá usar la situación más crítica, ya sea la que establezca el número de personas o bien la que imponga el área del local. Al menos uno de estos servicios sanitarios será accesible para personas con discapacidad.

En las áreas de preparación de alimentos, se deberá instalar el número adecuado de accesorios, según lo indique la autoridad sanitaria (Ministerio de Salud).

Se deberá disponer, en la cocina, de facilidades para el lavado de manos de los empleados. 5.1.5 SALAS DE ESPECTÁCULO, AUDITORIOS, ESTADIOS, TEMPLOS Y SIMILARES

En salas de espectáculos, como cines, teatros, auditorios y similares, así como en edificaciones deportivas, tales como estadios, arenas, hipódromos, plazas de toros y similares, se proveerán cuartos de baños para el público, separados para hombres y para mujeres, según lo indicado en la tabla 5.4. Como mínimo, deberán existir dos (2) cuartos de baño accesibles, uno para hombres y otro para mujeres, exclusivamente para personas con discapacidad.

Se deberán instalar fuentes para beber en los vestíbulos de cada cuarto de baño, nunca dentro del cuarto, de acuerdo con las siguientes proporciones:

a. Una fuente: 1-100 personas b. Dos fuentes: 101-300 personas c. Tres fuentes: 301-500 personas d. Mayor a 500: agregar una por cada 400 personas Al menos una de esas fuentes será accesible para personas con discapacidad. Estas fuentes deberán ser desinfectadas diariamente, para reducir la posibilidad de contaminación bacteriana, así como ser inspeccionadas y mantenidas regularmente.

Se deberán proveer, además, servicios sanitarios para los actores, jugadores y empleados, según el artículo 5.9.1.1 y la tabla 5.1 (utilizando el número de personas y no el área).

TABLA 5.4 NÚMERO DE PIEZAS SANITARIAS EN SALAS DE ESPECTÁCULO

En los templos religiosos, se deberán proveer servicios sanitarios separados por sexo y la cantidad de accesorios estará de acuerdo con las siguientes proporciones:

a. Inodoro: 1 por cada 150 hombres/75 mujeres.

b. Lavatorio: 1 por cada 300 hombres/150 mujeres.

c. Mingitorio: 1 por cada 75 hombres.

Como mínimo, deberán existir dos cuartos de baño accesibles para personas con discapacidad, uno para hombres y otro para mujeres.

Los templos religiosos deberán contar con al menos una sala de lactancia materna para que las madres, de manera discrecional, puedan dar de mamar o extraer su leche. Esta será un espacio exclusivo para dicho +n y deberá contar con un área mínima de 3m×3m, con ventilación e iluminación adecuada, así como condiciones higiénicas, de privacidad y de seguridad apropiadas. Como mínimo, la sala deberá contar con un lavatorio para el lavado de manos. El número total de salas y sus dimensiones deberá estar en proporción razonada con el número total de mujeres en lactancia que se esperan en el templo, partiendo de la experiencia de que no todas las madres las usarán de manera simultánea.

5.1.6 ESTACIONAMIENTOS Y ESTACIONES DE SERVICIO

En el caso de estacionamientos públicos, se proveerán servicios sanitarios independientes para hombres y mujeres a razón de un mingitorio, un inodoro y un lavatorio para hombres, y dos inodoros y un lavatorio para mujeres. Cada uno de esos servicios sanitarios deberá ser accesible para personas con discapacidad.

En las estaciones de servicio se deberán proveer de, al menos, tres servicios sanitarios. Uno de ellos será para los trabajadores y dos para uso del público, uno para mujeres y otro para hombres. Estos servicios contarán, cuando menos, con un inodoro y un lavatorio cada uno, y un mingitorio en el de hombres. Además, deberá proveerse una ducha accesible para los trabajadores.

Los servicios sanitarios de las estaciones de servicio deberán cumplir con lo establecido por el Minae en el Reglamento para la Regulación del Sistema de Almacenamiento y Comercialización de Hidrocarburos, según el decreto 30131-Minae.

5.1.7 CENTROS DE ENSEÑANZA

En los centros de enseñanza se proveerá para los estudiantes de servicios sanitarios separados para hombres y mujeres; la cantidad de accesorios por instalar estará de acuerdo con lo indicado en la tabla 5.5.

TABLA 5.5 NÚMERO DE PIEZAS SANITARIAS EN CENTROS Como mínimo, deberán existir dos cuartos de baño accesibles para personas con discapacidad en cada piso, uno para hombres y otro para mujeres.

Se dispondrán cuartos de baño para los maestros, profesores y demás empleados administrativos. Cuando el número de estos funcionarios sea menor a diez (10) personas, habrá por lo menos un servicio sanitario dotado de un lavatorio y un inodoro. Este servicio sanitario deberá ser accesible para personas con discapacidad. Cuando el personal docente sobrepase de diez (10) personas, se aplicará lo dispuesto en la tabla 5.6. Al menos dos de estos servicios serán accesibles para personas con discapacidad, uno para hombres y otro para mujeres.

TABLA 5.6 NÚMERO DE PIEZAS SANITARIAS EN CENTROS EDUCATIVOS PARA PROFESORES

En residencias estudiantiles y similares se utilizarán las siguientes proporciones: para hombres, un inodoro cada diez (10) hombres, un lavatorio y una ducha por cada ocho (8) hombres, y un mingitorio por cada quince (15); para mujeres, un inodoro y una ducha por cada ocho (8) mujeres, un lavatorio cada diez (10) mujeres. Para hombres, al menos un inodoro, un lavatorio, una ducha y un mingitorio deberán ser accesibles para personas con discapacidad. Para mujeres, al menos un inodoro, un lavatorio y una ducha deberán ser accesibles a personas con discapacidad.

Los centros de enseñanza de educación superior deberán contar con al menos una sala de lactancia materna para que las estudiantes que sean madres, de manera discrecional, puedan dar de mamar, extraer su leche y dejarla almacenada. Este será un espacio exclusivo para dicho +n y deberá contar con un área mínima de 3m×3m, con ventilación e iluminación adecuada, así como condiciones higiénicas, de privacidad y de seguridad apropiadas. Como mínimo, la sala deberá contar con un lavatorio para el lavado de manos.

El número de total de salas y sus dimensiones deberá estar en proporción razonada con el número total estimado de estudiantes mujeres en lactancia en el centro de enseñanza, partiendo de la deberá también guardar proporción razonada con el número de edificaciones que componen el centro de enseñanza.

Se deberá proveer de pilas en cada piso de la institución para el aseo de los equipos de limpieza.

Centros de preescolar y escuelas. Las piezas sanitarias serán de diseño y de dimensiones adecuadas para ser usadas por los escolares y se instalarán a una altura apropiada. La cantidad de accesorios sanitarios se podrá seleccionar de la tabla 5.7.

En centros de preescolar y escuelas, los lavamanos deberán instalarse de manera que su borde superior no quede a una altura mayor a sesenta y cinco centímetros (65 cm) del nivel del piso terminado.

TABLA 5.7 NÚMERO DE PIEZAS SANITARIAS EN CENTROS DE PREESCOLAR

Cuando no se disponga de baños exclusivos para cada dormitorio, el establecimiento deberá cumplir con lo siguiente:

a. Un lavatorio con agua fría y desagüe en cada dormitorio.

b. Un cuarto de baño y un lavatorio por cada tres dormitorios o por cada cinco camas; deberán ser accesibles a personas con discapacidad.

c. Un inodoro accesible e independiente por cada tres dormitorios o por cada cinco camas y, en todo caso, uno en cada piso, como mínimo.

d. Los servicios sanitarios no deberán encontrarse a más de cuarenta metros (40,0 m) del cuarto más alejado horizontalmente.

e. Una fuente de beber accesible por cada setenta y cinco (75) huéspedes, mínimo una en cada piso, instalada en el vestíbulo; deberán ser desinfectadas diariamente para reducir la posibilidad de contaminación bacteriana, así como ser inspeccionadas y mantenidas regularmente.

f. Todos los hoteles o afines deberán contar con una pileta de servicio por cada veinte dormitorios, con al menos una en cada piso.

Los servicios sanitarios destinados al público que concurre al establecimiento y los del personal deberán ser independientes. El número de piezas sanitarias se estimará con base en la tabla 5.2. Como mínimo, deberá existir dos cuartos de baño accesibles destinados al público, uno para hombres y otro para mujeres.

5.1.9 INSTALACIONES DEPORTIVAS Y BAÑOS PÚBLICOS

Se proveerán de servicios sanitarios para hombres y para mujeres de acuerdo con lo siguiente:

a. Hombres: un inodoro por cada veinte (20) hombres, un lavatorio por cada quince (15) hombres; una ducha por cada cinco (5) hombres y un mingitorio por cada veinticinco (25) hombres. Al menos una pieza sanitaria de cada tipo deberá ser accesible para personas con discapacidad.

b. Mujeres: un inodoro y un lavatorio por cada quince (15) mujeres y una ducha por cada cinco (5) mujeres. Al menos una pieza sanitaria de cada tipo deberá ser accesible para personas con discapacidad.

Piscinas. Para la estimación del número de bañistas en piscinas, se considerará una persona por cada metro y medio cuadrado (1,5 m2) de superficie líquida de la piscina.

En el acceso de cada piscina se deberá ubicar al menos una ducha accesible para el lavado de los bañistas antes de entrar en ella.

Fuentes para beber. Se podrán instalar fuera de los servicios sanitarios, en proporción de una por cada doscientas (200) personas. Esta fuente deberá ser accesible para personas con discapacidad. Las fuentes para beber deberán ser desinfectadas diariamente, para reducir la posibilidad de contaminación bacteriana, así como ser inspeccionadas y mantenidas regularmente.

5.1.10 OBRAS EN CONSTRUCCIÓN

Toda obra en construcción deberá contar con un sistema adecuado de desecho de las excretas, con capacidad proporcional al número de trabajadores en la obra, y deberá contar con un servicio de agua potable para su aseo.

Se deberán instalar inodoros o letrinas provisionales, a razón de uno por cada ocho (8) trabajadores.

5.1.11 HOSPITALES, CLÍNICAS Y CENTROS DE ATENCIÓN

Las edificaciones destinadas a instalaciones de salud, que se indican a continuación, serán dotadas de servicios sanitarios y de piezas sanitarias del tipo y del número mínimo que se anota en cada caso. Como mínimo, deberá existir dos cuartos de baño accesibles para personas con discapacidad en cada piso, uno para hombres y otro para mujeres.

5.1.11.1 CENTROS CON HOSPITALIZACIÓN

En centros de salud donde se cuente con servicios sanitarios de uso privado para cada habitación, se instalará un inodoro, una ducha y un lavamanos.

