GB 50242-2002 Code for Acceptance of Construction Quality of Building Water Supply, Drainage and Heating Engineering

General Provisions

• 第 1.0.1 条This code applies to the construction quality acceptance of building water supply, drainage and heating engin…
• 第 1.0.2 条This code is a mandatory standard, and the construction quality acceptance of water supply, drainage, and hea…
• 第 1.0.3 条The design, construction and acceptance of water supply, drainage and heating works in hotel buildings shall,…
• 第 1.0.4 条The requirements for construction quality acceptance set out in the engineering technical documents and contr…
• 第 1.0.5 条Construction quality acceptance shall be based on the design drawings, the construction contract and this cod…
• 第 3.1.3 条The main materials, equipment, finished products, and semi finished products used in the project shall have q…
• 第 3.1.4 条Concealed works shall be accepted by all parties prior to concealment, and concealed works acceptance records…
• 第 3.1.5 条Functional tests involving safety, hygiene, energy saving and environmental protection (such as pipeline pres…
• 第 3.1.6 条During construction, acceptance inspections of sub item works and divisional works shall be carried out and r…
• 第 3.2.1 条Before valve installation, strength and tightness tests shall be conducted; for each batch (same brand, same …
• 第 3.2.2 条Before pipe installation, internal dirt and debris must be removed; open ends shall be temporarily sealed whe…
• 第 3.2.3 条Metal or plastic sleeves shall be provided where pipes pass through walls and floor slabs, and shall comply w…
• 第 3.2.4 条Pipe joints shall not be located within sleeves, and the annular space between the pipe and the sleeve shall …
• 第 3.2.5 条The installation positions of pipe supports, hangers and brackets shall be correct; embedment shall be level …
• 第 3.2.7 条Before the domestic water supply system piping is put into service, it must be flushed and disinfected, and s…
• 第 3.2.8 条The indoor drainage system shall be provided with vent pipes in accordance with the design requirements, and …
• 第 3.2.10 条Floor drains shall be installed level, plumb and secure, set below the drainage surface, and provided with a …

Terminology

• 第 2.0.1 条Water supply system : A network that, through pipes and auxiliary equipment, delivers water in an organized m…
• 第 2.0.2 条Drainage system : A network that promptly discharges roof rainwater and the sewage and wastewater generated b…
• 第 2.0.3 条Hot water supply system : A network of pipes and auxiliary equipment designed to deliver hot water to meet sp…
• 第 2.0.4 条Sanitary fixtures : Equipment used to meet various hygiene requirements in people's daily lives and to collec…
• 第 2.0.5 条Water supply fittings : A collective term for various pipe fittings, valves and faucets used in water supply …
• 第 2.0.6 条Building reclaimed water system : A water supply system in which various types of drainage from civil buildin…
• 第 2.0.7 条Drain plug : A fitting installed at the drain outlet of fixtures such as sink, laboratory sink, service sink,…
• 第 2.0.8 条Floor drain : A special device used to drain surface water and prevent gases in the drainage pipe system from…
• 第 2.0.9 条Pipe expansion compensation : Compensation devices or measures installed in the piping system to prevent dama…

Basic Requirements

• 第 3.1.2 条Construction of building water supply, drainage and heating works must be carried out by construction units w…
• 第 3.2.11 条After the heating system installation is completed, a hydrostatic test shall be carried out, and flushing and…
• 第 3.2.12 条After radiators are assembled in groups, and before installation of radiators delivered as complete units, a …

Basic provisions

• 第 3.2.6 条After the piping system installation is completed, hydrostatic tests, water filling tests and water flow test…
• 第 3.2.9 条Sanitary fixtures shall be secured with embedded bolts or expansion bolts, and shall be firm, stable and free…