En centros donde las habitaciones no cuenten con cuarto de baño, o en salas generales de hospitalización y para uso de los hospitalizados, se proveerá de:

a. Servicios sanitarios separados para hombres y mujeres, a nivel de cada piso destinado a hospitalización.

b. En cada una de los servicios sanitarios requeridos se instalará un inodoro, un lavatorio, un mingitorio y una ducha al menos por cada diez (10) pacientes, además de una pila de aseo por cada diez (10) pacientes.

En los servicios sanitarios para hombres se podrá sustituir inodoros por mingitorios, pero en tal proporción que el número de mingitorios no sea mayor que la tercera parte del número total de inodoros requeridos.

Para uso de los visitantes y sus acompañantes, en las salas de espera se proveerá como mínimo de un cuarto de baño para hombres y uno para mujeres. En cada una de estas se instalará un inodoro y un lavamanos como mínimo. Además, se instalará una fuente de beber en cada nivel, ubicada fuera de los servicios sanitarios, la cual deberá ser accesible a personas con discapacidad. Esta fuente deberá ser desinfectada diariamente, para reducir la posibilidad de contaminación bacteriana, así como ser inspeccionada y mantenida regularmente.

El tipo y número mínimo de piezas sanitarias que debe ser instalado en salas adyacentes a quirófanos, maternidad, morgues y demás servicios del centro médico, corresponderán a las normas específicas que al respecto dicte la autoridad sanitaria competente.

Para uso del personal residente, de empleados y trabajadores del centro asistencial, se proveerán adicionalmente servicios sanitarios adecuadamente ubicados, tanto para hombres como para mujeres, y en ellos se instalarán piezas sanitarias del tipo y número que, como mínimo, se señalan en la tabla 5.1. Al utilizar esta tabla se deberá usar la situación más crítica, ya sea la que establezca el número de personas o bien la que imponga el área del local. Como mínimo, deberán existir dos cuartos de baño accesibles a personas con discapacidad en cada piso, uno para hombres y otro para mujeres.

Cada piso deberá contar con una pileta de aseo, al menos una por piso.

5.1.11.2 CENTROS CON CONSULTA EXTERNA

En cada consultorio se instalará un cuarto de baño con un lavamanos y un inodoro, cuando sea requerido.

En las salas de espera de los consultorios y para uso de los acompañantes de los pacientes, se instalará un cuarto de baño accesible para hombres y uno para mujeres, y en cada uno se instalará como mínimo un lavamanos y un inodoro.

Para uso del personal residente, de empleados y trabajadores del centro asistencial, se proveerán adicionalmente servicios sanitarios adecuadamente ubicados, tanto para hombres como para mujeres, y en ellos se instalarán piezas sanitarias del tipo y número que como mínimo se señalarán en la tabla 5.1. Al utilizar esta tabla, se deberá usar la situación más crítica, ya sea la que establezca el número de personas o bien la que imponga el área del local. Como mínimo deberá existir dos (2) cuartos de baño accesibles a personas con discapacidad en cada piso, uno para hombres y otro para mujeres.

5.1.11.3 CLÍNICAS Y CONSULTORIOS DENTALES

Cada consultorio dental único deberá proveer un cuarto de baño, accesible para personas con discapacidad, para uso de pacientes y sus acompañantes, en el que se instalará un lavamanos y un inodoro como mínimo.

En cada consultorio dental se instalará, como mínimo, un lavamanos directamente accesible desde la unidad dental.

Las clínicas dentales donde funcionen simultáneamente varios consultorios dentales podrán ser dotadas de servicios sanitarios comunes a ellas, separados para hombres y para mujeres. En cada uno de ellos se instalará un inodoro y un lavamanos, al menos. Como mínimo, deberá existir dos cuartos de baño accesibles a personas con discapacidad en cada piso, uno para hombres y otro para mujeres.

5.1.12 CÁRCELES Y CENTROS CORRECCIONALES

En caso de existir celdas individuales, se instalará un inodoro y un lavamanos en cada celda.

En caso de celdas comunes, la cantidad mínima de accesorios por instalar en los servicios sanitarios deberá cumplir con lo siguiente:

. Un inodoro por cada veinte (20) hombres.

. Un mingitorio por cada cincuenta (50) hombres.

. Un inodoro por cada quince (15) mujeres.

. Se instalará un lavamanos por cada diez (10) privados de libertad.

. Se instalará una ducha por cada cincuenta (50) privados de libertad.

. Se instalará una fuente de beber en cada piso, ubicada fuera de los servicios sanitarios; estas fuentes deberán ser desinfectadas diariamente para reducir la posibilidad de contaminación bacteriana, así como ser inspeccionadas y mantenidas regularmente.

. Se instalará una pila de servicio en cada piso.

Para uso del personal residente, empleados y trabajadores, se proveerán adicionalmente servicios sanitarios separados para hombres y para mujeres, de acuerdo con lo establecido en la tabla 5.1. Al utilizar esta tabla se deberá usar la situación más crítica, ya sea la que establezca el número de personas o bien la que imponga el área del local.

5.2 ESPECIFICACIONES DE LAS PIEZAS SANITARIAS 5.2.1 NORMAS GENERALES

Las piezas sanitarias deberán estar construidas de materiales duros, resistentes e impermeables, tales como porcelana, losa vitrificada, acero inoxidable, o cualquier otro con características similares a los mencionados. Las superficies de las piezas deberán ser lisas y carecer de defectos interiores o exteriores.

Accesorios de bajo consumo. Con el fin de incluir prácticas sobre el uso racional de los recursos naturales, se recomienda el uso de accesorios que manejen caudales menores a los accesorios tradicionales. Los accesorios podrán ser identificados al poseer un sello de eficiencia dado por alguna organización mundial, por ejemplo la Usepa (Agencia de Protección Ambiental de Estados Unidos, por sus siglas en inglés).

Conexión cruzada. Las piezas sanitarias deberán ser instaladas de modo que no presenten conexiones cruzadas que puedan contaminar el agua potable.

Para impedir conexiones cruzadas, el espacio libre entre la boca del grifo de alimentación y el nivel de rebose en las piezas sanitarias deberá estar de acuerdo con la tabla 5.8.

TABLA 5.8 ESPACIO LIBRE MÍNIMO PARA IMPEDIR UNA CONEXIÓN CRUZADA 5.2.1.1 INSTALACIÓN

En las piezas sanitarias que tengan suministro de agua fría y caliente, el agua fría deberá entregarse por la derecha y el agua caliente por la izquierda, mirando la pieza de frente.

En el caso de una única llave de regulación, se aplicará el sentido de giro según sea fría o caliente.

Las piezas sanitarias deberán instalarse en ambientes adecuados, previendo los espacios mínimos necesarios para su adecuado uso, limpieza, reparación, inspección y ventilación, según lo especificado en la sección 5.3.

Los accesorios conectados mediante unión de tope deberán tener un panel de acceso o un espacio útil de al menos treinta centímetros (0,30 m) en su menor dimensión. Donde sea práctico, todos los tubos provenientes de los accesorios deben estar cerca de las paredes.

Toda pieza sanitaria deberá estar dotada de su correspondiente sifón para el sello de agua. El sello de agua deberá tener una altura de al menos cinco centímetros (0,05 m) como mínimo.

Los inodoros, bidés y piezas sanitarias similares colocadas sobre el piso deberán estar +jadas con tornillos, pernos o por algún otro sistema que permita su desmontaje. Se instalarán sobre un accesorio adecuado (por ejemplo: brida y anillo o sello de cera).

Pieza Espacio libre (mm) Las piezas sanitarias de pared se fijarán por medio de soportes metálicos de forma que ningún esfuerzo sea transmitido a las tuberías y conexiones.

Los pernos o tornillos deberán ser de cobre, latón u otro material resistente a la corrosión.

Reflujo. Los tubos de abasto o los accesorios sanitarios deberán ser instalados para prevenir cualquier reflujo.

Toda pieza sanitaria construida en obra deberá recubrirse con material impermeable vitrificado y con todas las aristas interiores y exteriores redondeadas.

Accesorios prohibidos. No se permitirá la instalación, en los edificios para uso humano, de inodoros de tipo seco o químico.

5.2.2 INODOROS

Los inodoros con tanque deberán cumplir con los siguientes requisitos:

a. En el tubo de entrada de agua al tanque habrá una válvula de paso.

b. Los tanques tendrán capacidad suficiente para asegurar la limpieza completa de la pieza.

c. El mecanismo de accionamiento funcionará en forma tal que evite la pérdida o desperdicio de agua, reponga el sello de agua de la pieza e impida conexiones cruzadas.

d. Los inodoros con tanque deben tener la capacidad de descargar, si se produce algún desbordamiento, dentro de él mismo.

Los inodoros con válvula semiautomática deberán cumplir con los siguientes requisitos:

a. Cada inodoro estará dotado de su correspondiente válvula de paso instalada cerca del mismo, en un lugar de fácil acceso para su reparación.

b. La válvula semiautomática deberá permitir el paso del agua a un caudal y presión suficientes, de acuerdo con las recomendaciones del fabricante, para descargar y lavar el inodoro, y para reponer el sello de agua en cada operación.

c. Sólo podrán instalarse cuando se asegure que en el sistema de alimentación se mantendrá la presión y caudal mínimos requeridos.

d. La válvula semiautomática de descarga será ajustable, con el fin de que se pueda regular el gasto de descarga y la presión de trabajo.

e. La tubería ramal de alimentación de varios inodoros con válvula semiautomática de descarga estará dotada de un amortiguador para absorber los efectos del golpe de ariete.

Los asientos y las tapas de los inodoros serán de material impermeable, liso y de fácil limpieza. Los inodoros de uso público serán de tipo alargado y el asiento tendrá la parte frontal abierta.

En instituciones como jardín de infantes, preescolar y otros lugares similares donde las piezas sanitarias servirán a personas menores de siete años, las piezas sanitarias deberán tener una altura adecuada para dichas personas. Para los inodoros, se recomiendan las alturas indicadas en la tabla 5.9.

TABLA 5.9 DIMENSIONES PARA INODOROS OPERADOS POR PERSONAS MENORES DE 7 AÑOS

Para lograr un funcionamiento adecuado de los inodoros se deberán seguir las siguientes recomendaciones:

a. Los inodoros deberán contar con una tubería de ventilación, la cual ayuda en la descarga libre de los desechos. Esta tubería deberá ser de al menos treinta y ocho milímetros (0,038 m) de diámetro.

b. La tubería de ventilación deberá ubicarse a una distancia de al menos treinta y tres centímetros (0,33 m) de la salida del inodoro. En caso de que esta no se pueda ubicar cercana al inodoro, esta podrá ubicarse a una distancia no mayor de tres metros (3,0 m) de la salida del inodoro.

c. En el caso de inodoros que descargan al piso, la altura entre la salida del inodoro y la tubería de descarga deberá ser tal que evite turbulencia a la hora de la descarga y, además, que permita el desarrollo de una velocidad adecuada de descarga, la cual no debe ser muy alta, ya que puede provocar sifonaje. La distancia entre el centro del codo sanitario y el nivel del piso terminado deberá estar en el rango de veinticinco a sesenta centímetros (0,25 - 0,60 m).

d. La pendiente de la tubería de descarga deberá ser de un 1,5%, permitiendo una variación máxima de ±0,5%, con el +n de lograr un correcto acarreo de los sólidos.

e. Los materiales necesarios para un correcto montaje del inodoro son: la brida plástica, los pernos de anclaje y el empaque de cera. No se recomienda el uso de cemento para fijar la taza al piso.

f. Se debe dejar un espacio de al menos un centímetro (0,01 m) entre el tanque del inodoro y la pared, por lo que es importante la correcta ubicación del tubo de desagüe con respecto al nivel de pared terminada, según las distancia que indican los fabricantes.

5.2.3 MINGITORIOS

Los mingitorios o urinarios deberán cumplir con los siguientes requisitos:

a. Estar provistos de un sistema adecuado que permita el lavado de la pieza sanitaria, pudiendo ser un tanque de descarga automático para uno o más mingitorios, válvulas semiautomáticas individuales u otro sistema.

b. Los mingitorios provistos de válvulas semiautomáticas deberán cumplir con las mismas especificaciones para los inodoros con fluxómetro.

c. Si se utilizan mingitorios que funcionan sin agua, estos deben estar provistos de los medios apropiados para que se impida la entrada de gases al cuarto de baño donde estén ubicados, producto del proceso químico al que están sujetos. Este tipo de mingitorios deben contar con la debida trampa, ya sea por sello o por funcionamiento hidráulico de los dispositivos de salida, lo cual puede realizarse con la aplicación de aceites, geles especiales y al utilizar diafragmas o dispositivos de látex u otros materiales semejantes.

5.2.4 DUCHAS

Los espacios destinados para duchas deberán cumplir con los siguientes requisitos:

a. Se ubicarán en forma tal que el agua caiga sobre un área libre.

b. El piso deberá ser de material impermeable y antideslizante en seco y en mojado, con una pendiente mínima del dos por ciento (2%) y una máxima del cuatro por ciento (4%) hacia el desagüe. Se podrá colocar un pequeño muro o grada que impida el escurrimiento de agua a otras partes del baño. El dique o grada no será menor a cinco centímetros (0,05 m) y no mayor a veintitrés centímetros (0,23 m). En el caso de que no se utilice un muro o grada con el objetivo de facilitar la accesibilidad, el piso o el plato de la ducha deberá estar a ras con el piso circundante del cuarto de baño y la pendiente de los planos inclinados que se formen para facilitar el desagüe será del 2%.

c. El desagüe estará dotado de un sifón y provisto de una rejilla removible de material inoxidable. Los orificios de la rejilla deberán ser tales que permitan evacuar rápidamente el caudal de servicio de cada ducha, sin acumular agua.

d. Los pisos de las duchas para uso público tendrán la pendiente dispuesta en tal forma que el agua servida de cada ducha no pase por las áreas destinadas a otros bañistas.

e. Todas las aristas en el piso y esquinas de muros serán redondeadas.

f. Los muros irán acabados con material impermeable hasta una altura mínima de un metro y medio (1,5 m).

g. Las bañeras del tipo empotradas o semiempotradas deberán tener una junta impermeable entre la pared y la pieza sanitaria.

5.2.5 FREGADEROS Y LAVAMANOS

Las pilas para lavar ropa, los fregaderos y los lavamanos deberán proveerse de dispositivos adecuados que impidan el paso de sólidos al sistema de desagüe y su sifón deberá ser fácilmente registrable para su limpieza.

La capacidad y las dimensiones mínimas del lavamanos serán: largo de 33 cm, ancho de 23 cm, profundidad de 13 cm y deberán estar de acuerdo con el uso propuesto a juicio de la autoridad sanitaria competente.

5.2.6 SUMIDEROS

Los sumideros de piso deberán cumplir con los siguientes requisitos:

a. El sello de agua correspondiente tendrá una altura mínima de siete centímetros y medio (0,075 m).

b. Estarán provistos de tapas removibles, perforadas o ranuradas. El área libre de la tapa será de por lo menos el 66% del área del tubo de descarga correspondiente.

Las dimensiones de la tapa y de su tubo de descarga serán tales que aseguren el buen funcionamiento del aparato.

Los sumideros de piso deberán ser instalados en los siguientes lugares:

a. En servicios sanitarios que tengan dos o más inodoros, o un mingitorio y un inodoro, excepto en viviendas unifamiliares. El piso deberá tener una inclinación hacia el sumidero.

b. Cocinas comerciales.

c. En cuartos de lavado de edificios comerciales o en áreas comunes de lavado en los edificios multifamiliares.

d. En áreas de almacenamiento de alimentos, como cuartos de almacenaje, cámaras frigoríficas accesibles y similares; estos drenajes deberán ser indirectos; un drenaje separado saldrá de cada área y será conectado indirectamente al drenaje sanitario del edificio.

En el caso de accesorios como estanques ornamentales, acuarios, piscinas, fuentes ornamentales, dispensadores comerciales de agua y construcciones similares deben ser protegidas contra reflujo, en el caso de que sean alimentadas directamente del sistema de agua potable.

Los accesorios provistos con dispositivos de rebalse deberán cumplir con estos requisitos:

a. La capacidad de rebose deberá ser suficiente para descargar el gasto máximo de alimentación de la pieza.

b. El dispositivo de rebose deberá ser tal que el agua no quede estancada en él.

c. El rebose desaguará entre el orificio de descarga y el sifón de la pieza sanitaria correspondiente. En el caso de los tubos de rebose de estanques de inodoros y urinarios, estos podrán descargar en el inodoro o en el urinario respectivo.

5.2.7 FUENTES PARA BEBER

Las fuentes para beber con enfriamiento propio, o sin él, serán de diseño específico para el uso propuesto y deberán cumplir con los siguientes requisitos:

a. Estar provistos de medios para regular la presión de descarga.

b. Tener una llave de cierre automático de accionamiento manual o de pie.

c. El ori+cio de salida del chorro deberá estar protegido, de manera que se impida el contacto directo con los labios.

d. El ángulo de salida del chorro deberá estar inclinado entre 60 y 45 grados aproximadamente.

Las fuentes para beber no podrían instalarse dentro de los cuartos de baño y deberán ser desinfectadas diariamente, para reducir la posibilidad de contaminación bacteriana, así como ser inspeccionadas y mantenidas regularmente.

5.2.8 BIDÉS

Cuando se desee instalar un bidé en un cuarto de baño de uso privado, se deberá cumplir con los siguientes requisitos:

a. Las válvulas y las demás conexiones de alimentación de la pieza sanitaria deberán permitir el paso del agua a caudal adecuado, para lavar la superficie interior de la pieza en su totalidad, desaguar las aguas residuales y reponer el sello de agua en cada operación.

b. El diseño de la pieza deberá garantizar el lavado de la totalidad de la superficie interior de la misma, después de cada operación.

c. El bidé podrá ser sustituido por una ducha de operación manual. La ducha se instalará cerca del inodoro, se dotará de válvulas de paso y de manguera flexible y se dotará de piezas de sostén y sujeción para evitar su permanencia en el piso y se ubicará a no menos de 30 centímetros por encima del nivel desbordamiento del inodoro.

d. Deberá contar con un sifón o trampa de agua.

5.3 ESPECIFICACIONES DE LOS CUARTOS DE BAÑO

Todos los muebles sanitarios y sus accesorios deberán ser instalados guardando su correcto espaciamiento y permitiendo su acceso y uso adecuado. La figura 5.1 indica las dimensiones mínimas sugeridas para la instalación de piezas sanitarias.

En todos los servicios sanitarios para uso público se proveerán sumideros de piso que faciliten su adecuada higienización.

El área mínima de los cuartos de baño en viviendas unifamiliares y multifamiliares (incluyen un lavatorio, un inodoro y una ducha) será de dos y medio metros cuadrados (2,5 m2) de área y un metro (1,0 m) de ancho.

Se deberá cumplir con lo indicado en el Reglamento de Construcciones, según el tipo de edificación. En caso de que el Reglamento de Construcciones no dé indicaciones específicas para un tipo de edificación, se podrá contemplar lo siguiente:

a. La altura mínima de los cuartos de baño de piso a cielo raso será de dos metros cuarenta centímetros (2,40 m), siempre que la cubierta del techo o el cielo raso, si lo hubiere, sean de material aislante o reflectivo del calor.

b. Si el material del techo no es aislante, la altura debe aumentarse a un mínimo de dos metros sesenta centímetros (2,60 m). Se podrá aceptar una altura mínima de dos metros veinticinco centímetros (2,25 m), siempre y cuando el área de ventilación se aumente en un 15%.

Los cuartos de baño deberán tener iluminación y ventilación por medio de ventanas, linternillas o tragaluces, que darán directamente a patios o al espacio público. También se podrá proveer de ventilación por medio mecánico, siempre y cuando se cumpla con las normas de la autoridad sanitaria competente.

Los requerimientos de los cuartos de baño con respecto a iluminación, ventilación natural, dimensiones de puertas y ventanas, y otros detalles arquitectónicos deberán cumplir con las exigencias del Reglamento de Construcciones.

5.3.1 VENTILACIÓN ARTIFICIAL

Los servicios sanitarios podrán ser ventilados artificialmente y deberán cumplir con lo establecido en el presente Código.

Todo sistema de ventilación artificial o mecánica de un local se fundamentará en la inyección de aire fresco y no contaminado al interior del local de una edificación y permitirá la salida de aire viciado al exterior; o bien, en la extracción del aire viciado del local permitirá, a la vez, la entrada de una cantidad de aire fresco y no contaminado desde el exterior.

Para cualquier sistema de ventilación por desarrollar, las tomas de aire fresco y sin contaminación deberán hacerse en forma directa desde el exterior de la edificación correspondiente.

La velocidad del aire introducido en recintos, con fines de ventilación artificial, no debe sobrepasar en más de un diez por ciento (10%) los valores anotados en la tabla 5.10.

El aire viciado de cualquier sistema de ventilación artificial deberá descargarse directamente al exterior de la edificación y en tal forma que no pueda regresar, ni afectar en forma alguna las edificaciones vecinas.