Indoor water supply

• 第 3.3.3 条Water supply pipes must use fittings compatible with the pipe material. Materials used in domestic water supp…
• 第 3.3.16 条Various pressure piping systems and equipment shall undergo hydrostatic testing, and non pressure piping syst…
• 第 4.2.1 条The hydrostatic pressure test of indoor water supply pipes must comply with the design requirements. When not…
• 第 4.2.2 条Before the water supply system is put into use, a water flow test must be conducted and properly documented.
• 第 4.2.3 条Before the domestic water supply system piping is put into service, it must be flushed and disinfected, and s…
• 第 4.2.5 条The horizontal clear distance between the water supply service pipe and the drainage discharge pipe shall not…
• 第 4.2.6 条The surface quality of welds on pipes and pipe fittings shall meet the following requirements: the weld profi…
• 第 4.2.7 条Water supply horizontal pipes shall have a slope of 2‰–5‰ toward the drain device.
• 第 4.2.8 条The allowable deviations for the installation of water supply pipes and valves shall comply with the provisio…
• 第 4.2.9 条The supports and hangers of pipes shall be installed level and securely, and their spacing shall comply with …
• 第 4.2.10 条Water meters should be installed in locations that are accessible for maintenance and protected from exposure…
• 第 4.3.1 条After the indoor hydrant system is installed, a hose discharge test shall be conducted using the test hydrant…
• 第 4.3.2 条Install the fire hydrant hose. After the hose is tied to the nozzle and quick coupling, hang or place the hos…
• 第 4.3.3 条The installation of box type fire hydrants shall comply with the following requirements: the hydrant valve ou…
• 第 4.4.1 条The allowable deviations for the installation of water supply equipment (such as water pumps, water tanks, et…
• 第 4.4.2 条The tank overflow pipe and drain pipe should be located near the drainage point but must not be directly conn…
• 第 4.4.3 条Spring isolators shall not be used for vibration isolation of vertical water pumps.
• 第 4.4.4 条Where pipes pass through walls and floor slabs, metal or plastic sleeves shall be provided. For sleeves insta…
• 第 4.5.1 条After the hot water supply system is installed and before the pipes are insulated, a hydrostatic test shall b…
• 第 4.5.2 条Hot water supply pipes should use natural bends to compensate for thermal expansion wherever possible; where …
• 第 4.5.3 条After completion of the hot water supply system, flushing must be carried out.
• 第 4.5.4 条Pipes in the hot water supply system shall be insulated (except exposed pipes in bathrooms). The insulation m…
• 第 4.5.5 条After the hot water supply system is installed and before the pipes are insulated, a hydrostatic test shall b…
• 第 4.5.6 条Pipes in the hot water supply system shall be insulated (except exposed pipes in bathrooms). The insulation m…
• 第 4.2.3 条2. Clause (flushing and disinfection) and 4.2.5 (water supply and drainage pipe spacing) are key points in ho…
• 第 4.3.1 条3. Clauses 4.3.3 (fire hydrants) and 4.4.4 (sleeves) are key control points for hotel fire safety and waterpr…
• 第 4.5.1 条4. Clause 4.5.6 (Hot Water System) is directly related to the hotel's hot water supply quality and energy sav…

Indoor drainage

• 第 10.2.1 条Buried or concealed drainage pipes must undergo a water filling test before concealment, and the water fillin…
• 第 10.2.4 条The slope of plastic sanitary sewage pipes must meet design or code requirements (e.g., minimum slope 0.012 f…
• 第 10.2.9 条The vent pipe must not be connected to an air duct or flue, and shall comply with the following requirements:…
• 第 10.2.10 条Install hospital bacteria laden sewage pipes that have not been disinfected; they must not be directly connec…
• 第 10.2.14 条Expansion joints must be installed in plastic drainage pipes in accordance with the design requirements and l…
• 第 10.2.15 条Drainage main risers and horizontal main pipes shall be subjected to a ball passing test; the test ball diame…
• 第 12.2.1 条Drain plugs and floor drains shall be installed level and secure, set below the drainage surface, with no lea…
• 第 12.2.3 条Before handover, sanitary fixtures shall undergo full water and flow tests. After filling with water, all con…
• 第 10.2.14 条Hotel buildings are typically high rise or super high rise, so (firestop collar installation) and 10.2.9 (ven…
• 第 12.2.1 条A floor drain water seal of ≥50 mm is key to preventing odors and is critical to guest room comfort in hotels.