El número de cambios de aire por hora necesarios para la ventilación artificial de un cuarto de baño se determinará de acuerdo con el tipo de edificación y con su uso, de acuerdo con lo anotado en la tabla 5.11.

Las servicios sanitarios en edificaciones de hasta tres pisos de altura podrán ser ventiladas artificialmente por extracción, mediante ventiladores individuales instalados en cada cuarto de baño, provista de compuertas con contraflujo y conectados a ductos destinados exclusivamente para la ventilación del cuarto de baño.

Los ductos a que se refiere el artículo anterior deberán tener sección suficiente de manera que si todos los ventiladores se encuentran funcionando, la velocidad del aire en el ducto no sea mayor a cinco metros por segundo (5 m/s).

Las servicios sanitarios de edificaciones de cualquier número de pisos podrán ser ventiladas artificialmente mediante extracción del aire de las mismas por un ventilador instalado en la parte más alta de un ducto vertical de ventilación, destinado exclusivamente a dicha finalidad y común para todas las servicios sanitarios.

Las rejillas de extracción deberán estar dotadas de mecanismos de regulación individuales, con el fin de permitir regular la cantidad de aire por extraer de cada cuarto de baño.

Las puertas de acceso de los servicios sanitarios ventilados artificialmente de acuerdo con lo especificado en los artículos anteriores, deberán estar provistas de una abertura u otro sistema que permita la entrada de aire fresco. El área mínima de esta abertura se estimará con la siguiente ecuación:

Donde, Q: caudal de aire extraído del cuarto de baño (m3/s) V: velocidad del aire que entra por la rejilla.

Para locales comerciales y oficinas, esta presenta un rango de setenta a cien centímetros por segundo (0,7-1,0 m/s). Para edificaciones industriales, el rango es de doscientos cincuenta a cuatrocientos centímetros por segundo (2,5-4,0 m/s).

6 SISTEMAS DE AGUA FRÍA Y AGUA CALIENTE 6.1 NORMAS GENERALES

La ejecución de la conexión domiciliaria estará a cargo de la autoridad administrativa del servicio de agua potable.

El sistema de distribución de agua potable de las edificaciones deberá diseñarse de acuerdo con las condiciones bajo las que el abastecimiento de agua público prestará servicio.

La simbología básica que se utilizará en los planos de instalaciones sanitarias e hidráulicas será la indicada en la +gura 6.1.

a. No se permitirán conexiones directas entre las tuberías de la red pública y bombas u otros aparatos mecánicos de elevación de presión.

b. El sistema de distribución de agua potable en un edificio no deberá estar conectado, directa ni indirectamente, con sistema alguno de agua no potable.

c. Queda terminantemente prohibido realizar conexiones directas o indirectas entre el abastecimiento público de agua y el abastecimiento privado o el de emergencia.

El sistema de alimentación y distribución de agua estará dotado de válvulas adecuadas a la presión existente, según se muestra en las figuras 6.2 y 6.3, y como mínimo en los siguientes puntos:

a. Una en cada conexión al servicio público después del medidor correspondiente.

b. Una en cada piso, una para cada sección independiente en edificios de apartamentos u oficinas, o para cada sección de piso que no tenga comunicación horizontal.

c. Una en cada baño colectivo o público, en edificios de oficinas públicas o comerciales.

Para evitar posibles reflujos de agua, es recomendable colocar una válvula de retención después del medidor. Además, deberán colocarse válvulas de retención en los puntos indicados en la figura 6.2.

Cuando el abastecimiento de agua público garantice servicio continuo a una presión y caudal suficientes, el sistema de distribución podrá servirse directamente de la red pública, según se muestra en la figura 6.2a.

Cuando el abastecimiento de agua público no garantice servicio continuo, se utilizará alguno de los siguientes sistemas indirectos:

a. Tanque elevado (+guras 6.2b y 6.3a) b. Tanque de captación, equipo de bombeo y tanque hidroneumático (figuras 6.2e y 6.3d) c. Cisterna, equipo de bombeo y tanque elevado (+guras 6.2c, 6.3b, 6.3c, 6.3e y 6.3f )

Cuando el abastecimiento público de agua no garantice presión suficiente, el sistema de distribución de la edificación deberá utilizar alguno de los sistemas estipulados en los incisos b y c del artículo anterior.

En edificios de gran altura, el sistema de distribución deberá proyectarse en grupos de pisos, de manera que no sobrepasen las presiones previstas en la sección 6.3.1 (ver figura 6.3).

6.2 MATERIALES PARA TUBERÍAS, VÁLVULAS Y ACCESORIOS

En las obras para el abastecimiento y distribución de agua deberán utilizarse únicamente tuberías y accesorios de los siguientes materiales:

a. PVC b. Hierro galvanizado c. Cobre d. Polietileno de alta densidad e. CPVC f. Polipropileno g. Hierro negro Indicaciones:

. Las tuberías de CPVC se pueden usar tanto para distribución de agua fría como caliente.

. En las tuberías de cobre se permite el uso de tubería tipo K, L o M. Se puede utilizar tubería M para distribución de agua, si el tubo se encuentra sobre el piso o sobre el edificio, o enterrado en un sitio que no tenga ninguna estructura.

. Las válvulas de un tamaño menor o igual a 51 mm (2 pulg.) deberán ser de bronce u otro material aprobado. Para tamaños mayores a 51 mm, el cuerpo de la válvula deberá ser de hierro fundido o de bronce.

. Las piezas de conexión por utilizarse deberán ser preferentemente del mismo material de las tuberías que unan y de características acordes.

. La conexión entre tuberías de materiales diferentes y entre los cuales no se produzca acción galvánica se hará directamente o utilizando piezas de conexión adaptadoras o convertidores adecuadas.

. Las correspondientes juntas podrán ser soldadas, electrofusionadas, termofusionadas, roscadas, a presión, de brida o mecánicas, o la combinación de estas, dependiendo en cada caso de los tipos de tuberías por unir y de sus características.

. Las juntas de las tuberías deberán estar de acuerdo con su clase; podrán ser de los siguientes tipos: espiga y campana, de brida, de rosca, soldados y de conexión, mediante aros de goma, mecánicas y a comprensión.

. Cuando se desee utilizar tuberías de otros materiales a los señalados en la presente sección, se podrá realizar de acuerdo con el análisis técnico realizado por el profesional responsable del diseño o el profesional responsable de la ejecución de la obra. Se deberá tener presentes las objeciones de la autoridad sanitaria u otras instituciones del Estado que deben realizar inspección del proyecto.

Las tuberías deberán cumplir con los siguientes requisitos generales:

a. Material homogéneo b. Sección transversal circular de dimensiones normalizadas c. Espesor de pared uniforme d. Dimensiones, pesos y espesores de acuerdo con las especificaciones correspondientes a las condiciones de operación respectiva e. Carecer de defectos tales como grietas, abolladuras y deformaciones

Normativa técnica.

Para todos los tipos de tuberías, conexiones y accesorios, con la salvedad de las fabricadas en PVC y CPCV, mientras no estén vigentes en el país normas técnicas industriales, se considerarán de calidad satisfactoria si cumplen con las especificaciones más recientes de entidades cali+cadas, tales como la American Society for Testing and Materials (ASTM), la American Water Works Association (AWWA), o la International Organization for Standarization (ISO).

Normativa PVC.

En el caso de tuberías de PVC y CPVC, las tuberías y sus accesorios deberán cumplir con las siguientes normas:

ASTM D - 2241 para tuberías de agua potable ASTM D 1785 para tuberías de agua potable ASTM D 2466 accesorios para tuberías de agua potable ASTM D 2464 accesorios para tuberías de agua potable ASTM D 2846 para tuberías y accesorios de CPVC para agua caliente (DWG) ASTM D- 3350 para tuberías y accesorios de polietileno (PE) 6.3 NORMAS PARA EL DIMENSIONAMIENTO DE TUBERÍAS DE DISTRIBUCIÓN 6.3.1 PRESIONES Y GASTOS MÍNIMOS

La presión mínima en los nodos del sistema de distribución deberá permitir el funcionamiento adecuado de las piezas sanitarias correspondientes. La tabla 6.1 indica las presiones mínimas recomendadas para la operación de varios aparatos sanitarios. En ningún caso la presión a la entrada de las piezas sanitarias será menor de dos metros de columna de agua (2 mca). Si la presión máxima en los puntos de alimentación de las piezas sanitarias es mayor a cuarenta metros columna de agua (40 mca), el sistema deberá dividirse en zonas de presión, o instalar válvulas reductoras de presión.

La presión de servicio después del medidor deberá ser mayor a diez metros de columna de agua (10 mca).

(1) Diámetro interno mínimo de tubería de alimentación. En el caso de inodoros y lavatorios, este diámetro es del ramal de alimentación hasta la llave de paso.

(2) Presión mínima a la entrada del accesorio en metros de columna (o cabeza) de agua.

(3) La presión mínima depende del tipo de válvula semiautomática.

(4) Caudales en función de las unidades de accesorio. Estos caudales son para dimensionar tanto las tuberías que conducen solamente agua fría como aquellas que conducen agua fría y el caudal que deba calentarse. En el caso de que se trate de accesorios con suministro independiente para agua fría y agua caliente, se podrá asumir que por cada una de ellas circularán las tres cuartas partes de los caudales descritos en la presente tabla.

6.3.2 VELOCIDADES DE FLUJO

Para el dimensionamiento de las tuberías de distribución se recomienda una velocidad mínima de sesenta centímetros por segundo (0,60 m/s) para evitar la sedimentación de partículas, y una velocidad máxima de dos metros por segundo (2,00 m/s) para evitar ruido excesivo en las tuberías y golpes de ariete.

Para evitar pérdidas de carga excesivas se recomienda mantener las velocidades máximas según la expresión:

Donde: V es la velocidad en metros por segundo y es la raíz cuadrada del diámetro interno de la tubería en metros y en ningún caso mayor a dos metros por segundo (2,0 m/s). Las velocidades recomendadas resultan en pérdidas por fricción que oscilan entre diez y veinte centímetros de columna de agua (0,10 y 0,20 mca) por metro lineal de tubería.

La tabla 6.2 indica las velocidades y caudales máximos recomendados de acuerdo con los criterios anteriores, para tuberías de hierro galvanizado, CPCV y de PVC.

Nota:

(1) Estimado para tubería SDR 17 (SDR 13,5 en 12 mm).

(2) Hierro galvanizado.

(3) Pérdida de carga por unidad de longitud de tubería estimada según la sección 6.3.4.a).

6.3.3 CAUDALES DE DISEÑO

El caudal de diseño de las tuberías de distribución se calculará de acuerdo con el método de Hunter. Este método, basado en el cálculo de probabilidades de uso simultáneo y en observaciones empíricas, otorga pesos para cada tipo de aparato sanitario de funcionamiento intermitente. Dichos pesos consideran, para tal accesorio, el caudal requerido, su duración y su frecuencia usual de operación. Esto se cuantifica con las denominadas unidades de accesorio de abastecimiento de agua (u.a). Tales unidades se han seleccionado de manera que el caudal total de un sistema o subsistema con diferentes clases de accesorios y sus condiciones de servicio, pueda ser aproximado como múltiplo de ese factor.

La tabla 6.1 indica las unidades de accesorio para diferentes accesorios sanitarios, bajo diferentes condiciones de servicio. En el caso de que el accesorio no esté contemplado en dicha tabla, se podrá utilizar la tabla 6.3.

El caudal máximo probable en un ramal de alimentación es función de la suma de las unidades de accesorio de todos los aparatos servidos suplidos por dicho ramal. La relación entre el total de las unidades de accesorio y el caudal máximo probable está descrita formalmente por las ecuaciones de la tabla 6.4, pero pueden encontrarse según la tabla 6.5 o con el gráfico de la figura 6.4.

Cuando un sistema no abastece ningún inodoro, el caudal correspondiente se obtiene utilizando las ecuaciones o valores correspondientes a un sistema donde predominen los inodoros con tanques de lavado.

Para la estimación del caudal en cualquier tubería de abastecimiento de agua en una edificación, se debe sumar al caudal de los accesorios toda carga de cualesquiera otros sistemas, tales como los aspersores del sistema contra incendios (caso residencial), requerimientos del sistema de aire acondicionado, generadores de agua caliente o vapor, sistemas de irrigación, entre otros.

6.3.4 PÉRDIDAS DE CARGA

Para el cálculo de las pérdidas de carga originadas por fricción en las tuberías de distribución y los ramales de alimentación, se recomienda la utilización de la fórmula de Darcy-Weisbach, dado que presenta la mayor precisión para calcular las pérdidas de carga en tuberías. Sin embargo, el profesional responsable de diseño podrá utilizar otras formulaciones aceptadas por las buenas prácticas de la profesión. El método de Darcy- Wisbach se expresa de la siguiente manera:

Donde, D= diámetro interno de la tubería (m) f= factor de fricción g= aceleración de la gravedad (m/s}) hf= pérdidas de energía (m) L= longitud de la tubería (m) V= velocidad del líquido en la tubería (m/s) Para sistemas de agua a presión se puede utilizar el siguiente arreglo de la ecuación de Darcy:

Donde, Q= caudal en la tubería (L/s) D= diámetro interno de la tubería (mm) El coeficiente de fricción f se calcula a partir de la fórmula de Colebrook White, o su equivalente gráfico, el diagrama de Moody. La ecuación de Haaland, que se muestra a continuación, es explícita y aproxima la ecuación de Colebrook White, con un error menor del 2% en el cálculo del factor de fricción.

TABLA 6.6 RUGOSIDADES ABSOLUTAS PARA LA FÓRMULA DE COLEBROOK WHITE

Se deberán considerar las pérdidas localizadas o pérdidas menores provocadas por cambios de dirección, válvulas, reducciones, medidores de caudal y otros accesorios. La tabla 6.7 y la figura 6.5 contienen los coeficientes de pérdidas locales necesarios para estimar las pérdidas en metros de columna de agua.

6.4 REQUISITOS CONSTRUCTIVOS EN INSTALACIONES DE AGUA POTABLE 6.4.1 INSTALACIÓN Y UBICACIÓN

En edificios de tres o más plantas, las tuberías de agua fría y agua caliente en tramos verticales se colocarán en ductos previstos para tal fin, cuyo tamaño deberá ser suficiente para su instalación, revisión, reparación y remoción convenientes.

Entre las tuberías de agua fría y agua caliente instaladas en un mismo ducto deberá existir una separación mínima de diez centímetros (0,10 m) de borde a borde, a no ser que se protejan con un material aislante adecuado.

Se permitirá la colocación en un mismo ducto vertical, de los bajantes de aguas residuales, de aguas pluviales y la tubería de abastecimiento o distribución de agua fría o caliente, siempre y cuando exista una separación mínima de veinte centímetros (0,20 m) de borde a borde entre ellas.

Es recomendable que las tuberías horizontales de alimentación de agua (tanto fría como caliente) se instalen con pendiente hacia la tubería vertical de alimentación correspondiente. Siempre que sea posible, se colocarán válvulas de purga en los puntos bajos de las tuberías horizontales de la planta baja. Si el edificio dispone de sótano, se deberán colocar válvulas de purga en los puntos más bajos de las tuberías horizontales.

Golpe de ariete. Para atenuar las sobrepresiones que pueda causar el golpe de ariete, se recomienda la instalación de cámaras de aire o de accesorios especiales para tal fin.

Las cámaras de aire consisten en extensiones verticales con finales ciegos de la tubería de alimentación de lavatorios, fregaderos, duchas y bañeras. Estas extensiones serán de diámetro igual o mayor al de la tubería de alimentación y su longitud será de sesenta centímetros (0,60 m). Las cámaras de aire llegan a dejar de funcionar con el tiempo, por lo que no se recomienda su utilización en edificios comerciales, industriales, hospitalarios o de reunión pública.

6.4.2 SOPORTE DE TUBERÍAS Y ELEMENTOS ESTRUCTURALES

Para el paso de las tuberías a través de los elementos estructurales se colocarán camisas o manguitos. La longitud del manguito o camisa será igual al espesor del elemento y su diámetro será tal que permita el paso adecuado de las tuberías y el aislamiento, de forma que se tenga un claro entre el manguito y la tubería (o el aislamiento) de al menos doce milímetros (12 mm).

Las tuberías colgantes horizontales y verticales estarán sujetas por abrazaderas que se fijarán al techo o muro mediante dispositivos de suspensión de material resistente. El espaciamiento entre los soportes se determinará de acuerdo con la resistencia mecánica de las tuberías, pero no será mayor que los valores dados en la tabla 6.9. En la selección del material de la abrazadera se deberá considerar la prevención de la corrosión galvánica.

Las tuberías que atraviesen juntas de dilatación o expansión en edificios deberán estar provistas, en sitios de paso, de conexiones flexibles o uniones de expansión. De igual forma, aquellas que puedan estar sujetas a vibraciones se protegerán mediante juntas flexibles en la conexión con equipos mecánicos.

Las dimensiones de las abrazaderas y dispositivos de suspensión deberán garantizar los requerimientos estructurales en materia de sustentación, estabilidad, esfuerzos causados en la tubería, pudiendo seleccionarse de acuerdo con la tabla 6.8.

Nota:

1. Se debe permitir la expansión del tubo cada 9,1 m.

6.4.3 TUBERÍAS ENTERRADAS

Cuando las tuberías de distribución de agua potable vayan enterradas, deberán alejarse lo más posible de los desagües de aguas residuales, debiendo estar separadas de estos a una distancia mínima de un metro (1,0 m) en planta y veinticinco centímetros (0,25 m) por encima. Cuando las tuberías de agua crucen los desagües, deberán colocarse siempre por encima de estos y a una distancia vertical no menor a veinticinco centímetros (0,25 m).

Las tuberías enterradas deberán colocarse en zanjas excavadas de dimensiones tales que permitan su fácil instalación. La profundidad mínima de la zanja será tal que haya al menos treinta centímetros (0,30 m) entre la corona del tubo y el nivel del terreno. Antes de proceder a la colocación de las tuberías, deberá compactarse el fondo de la zanja. Una vez colocadas las tuberías, rellenada y compactada la zanja, serán inspeccionadas y sometidas a las pruebas estipuladas en la sección 6.8. El relleno de la zanja se efectuará utilizando un material adecuado, extendido por capas horizontales de quince centímetros (0,15 m) de espesor como máximo, debidamente compactado.

Si se utilizan tuberías metálicas enterradas, estas deberán estar protegidas contra la corrosión con materiales adecuados. No se debe enterrar tubería de hierro galvanizado.

Las válvulas de las tuberías que queden bajo el nivel del terreno o del piso deberán estar provistas de una caja protectora. Esta caja deberá colocarse en un sitio accesible y será tal que permita la reparación, remoción y operación de las válvulas.

Las tuberías enterradas deberán estar alejadas de la cimentación de las edificaciones, con el fin de evitar someterla a altos esfuerzos de compresión. Las tuberías enterradas deberán ubicarse por encima de una proyección de 45° desde la placa de cimentación.

6.5 TANQUES DE ALMACENAMIENTO

Toda edificación ubicada en sectores donde el abastecimiento de agua no sea continuo o carezca de presión suficiente, deberá estar provisto de uno o varios tanques de almacenamiento que permitan el suministro de agua en forma adecuada a todas las piezas sanitarias o instalaciones previstas. Estos tanques podrán instalarse en los niveles inferiores (tanque de captación), en pisos intermedios, o sobre el edificio (elevados), siempre que cumplan con lo estipulado en este capítulo y estén de acuerdo con las características fundamentales de los modelos que se muestran en las +guras 6.6, 6.7 y 6.8.

Los tanques de agua deberán diseñarse de forma que garanticen la potabilidad del agua en todo momento e impidan la entrada de agua de lluvia, roedores u otros contaminantes.

En el caso de condominios y edificaciones multifamiliares, deberán contar con acceso directo desde las áreas comunes de la edificación para su debida operación, inspección y mantenimiento.

Los materiales para los tanques de almacenamiento deberán cumplir con los siguientes requisitos generales: impermeables, inodoros y que no den sabor al agua. Estos materiales pueden ser: plásticos, metales, fibrocemento, fibra de vidrio, concreto armado u otros materiales aprobados por la autoridad sanitaria.

El agua proveniente del lavado, desagüe o rebose de los tanques deberá dirigirse al sistema de drenaje de aguas residuales del edificio por medio de un desagüe indirecto.

La estructura de soporte de los tanques elevados deberá cumplir con lo estipulado en el artículo 3.16.

6.5.1 DIMENSIONAMIENTO Y DISPOSITIVOS

Cuando solo exista tanque elevado, es recomendable que su capacidad sea cuando menos igual al consumo diario total de las instalaciones. En casos en los cuales las interrupciones en el abastecimiento sean esporádicas, se podrá disminuir la capacidad de dicho tanque.