Indoor hot water

• 第 6.2.1 条After the domestic hot water supply system is installed and before pipe insulation, a hydrostatic test shall …
• 第 6.2.2 条Inspection method for the hydrostatic pressure test of the hot water supply system: For steel pipe or composi…
• 第 6.2.3 条After the hot water supply system is completed, flushing must be carried out. Flushing shall use clean water …
• 第 6.2.4 条Pipes of the hot water supply system shall be insulated. The insulation material, thickness and protective ca…
• 第 6.2.5 条Hot water pipes shall be installed with a slope directed toward the drain device. Where not specified in the …
• 第 6.2.6 条Valves in the hot water supply system shall undergo strength and tightness tests before installation. For eac…
• 第 6.2.7 条Allowable deviations and inspection methods for hot water supply system installation (covering pipe horizonta…
• 第 6.2.8 条After the hot water supply system is installed, system commissioning shall be carried out. The commissioning …
• 第 8.2.2 条(Applicable to outdoor heating networks serving hotels) When conducting a hydrostatic test on heating pipes, …
• 第 第6.2.8条 条2. Hotel hot water systems typically involve circulating return water , so system commissioning (including ci…

Indoor domestic hot water

• 第 8.2.1 条(Applicable to outdoor heating networks serving hotels) The hydrostatic test pressure of heating pipes shall …

Sanitary fixtures

• 第 7.2.1 条Drain plugs and floor drains shall be installed level, secure, and below the drainage surface, with no leakag…
• 第 7.2.2 条Before handover, sanitary fixtures shall undergo full water and flow tests. (Ensure all hotel sanitary fixtur…
• 第 7.2.3 条Water supply fittings for sanitary fixtures shall be intact and undamaged, with tight connections and flexibl…
• 第 7.2.4 条The diameter and minimum slope of drainage pipes for sanitary fixtures must comply with design requirements. …
• 第 7.3.1 条Drainage pipe installation must comply with design requirements; no slope or reverse slope is strictly prohib…
• 第 7.3.2 条Drainage plastic pipes must be installed with expansion joints in accordance with the design requirements and…
• 第 7.3.3 条The main drainage stacks and horizontal main pipes shall all undergo a ball passing test; the ball diameter s…
• 第 8.2.1 条After radiator assembly, and before installation of factory assembled radiators, a hydrostatic test shall be …
• 第 8.2.2 条Radiator brackets and supports shall be installed at accurate positions and securely embedded. (Ensures stabl…
• 第 8.2.3 条The installation distance between the back of the radiator and the finished inner wall surface shall comply w…

Indoor heating

• 第 10.2.1 条Pipe installation slope: when steam and condensate flow in the same direction, the slope shall be 3‰ and shal…
• 第 10.2.4 条Compensator installation: Square compensators should be installed horizontally and consistent with the pipe s…
• 第 10.2.8 条When pipes pass through walls and floors, metal or plastic sleeves shall be provided. For sleeves installed i…
• 第 10.2.11 条Permissible deviations for heating pipe installation: the longitudinal and transverse bending of horizontal p…
• 第 10.3.4 条After radiator sections are assembled, and before the installation of factory assembled radiators, a hydrosta…
• 第 10.3.6 条The installation distance between the back of the radiator and the finished inner wall surface shall comply w…
• 第 10.4.3 条Low temperature hot water radiant floor heating system: the buried portion of the pipe coils laid beneath the…
• 第 10.4.4 条Low temperature hot water radiant floor heating system: A hydrostatic test must be performed before the coils…
• 第 10.4.6 条Low temperature hot water radiant floor heating system: The bent sections of heating coils shall not have har…
• 第 11.3.1 条System hydraulic pressure test: After the heating system installation is completed and before pipe insulation…
• 第 11.3.3 条System flushing: After the system passes the pressure test, the system shall be flushed and the strainers and…
• 第 11.3.5 条After system pressure testing and flushing, system trial operation and commissioning shall be carried out. Th…

Outdoor water supply

• 第 9.2.1 条Pipe burial depth : Water supply pipes must not pass directly through contamination sources such as sewage we…
• 第 9.2.4 条Valve installation : Outdoor water supply valves (such as the main valve on the service pipe and zone valves)…
• 第 9.2.5 条Pipe connection : When connecting metal pipes (such as ductile iron pipes and steel pipes) to plastic pipes (…
• 第 9.2.7 条Hydraulic pressure test : Outdoor water supply pipes must undergo a hydraulic pressure test. The test pressur…
• 第 9.2.8 条Flushing and disinfection : Before acceptance, the piping system must be flushed and disinfected, and may onl…
• 第 9.2.9 条Insulation and freeze protection : Water supply pipes located outdoors or in unheated areas (such as roof tan…
• 第 9.2.10 条Well chamber masonry : The dimensions of valve chambers, water meter chambers and other well chambers shall m…
• 第 9.1 条Note : Hotel buildings have high requirements for water supply continuity; the above clauses focus on ensurin…

Outdoor drainage

• 第 10.1.1 条This chapter applies to the quality acceptance of outdoor drainage network installation works for civil build…
• 第 10.2.1 条The slope of drainage pipes must comply with the design requirements; no slope or reverse slope is strictly p…
• 第 10.2.2 条Before pipe burial, water filling tests and flow tests must be carried out; drainage shall be unobstructed, f…
• 第 10.2.3 条When cement caulking is used for cast iron drainage pipes, the oakum shall be packed densely, and the joint c…
• 第 10.2.4 条Drainage plastic pipes must be installed with expansion joints in accordance with the design requirements and…
• 第 10.2.5 条The base (trench) treatment of drainage pipes must meet the design requirements; over excavation backfill or …
• 第 10.2.6 条The construction of drainage inspection manholes (including septic tanks and grease traps) must comply with t…
• 第 10.2.7 条When drainage pipes cross roads, railways, or other load bearing areas, sleeves must be added or other protec…
• 第 10.2.8 条Allowable deviation for outdoor drainage pipe installation: coordinate deviation ≤15 mm (buried), elevation d…

System commissioning

• 第 11.1.1 条Building water supply, drainage, and heating engineering must undergo system commissioning, and records shall…
• 第 11.2.1 条Before the indoor water supply system (including the domestic hot water system) is put into use, a water flow…
• 第 11.2.2 条Before the domestic water supply system piping is put into service, it must be flushed and disinfected, and s…
• 第 11.2.3 条The indoor drainage system shall undergo a flow capacity test: open 1/3 of the water supply system's distribu…
• 第 11.2.4 条The indoor drainage system shall undergo a ball passing test. The ball diameter shall be no less than 2/3 of …
• 第 11.3.1 条After the indoor heating system installation is completed, a hydrostatic test shall be conducted before pipe …
• 第 11.3.2 条After flushing is completed, the heating system shall be filled with water, heated, and subjected to trial op…
• 第 11.3.3 条During commissioning of the heating system, the indoor temperature of each loop and room in the system shall …
• 第 11.4.1 条After the hot water supply system is installed, a hydrostatic test shall be carried out before the pipeline i…
• 第 11.4.2 条After the hot water supply system is completed, it must be flushed.
• 第 11.4.3 条During commissioning of the hot water supply system, the water temperature at each distribution point of the …

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