Cuando fuera necesario emplear una combinación de tanque de captación, bomba de elevación y tanque elevado, en el caso de los lugares donde se presenten problemas, como presión insuficiente del acueducto público o interrupciones continuas en el abastecimiento, la capacidad de los tanques dependerá de la jornada de bombeo, de la capacidad de las bombas y del patrón de consumo de la edificación. Si no se dispone de estos datos, es recomendable que la capacidad del tanque de captación sea al menos del 75% del consumo total diario y la del tanque elevado no menor a la mitad de dicho consumo.

Los tanques de almacenamiento estarán dotados de los dispositivos necesarios para su correcta operación, mantenimiento y limpieza, tales como registro, tubería de entrada con válvula de boya u otro mecanismo automático de control, tubería de salida con válvula de compuerta o de paso, tubería de ventilación, tubería de rebalse protegida contra la entrada de insectos y una tubería de limpieza que descargue sin provocar inundaciones (ver +guras 6.6, 6.7 y 6.8).

Las conexiones de las tuberías al tanque deberán hacerse de tal forma que no produzcan rotura en sus paredes y mantengan al tanque en sus condiciones iniciales. Las conexiones en tanques metálicos deberán evitar la corrosión electrolítica.

Todos los accesorios que necesiten cambio o reparación deberán instalarse en sitios accesibles. Las válvulas de los tanques que queden bajo el nivel del terreno o piso deberán estar provistas de una caja, de acuerdo con lo establecido en la sección 6.4.3.

El control de los niveles de agua en los tanques se hará por medio de dispositivos automáticos de control de nivel cuya función será:

a. Detener el flujo de entrada al tanque, cuando el nivel de líquido en el tanque elevado ascienda hasta el nivel máximo previsto.

b. Arrancar la bomba, cuando el nivel de agua en el tanque elevado descienda hasta la mitad de su altura.

c. Detener la bomba, cuando el nivel de agua en el tanque elevado ascienda hasta el nivel máximo previsto.

d. Detener la bomba, cuando el nivel del agua en el tanque de captación descienda hasta 15 cm por encima de la canastilla de succión.

Los tanques subterráneos y semienterrados deberán ser construidos con materiales apropiados y duraderos, resistentes a las solicitaciones de cargas que serán sometidos.

Todo tanque deberá tener un registro que permita su inspección, limpieza y eventual reparación. Se levantará un mínimo de quince centímetros (0,15 m) sobre el nivel del piso o terreno y estará ubicado de manera que no pueda sufrir contaminación o provocar inundación. En el caso de ser construidos con concreto, el mismo deberá ser armado o de bloques de concreto debidamente reforzados, rellenos de concreto y revestidos de mortero de cemento.

La capacidad adicional de los tanques de almacenamiento para los fines de control de incendios, deberá estar de acuerdo con lo indicado en el Reglamento General sobre Seguridad Humana y Protección contra Incendios.

6.5.2 LOCALIZACIÓN Y DIMENSIONAMIENTO DE TUBERÍA

La distancia vertical entre el techo de un tanque y el eje del tubo de entrada del agua no podrá ser menor a quince centímetros (0,15 m). En aquellos tanques donde la tapa cubra toda su superficie y exista acceso directo a los dispositivos de entrada, esta distancia podrá disminuirse a diez centímetros (0,10 m).

El tubo de rebalse debe ser de un diámetro mayor al del tubo de entrada y de al menos veinticinco milímetros (0,025 m) de diámetro. Este tubo deberá descargar en un sitio visible donde se adviertan claramente posibles vertidos.

La posición del tubo de rebalse será tal que su corona quede al mismo nivel con el fondo del tubo de entrada. La distancia entre el fondo del tubo de rebalse y el nivel máximo del agua será igual al diámetro del tubo de rebalse y no menor a veinticinco milímetros (0,025 m).

La tubería de desagüe o de limpieza se ubicará de manera que permita el vaciado completo del tanque. Tendrá un diámetro no menor a veinticinco milímetros (0,025 m) y deberá estar provista de una válvula.

La tubería de aducción desde el abastecimiento público hasta el tanque elevado deberá calcularse para suministrar el consumo total diario en un tiempo no mayor a cuatro horas.

Esta tubería deberá estar provista de su correspondiente llave de paso. Cuando se trate de edificios de una o dos plantas, el diámetro de la tubería de aducción al tanque elevado podrá seleccionarse de acuerdo con la dotación diaria y a la capacidad del tanque, según la tabla 6.10.

Nota:

1. Diámetro interior de la tubería.

Estos diámetros han sido calculados suponiendo un tiempo de cuatro horas para el llenado del tanque elevado.

Los tanques de captación deberán alejarse lo más posible de muros medianeros y alcantarillados de aguas residuales o pluviales, cuya distancia entre bordes debe ser de al menos dos metros (2,00 m).

Ningún tanque de captación podrá instalarse en un lugar sujeto a inundación o filtración de aguas de lluvia o residuales.

6.6 EQUIPOS DE BOMBEO 6.6.1 NORMAS GENERALES

La selección de los equipos de bombeo deberá hacerse con base en las curvas características de los mismos, su región de operación de preferencia y su región aceptable de funcionamiento, así como con las condiciones de funcionamiento del sistema de distribución, determinando en forma correcta los puntos de operación que corresponden con los diferentes regímenes de funcionamiento considerados. La potencia del motor deberá estar de acuerdo con los requerimientos de potencia hidráulica del sistema.

Para el bombeo de agua en los edificios se recomienda, en general, la utilización de bombas centrífugas.

Las bombas instaladas en las edificaciones, destinadas al abastecimiento de agua, no podrán conectarse directamente a la red pública, únicamente será a través de un tanque de captación, según lo dispuesto en el artículo 6.1.8, incisos b y c.

6.6.2 DIMENSIONAMIENTO

Cuando el sistema de distribución de agua esté provisto de tanque de captación y tanque elevado, la capacidad del equipo de bombeo deberá ser tal que permita llenar el tanque elevado en el tiempo establecido en la sección 6.5.2-5.

Los diámetros de las tuberías de impulsión de las bombas se determinarán en función del caudal de bombeo y de la carga dinámica total. Los diámetros de las tuberías de succión de las bombas se determinarán de acuerdo con la carga neta de succión requerida de la bomba.

La potencia de la bomba podrá calcularse mediante la siguiente ecuación:

Los motores eléctricos que accionen bombas deberán tener una potencia nominal del 130% de la absorbida por la bomba, si son trifásicos, y del 150% si son monofásicos. En caso de que se disponga de datos técnicos precisos, podrá calcularse la potencia requerida, tomando en cuenta tales características. Estos datos deberán entenderse como una guía y no como una exigencia.

6.6.3 INSTALACIÓN

Los equipos de bombeo de los sistemas de distribución de agua instalados dentro de los edificios deberán ubicarse en ambientes adecuados y que satisfagan requisitos tales como espacio libre alrededor de la bomba suficiente para su fácil reparación o remoción, piso con pendiente hacia desagües previstos, minimización de la contaminación acústica o sónica, seguridad y ventilación adecuada para el local. Los equipos que se instalen en el exterior deberán estar protegidos adecuadamente contra la intemperie y disponerse de tal forma que la contaminación acústica o sónica se minimice.

Los equipos de bombeo deberán instalarse sobre una fundación de concreto, dimensionada para absorber las vibraciones. Los equipos se fijarán sobre la fundación mediante pernos de anclaje, de acuerdo con las recomendaciones del fabricante del equipo de bombeo.

Las conexiones de la bomba a las tuberías de succión e impulsión deberán cumplir con los siguientes requisitos:

a. Las juntas entre la bomba y las correspondientes tuberías preferible mente serán del tipo de brida o de tope.

b. Las juntas inmediatamente adyacentes a las tuberías de impulsión para diámetros de treinta y dos milímetros (0,032 m) y mayores serán del tipo flexible.

c. Las tuberías de succión y aducción deberán descansar sobre soportes independientes de las fundaciones de la bomba. Su instalación será con el menor número posible de codos o figuras.

d. En el caso de bombas de recirculación de agua caliente, deberán usarse juntas de dilatación, tanto en la tubería de succión como la de aducción.

e. Los diámetros de las tuberías de succión serán siempre mayores o iguales que los de las tuberías de impulsión.

f. Para efectos de prueba de la bomba, se recomienda que la descarga tenga una prevista en forma de unión en T con su respectiva válvula de compuerta.

g. Se recomienda instalar en la tubería de impulsión, a corta distancia de la bomba, un manómetro cuya capacidad este acorde con la presión desarrollada por la bomba. De igual manera, se recomienda instalar un manómetro en la tubería de succión, a corta distancia de la bomba, cuyo rango de medición esté en concordancia con la carga de succión que pueda experimentar la tubería.

h. En caso de requerirse reducción de diámetro en la succión de la bomba, deberá de utilizarse una reducción excéntrica, que evite la acumulación del aire.

En las tuberías de descarga se utilizarán reducciones concéntricas cuando sea necesario.

En la tubería de impulsión, inmediatamente después de la bomba deberá instalarse una válvula de retención y una válvula de compuerta.

En las tuberías de succión con carga positiva se instalará una válvula de compuerta. En el caso de que trabaje con carga de succión negativa, para prevenir el descebado de la bomba, deberá instalarse una válvula de retención (o de pie) con su respectivo filtro en su extremo inferior.

En sistemas de bombeo de alta capacidad o para cargas elevadas, deberá estudiarse la conveniencia de instalar válvulas desaireadoras, válvulas de alivio de presión o algún otro sistema para contrarrestar los efectos del golpe de ariete.

Las bombas y motores eléctricos instalados en los sistemas de distribución de agua de los edificios deberán estar identificados con placas en las cuales figuren grabados, en forma indeleble, los datos y características de los mismos, tales como:

a. Para la bomba: marca, modelo, tipo, número de serie, caudal, presión, velocidad y potencia hidráulica b. Para el motor: marca, modelo, serie, voltaje y corriente por fase, factor de potencia, factor de servicio, velocidad, frecuencia, tipo de aislamiento, clase y temperatura ambiental aceptable

Los motores deberán tener su alimentación independiente derivada directamente del tablero de control. El equipo deberá estar dotado de una adecuada protección contra sobrecargas, cortocircuitos, pérdida de fase, inversión de fase y sobrecalentamiento.

Los equipos de bombeo para trabajo combinado con los tanques de captación, sistemas hidroneumáticos y de extinción de incendios, deberán estar dotados de un sistema de control automático que garantice su operación adecuada.

En equipos de bombeo que se utilicen en edificios o instalaciones que así lo requieran, deberá preverse su conexión a un sistema alterno de energía para casos de emergencia.

Todos los equipos de bombeo e instalaciones de abastecimiento de agua en edificios cubiertos por este reglamento deberán tener un plan de mantenimiento que asegure una condición adecuada de operación.

6.7 EQUIPOS HIDRONEUMÁTICOS

En lugares donde el abastecimiento público de agua no garantice presión suficiente para los requerimientos de la edificación, podrán instalarse equipos hidroneumáticos para mantener una presión adecuada en el sistema de distribución de agua. Los tanques hidroneumáticos no deben ser utilizados para la protección contra incendios.

Para la instalación de equipos hidroneumáticos, deberá disponerse de un tanque bajo con capacidad mínima para el consumo total diario del edificio.

6.7.1 BOMBAS

Las bombas deben seleccionarse para satisfacer las presiones requeridas por el sistema, según lo establecido en la sección 6.3.1, incluyendo el rango de operación del tanque hidroneumático.

Para la condición de demanda máxima, se recomienda que los arranques por hora del motor del sistema de bombeo no excedan las recomendaciones del fabricante. Como guía, se sugieren los siguientes valores:

. Motores mayores de 4 kW: 6 a 8 ciclos/hora.

. Motores entre 4 y 2 kW: 8 a 15 ciclos/hora.

. Motores menores de 2 kW: 15 a 25 ciclos/hora.

El caudal de operación de la bomba será igual al consumo máximo de la instalación servida por el sistema hidroneumático durante la duración del ciclo de operación. El consumo máximo horario de la instalación puede determinarse de dos maneras:

a. A partir del caudal promedio diario establecido según las dotaciones indicadas en el capítulo 4, multiplicado por un factor de maximización de veinte (20) en el caso de viviendas y diez (10) en el caso de oficinas y comercios.

b. A partir del caudal máximo instantáneo probable de la instalación, que se establece en la sección 6.3.3, según la siguiente expresión:

6.7.2 TANQUES HIDRONEUMÁTICOS

Las bombas y los motores del sistema hidroneumático deberán cumplir, además, con los requisitos exigidos en la sección 6.6, en cuanto les sean aplicables.

El ámbito de presiones de operación del tanque hidroneumático debe garantizar que las presiones máximas y mínimas en el sistema cumplan con lo establecido en la sección 6.3.1.

El volumen total del tanque hidroneumático se puede determinar según las siguientes expresiones:

El volumen calculado según las fórmulas anteriores incluye un 10% adicional para asegurar el sello de los tubos de entrada y salida del líquido. Además, en el caso de instalaciones con compresor, incluye un 10% adicional como margen de seguridad contra posibles pérdidas de aire en el sistema.

El nivel mínimo de agua en el tanque hidroneumático deberá ser tal que cubra las conexiones de entrada y salida del agua, así como que evite que el aire escape por dichas conexiones. Se recomienda que el volumen de agua ocupado por el sello no sea inferior al 10% del volumen total del tanque.

Los tanques hidroneumáticos deberán tener un sistema de carga de aire del tipo automático; los tanques con una capacidad igual o mayor a los tres mil litros (3000 L) deberán disponer de un compresor de aire para tales efectos.

La capacidad de los compresores para sistemas hidroneumáticos debe ser tal que comprima un volumen de aire igual a la capacidad del tanque, desde la presión atmosférica hasta la presión mínima de trabajo del tanque (Pmin) en un plazo de al menos una hora y media.

El sistema hidroneumático deberá dotarse de los implementos que se indican a continuación:

a. Dispositivo de control automático y manual b. Interruptor de presión para arranque a presión mínima y parada a presión máxima c. Manómetro en el tanque de agua d. Válvula de seguridad e. Válvulas de compuerta con uniones de tope que permitan la operación y desmontaje de equipos y accesorios f. Válvulas de retención en las tuberías de descarga de la bomba al tanque hidroneumático g. Llave de compuerta colocada de tal forma que con ella se pueda drenar todo el contenido del tanque h. Dispositivo automático para detener el funcionamiento de las bombas y compresor (si lo hubiera) en caso de falta de agua i. Uniones flexibles para absorber las vibraciones j. Se debe proveer un sistema de desvío (by pass) que permita el abastecimiento de la edificación directamente de la red, en caso de avería o de mantenimiento del sistema hidroneumático.

La figura 6.9 muestra un modelo de un sistema hidroneumático.

Los tanques hidroneumáticos se apoyarán sobre soportes adecuados y, además, a los horizontales se les colocará sobre los soportes láminas de material aislante, para absorber las expansiones a que estarán sometidos. Estos tanques horizontales se instalarán con pendiente mínima de un 1% hacia el drenaje o limpieza previsto.

6.8 INSPECCIÓN Y PRUEBA DE LAS INSTALACIONES DE ABASTECIMIENTO DE AGUA POTABLE

Las instalaciones de abastecimiento de agua deberán inspeccionarse y probarse antes de que entren en servicio.

Para verificar el cumplimiento del proyecto aprobado, el profesional responsable de la obra deberá inspeccionarla regularmente, según las estipulaciones establecidas en la normativa del CFIA, exigiendo, en casos de alteración, las correcciones a que hubiere lugar, como requisito indispensable para aprobar la obra.

El profesional responsable de la obra está en la obligación de probar el sistema, como garantía de su buena ejecución y diseño, según la prueba de ensayo hidrostático que se describe a continuación:

a. La prueba debe realizarse antes de instalar las piezas sanitarias, colocándose tapones en los lugares correspondientes. Las tuberías por probar deberán estar libres de materiales ajenos y de residuos.

b. Inyectar agua con la ayuda de una bomba hasta lograr una presión de 700 kPa.

c. Observar que dicha presión se mantenga constante en el manómetro durante un lapso mínimo de quince (15) minutos, admitiéndose una disminución no mayor de 15 kPa sin acción de la bomba.

d. Si el manómetro indica descenso de la presión, buscar los puntos de posibles fugas, los cuales deben ser adecuadamente corregidos hasta que se cumpla lo suscrito en el inciso c de este artículo.

e. Para los efectos de seguridad de la prueba, deberán usarse manómetros con sensibilidad suficiente para indicar cambios de presión pequeños, del orden de 5 kPa o inferiores.

En casos determinados o especiales, la autoridad sanitaria podrá someter las instalaciones a las pruebas adicionales que considere pertinentes.

6.9 DESINFECCIÓN SANITARIA

Después de que la red interior de agua potable o cualquier parte de ella haya sido instalada o reparada, deberá ser lavada y desinfectada. El procedimiento de desinfección, mientras la autoridad sanitaria no indique otro procedimiento, será el siguiente:

a. El sistema de tuberías deberá ser llenado con agua potable, hasta que reboce en los accesorios. Las tuberías por desinfectar deberán estar libres de materiales ajenos y de residuos.

b. El sistema se llenará usando una solución de al menos 50 mg/L de cloro, la que deberá actuar en el interior de la tubería durante al menos tres (3) horas.

Durante el proceso de la cloración, todas las válvulas y otros accesorios serán operados repetidas veces, para asegurar que todas sus partes entren en contacto con la solución de cloro.

c. Después de la desinfección, el agua con cloro será totalmente expulsada de la tubería llenándola con el agua dedicada al consumo.

d. El proceso se deberá repetir, si mediante exámenes bacteriológicos se comprueba la persistencia de elementos contaminantes o una alta concentración de cloro.

Antes de llevar a cabo la desinfección de los tanques de almacenamiento, se deberán llenar con agua para detectar filtraciones. En el caso de estructuras de concreto, se recomienda realizar una impermeabilización del tanque. Una vez detectadas las filtraciones, en caso de haberlas, se drenará el tanque y se llevará a cabo su reparación. La desinfección se hará de la siguiente manera:

a. Las paredes del tanque se lavarán con una escoba o cepillo de acero, usando una solución concentrada de hipoclorito de calcio o de sodio (150 a 200 mg/L).

b. El tanque se llenará con una solución que presente como mínimo 50 mg/L de cloro y deberá permanecer en el tanque durante 12 horas, como mínimo. Durante este tiempo, las válvulas se deberán accionar repetidamente, de modo que estas y los accesorios también entren en contacto con el desinfectante.

c. Después de la desinfección, el agua con cloro se drenará completamente del tanque.

d. Cuando no se disponga de hipoclorito de calcio o de sodio para realizar la desinfección, se podría utilizar, con previa autorización de su uso por parte de la autoridad sanitaria competente, otros compuestos biocidas para el proceso de desinfección. Estos compuestos deberán poseer una certificación de que no son dañinos para la salud humana, otorgada por alguna organización mundial, por ejemplo la Organización para la Salud y Seguridad Pública (NSF International, por su siglas en inglés).

6.10 INSTALACIONES DE AGUA CALIENTE 6.10.1 NORMAS GENERALES

Para la producción, almacenamiento y distribución de agua caliente se deberán cumplir las disposiciones de la presente sección, además de lo establecido en los artículos anteriores para sistemas de agua potable.

Las instalaciones de agua caliente en los edificios deben satisfacer los requerimientos de consumo y no deberán presentar riesgos de accidentes.

Los equipos para la generación de agua caliente serán construidos de manera que sean resistentes a las presiones y temperaturas máximas que puedan darse en el sistema, así como ser resistentes a la corrosión y estar provistos de todos los dispositivos de seguridad y de limpieza requeridos según la normativa vigente y la buena práctica constructiva.

Todo equipo de generación de agua caliente estará provisto de dispositivos automáticos para el control de temperatura y para el corte de la fuente de energía. Dichos dispositivos deberán instalarse en forma tal que suspendan el suministro de energía antes de que el agua en el tanque alcance una temperatura de 60 °C para viviendas; 70 °C para restaurantes, hoteles y similares; 80 °C para hospitales, clínicas y afines. El sensor de temperatura deberá ubicarse en la zona de máxima temperatura del agua.

Los sistemas de generación de agua caliente dispondrán de válvulas de seguridad para controlar el exceso de presión. Dichos dispositivos se graduarán de modo que inicien su operación a una presión un 10% mayor que la del funcionamiento normal del sistema.

Su ubicación será en el equipo de generación o en su tubería de salida a una distancia máxima de treinta centímetros (0,30 m) del equipo, siempre que no existan válvulas entre la válvula de seguridad y dicho equipo.

Los sistemas de generación de agua caliente que operan con gas combustible y sean del tipo abierto no deberán instalarse en cuartos de baño, dormitorios, cuartos de duchas o de limpieza. En este tipo de recintos solo se podrán usar aquellos de tipo estanco.

6.10.2 INSTALACIÓN

El sitio donde se realice la instalación de un calentador de agua deberá ser accesible para su inspección, mantenimiento o reemplazo.

Los calentadores de agua deberán ubicarse en piezas no habitables de la casa, a excepción de los calentadores de agua instantáneos, siempre y cuando sean eléctricos o ventilados directamente.

Cuando el sistema de alimentación de agua caliente del edificio es del tipo simple o sin recirculación, deberá instalarse una válvula de retención en la tubería de alimentación de agua caliente.

Deberá instalarse una válvula de control en la tubería de abastecimiento de agua fría al sistema de generación de agua caliente. Además, para separar el tanque de agua caliente de las tuberías y facilitar su mantenimiento, las conexiones de entrada y salida serán de uniones de tope.

Los escapes de vapor o agua caliente provenientes de los dispositivos de seguridad y control deberán evacuarse en forma indirecta al drenaje. Las descargas estarán ubicadas de manera que no causen accidentes, molestias, ni daños a estructuras, equipos y propiedades, pero que permita su observación por los ocupantes del edificio. El diámetro de la tubería de descarga deberá ser como mínimo el diámetro de salida de la válvula de alivio. La tubería de descarga deberá permitir el drenaje por gravedad y su parte final deberá estar a una distancia no mayor a quince centímetros (0,15 m) sobre el nivel del piso.

Materiales. En los sistemas de agua caliente, las tuberías de distribución podrán ser de hierro galvanizado, cobre o CPVC. Se podrán utilizar tuberías de otros materiales,; sin embargo, se debe tener presente la revisión por parte de la autoridad sanitaria competente y otras instituciones del Estado.

En las tuberías del sistema de agua caliente se deberán instalar las juntas de dilatación suficientes para evitar pandeo, desplazamiento excesivo o rotura de las tuberías.

Los calentadores de agua deberán encontrarse a una distancia no menor a treinta centímetros (0,30 m) de cualquier muro lateral o trasero. Esto en el caso de que el fabricante del equipo no realice indicación al respecto.

Los calentadores a base de gas que se instalen en edificaciones residenciales deberán ser instalados de tal forma que los quemadores o dispositivos de ignición se encuentren a una distancia mínima de cincuenta centímetros (0,5 m) del piso.

e deberán instalar válvulas para controlar el exceso de presión, además de instalarse una válvula de retención en la tubería de abastecimiento de agua fría.

La instalación de calentadores de agua a gas deberá cumplir además con lo estipulado en la norma NFPA 54 Código Nacional de Gas Combustible o NFPA 58 Código del Gas Licuado de Petróleo.

La instalación de calentadores de agua eléctricos deberá cumplir con lo estipulado en el Código Eléctrico de Costa Rica para la Seguridad de la Vida y de la Propiedad o, en su defecto, a la norma NFPA 70 Código Eléctrico Nacional.

6.10.3 AIRE DE COMBUSTIÓN

Los calentadores de agua que utilicen combustibles deberán instalarse en sitios con buena ventilación, que permitan una adecuada combustión del equipo y ventilación de los gases de escape.

En edificios que presenten una alta hermeticidad respecto a la infiltración de aire, el aire de combustión deberá obtenerse desde fuera. Para edificios con una hermeticidad ordinaria, todo o una porción del aire requerido para la combustión podrá ser obtenido por infiltración, si el volumen de aire encerrado es de al menos un metro cúbico (1 m3) por cada doscientos cinco watts (205 W) de capacidad del calentador.

El área neta libre de las aberturas o ductos para suplir el aire necesario de la combustión se presentan en la tabla 6.11.

Nota:

Se considera un sitio no con+nado a todo aquel cuarto o lugar que tenga un volumen de al menos 1 m3 por cada 205 W de capacidad del calentador de agua. Habitaciones que se comuniquen directamente con este espacio, a través de aberturas sin aditamentos, tales como puertas, se consideran como parte del sitio confinado.

Las aberturas para el ingreso de aire deberán localizarse de tal forma que:

. Una apertura debe localizarse a una distancia, por sobre la parte más alta del calentador de agua, no menor a 30 cm.

. Otra apertura debe localizarse por debajo del nivel de cielorraso del cuarto, a una distancia no menor de 30 cm.

. Las aberturas deben ser de mayor tamaño que el calentador, debiendo terminar a una distancia mínima de 7,5 cm por sobre los lados o frente del calentador.

. Las aberturas deben servir a un solo cuarto cerrado.

Los requerimientos indicados en la tabla 6.11 son solo una referencia. La forma en que se supla el aire de combustión podrá diseñarse de acuerdo con principios reconocidos y buenas prácticas de la Ingeniería, mientras no contravenga con las disposiciones de las autoridades relacionadas.

6.10.4 VENTILACIÓN Y GASES DE COMBUSTIÓN

Los calentadores de agua que requieran de chimeneas o ductos para expulsar los gases de ventilación deberán cumplir con lo dispuesto por el fabricante del equipo; además, para el diseño dimensionamiento se podrá utilizar las indicaciones de la norma NFPA 54, Código Nacional de Gas Combustible.

Los ductos de chimenea deberán ser adecuados para llevar los gases de combustión y deberán cumplir con las especificaciones del fabricante del calentador, así como también lo dispuesto por la NFPA 54 Código Nacional de Gas Combustible.

El sistema de ventilación deberá diseñarse para que este desarrolle un flujo positivo que transporte todos los productos de la combustión hacia las afueras del edificio.

La descarga de los ductos que atraviesan muros o salen hacia el techo deberá finalizar en un tipo de sombrerete adecuado, el cual debe ser instalado según las instrucciones del fabricante.

La descarga de los ductos que finalicen sobre el techo deberá sobrepasar en al menos sesenta centímetros (0,60 m) el punto más alto del techo ubicado en un radio de tres metros (3 m).

La descarga de los ductos deberá finalizar respetando las siguientes dimensiones:

a. Deberá encontrarse a una distancia no menor a ciento veinte centímetros (1,20 m) por debajo de cualquier puerta, ventana (que sirva para efectos de ventilación), o entradas de aire (por gravedad).

b. Deberá estar a una distancia no menor a ciento veinte centímetros (1,20 m) horizontalmente de cualquier puerta, ventana (que sirva para efectos de ventilación), o entradas de aire (por gravedad).

c. Deberá estar a una distancia no menor a treinta centímetros (0,30 m) por encima de cualquier puerta, ventana (que sirva para efectos de ventilación), o entradas de aire (por gravedad).

d. Deberá estar a una distancia no menor a noventa centímetros (0,90 m) por encima de cualquier entrada de aire forzada, localizada en un radio de tres metros (3 m).

e. Deberá estar a una distancia no menor a sesenta centímetros (0,60 m) por encima de cualquier muro o baranda, localizada en un radio de tres metros (3,0 m).

6.10.5 DISTRIBUCIÓN Y ALMACENAMIENTO DE AGUA CALIENTE

Se podrán utilizar calentadores de agua eléctricos, de gas o de energía solar, ya sean del tipo de alimentación directa o con tanque.

El abastecimiento de agua potable para los calentadores se podrá realizar por cualquiera de los siguientes medios:

a. Directamente de la red pública.

b. De un tanque de captación de agua fría.

c. De un tanque hidroneumático.

La distribución de agua caliente se podrá realizar mediante los siguientes métodos:

sistema con recirculación y sistema sin recirculación. El primero podrá ser del tipo forzado o por gravedad.

. Sistema con recirculación: este se recomienda en edificaciones de tres (3) o más plantas, o en aquellos casos donde las piezas sanitarias o los puntos donde se requiera agua caliente se encuentren distribuidos en áreas extensas, con especial atención a los casos en que sea necesario un abastecimiento de agua constante e instantáneo, tales como hospitales, clínicas y hoteles, entre otros.

. Sistema sin recirculación: se utiliza en instalaciones pequeñas, viviendas unifamiliares y edificaciones de hasta tres plantas.

Las dotaciones para agua caliente estarán de acuerdo con lo establecido para sistemas de agua fría en el capítulo 4, de la siguiente manera:

a. Uso doméstico. La dotación diaria mínima será una sexta parte de la dotación fijada para agua fría.

b. Hospedaje y alojamiento. La dotación diaria mínima será de una cuarta parte de la dotación fijada para agua fría.

c. Restaurantes y similares. La dotación diaria mínima será de dos litros por persona servida.

d. Residencias estudiantiles. La dotación diaria mínima será de una cuarta parte de la dotación fijada para agua fría.

e. Gimnasios. La dotación diaria mínima será de cinco litros por metro cuadrado (5,0 L/m2) de área efectiva.

f. Hospitales, clínicas y similares. La dotación diaria mínima para clínicas y hospitales será de dos quintas partes de la dotación fijada para agua fría. La dotación diaria para clínicas dentales será de un octavo de la dotación fijada para agua fría.

Para el cálculo de la capacidad del equipo de generación de agua caliente, cuando disponga de un tanque de captación, se utilizarán las relaciones que se indican en la tabla 6.12, de acuerdo con el consumo de agua caliente asignado.

7. SISTEMAS DE DESAGÜE DE AGUAS RESIDUALES 7.1 NORMAS GENERALES

Las instalaciones sanitarias de aguas residuales deberán diseñarse y construirse de forma que permitan la rápida evacuación de los desechos, eviten obstrucciones, impidan el paso de gases y olores del sistema al interior de las edificaciones, no permitan el escape de líquidos ni formación de depósitos en el interior de las tuberías y no contaminen el agua de consumo.

Las tuberías y accesorios de los sistemas de desagüe de aguas residuales serán de un material duradero, libre de defectos y cumplirán con los requisitos y especificaciones indicadas en los artículos de la sección 7.2 de este Código.

Cada mueble sanitario o accesorio conectado directamente con el sistema de desagüe de aguas residuales deberá equiparse con un sello de agua o sifón para evitar la entrada de malos olores al interior de la edificación.

Todo sistema de desagüe de aguas residuales deberá estar dotado de un número suficiente de cajas de inspección y registro para su limpieza y mantenimiento.

El sistema de desagüe de aguas residuales deberá contar con tuberías de ventilación que permitan una aireación adecuada, garantizando flujo a presión atmosférica.

Ningún mueble sanitario deberá instalarse en una habitación que no tenga ventilación ni iluminación adecuadas. Además, se respetarán las dimensiones indicadas en la sección 5.3 de este Código.

Las descargas de los sistemas de desagüe de aguas residuales deberán desecharse según lo indicado en el capítulo 3 de este Código.

En un sistema de desagüe de aguas residuales serán inadmisibles las siguientes condiciones:

a. Que las descargas de una edificación ingresen a las tuberías de otra edificación.

b. Que las tuberías de desagüe crucen el interior de tanques de almacenamiento de agua potable, ni que crucen sobre el techo o losa de cobertura de los mismos (ver sección 6.5.2).

c. Cajas de registro en habitaciones o lugares cerrados.

d. Conexiones cruzadas con otros sistemas.