Standard No.:	GB 50151-2021
English Name:	Technical standard for foam extinguishing systems
Chinese Name:	泡沫灭火系统技术标准
Professional Classification:	GB    National Standard
Issued by:	AQSIQ, MOHRUD
Issued on:	2021-04-09
Implemented on:	2021-10-1
Status:	valid
Superseding:	GB 50151-2010 Code for design of foam extinguishing systems GB 50281-2006 Code for installation and acceptance of foam extinguishing systems
Language:	English
File Format:	PDF
Word Count:	47500 words
Price(USD):	1300.0
Delivery:	via email in 1 business day

Technical standard for foam extinguishing systems 1 General provisions 1.0.1 This standard is formulated with a view to reasonably designing foam extinguishing systems to ensure their installation quality and use function, reduce fire hazards, and protect personal and property safety. 1.0.2 This standard is applicable to the design, installation, acceptance, and maintenance management of foam extinguishing systems arranged in the newly-built, renovated and expanded projects. This standard is not applicable to foam extinguishing systems arranged in places such as ships and offshore oil platforms. 1.0.3 No foam extinguishing system shall be used in places containing the following substances: 1 Chemicals and strong oxidants that can be rapidly oxidized even in an air-free environment, such as nitrocellulose and explosives; 2 Active metals and chemicals that will undergo hazardous chemical reaction when coming into contact with water, such as potassium, sodium, alkyl aluminum, and phosphorus pentoxide. 1.0.4 Air foam extinguishing systems should not be used for low-boiling point flammable liquid tanks for flammable liquids with boiling point < 45 °C and C5 and components below C5 with mole percentage ≥ 30%. 1.0.5 In addition to this standard, the design, installation, acceptance, maintenance and management of foam extinguishing systems shall also meet those stipulated in the current relevant standards of China.   2 Terms I General terms 2.0.1 foam concentrate concentrated liquid which can be mixed with water at an appropriate concentration to form foam solution 2.0.2 foam solution solution prepared with foam concentrate and water according to the specified concentration 2.0.3 premixed foam solution foam concentrate prepared in advance with foam concentrate and water according to the specified concentration and stored for later use 2.0.4 concentration volume percentage of foam concentrate in foam solution 2.0.5 foam expansion ratio ratio of the volume of foam to that of the foam solution from which it was made 2.0.6 low-expansion foam fire foam with a foam expansion ratio below 20 2.0.7 medium-expansion foam fire foam with a foam expansion ratio of 20 to 200 2.0.8 high-expansion foam fire foam with a foam expansion ratio above 200 2.0.9 application rate (density) supply amount of foam solution or water per unit time per unit area, expressed by “L/(min·m2)” 2.0.10 fixed system fire extinguishing system consisting of a fixed foam system water supply pump, a foam proportioner (proportioning set), a foam maker (or sprinkler) and pipes 2.0.11 semi-fixed system fire extinguishing system consisting of a fixed foam maker with partial connecting pipes, a foam fire truck or a portable fire pump and a foam proportioner, which are connected with water hoses 2.0.12 mobile system fire extinguishing system consisting of a fire truck, a portable fire pump or pressurized water source, a foam proportioner, foam nozzles, foam monitors or mobile foam makers, which are connected with water hoses 2.0.13 balanced pressure proportioning set proportioning set which can automatically control concentration within a certain range of flow pressure and flow, by using a separate foam concentrate supply pump to inject foam concentrate into the pressure stream at a set pressure difference, and then make it get through the balance valve, orifice plate or venturi (or a combination of an orifice plate and a venturi) 2.0.14 coupled water-turbine driven pump proportioning set proportioning set which has blade type or spiral water turbine connected with the foam concentrate supply pump by a coupling, uses the pressure water supplied by the foam system water supply pump to drive the water turbine, and then injects the foam concentrate with the foam concentrate supply pump into the foam fire fighting water pipe behind the water turbine at a set proportion 2.0.15 pump direct injection proportioning proportioning in which a foam concentrate supply pump directly injects the foam concentrate into the flow of the system at a set proportion 2.0.16 bladder pressure proportioning tank device in which pressure water uses orifice plate or venturi to discharges foam concentrate from the capsule of a closed tank and mixes it with water at a set proportion 2.0.17 in-line eductor venturi device installed on the water supply pipeline leading to the foam maker 2.0.18 air-aspirating discharge device device, designed based on the venturi principle, which can suck air into the foam solution to mix them to generate foam, and then spray out the foam in a specific mode, such as a foam maker, foam nozzle, foam monitor, and foam sprinkler 2.0.19 non air-aspirating discharge device device which has no air intake and uses aqueous film forming foam concentrate and other foam solution, with spraying mode similar to that of water spraying devices such as water gun, water monitor, and water-spaying sprinkler 2.0.20 foam system water supply pump fire pump supplying water for a foam extinguishing system   2.0.21 foam concentrate supply pump pump supplying foam concentrate for a foam extinguishing system 2.0.22 foam system pump station place where a foam system water supply pump is installed 2.0.23 foam station place without a foam system water supply pump, but with foam proportioning set(s), foam concentrate tanks, etc. II Terms of low-expansion foam extinguishing systems 2.0.24 surface application system fire extinguishing system which sprays foam from a location above the liquid surface into the protected tank 2.0.25 subsurface injection system fire extinguishing system which sprays foam from a location below the liquid surface into the protected tank 2.0.26 foam maker in standing position foam maker installed vertically on the shell of vertical tanks for Class A, B or C liquids 2.0.27 foam maker in horizontal position foam maker installed horizontally on the open-top floating roof tank 2.0.28 high back-pressure foam maker device which introduces air into the compressed foam solution for generating low-expansion foam, with a certain pressure (gauge pressure) at the outlet 2.0.29 foam guiding cover device installed on the top of the shell of open-top floating roof tank to make foam flow down the tank shell, thus preventing foam loss 2.0.30 foam buffering cover device installed at the outlet of a foam maker of fixed roof tank or covered floating roof tank to guide foam to slowly release to the surface of water-soluble liquid or single and double-deck annular sealing area along the tank shell III Terms of medium and high-expansion foam extinguishing systems 2.0.31 total flooding system fire extinguishing system spraying foam with stationary foam maker, directly or via a foam distribution duct, to a protected area sealed or enclosed, where the foam reaches a certain flooding depth within a specified period of time 2.0.32 local application system fire extinguishing system spraying foam with stationary foam maker, directly or via a foam distribution duct, to a fire site 2.0.33 enclosure space enclosed by difficult-combustible or non-combustible components 2.0.34 foam application rate total volume of foam supplied per unit time, expressed in m3/min 2.0.35 foam distribution duct distribution duct conveying high-expansion foam from the outlet of the foam maker to a protected area IV Terms of foam-water sprinkler systems and foam spray systems 2.0.36 foam-water sprinkler system automatic fire extinguishing system which can automatically spray foam and water in turn to a protected area at predetermined application rate as scheduled in case of fire, consisting of components such as sprinkler, alarm valve group, water flow alarm equipment (water flow indicator or pressure switch), together with pipe, foam concentrate and water supply devices

Foreword i 1 General provisions 2 Terms 3 Foam concentrate and system components 3.1 General requirements 3.2 Selection and storage of foam concentrate 3.3 Foam system water supply pump and foam concentrate supply pump 3.4 Foam proportioners (proportioning sets) 3.5 Foam concentrate tanks 3.6 Foam generating devices 3.7 Control valves and piping 4 Low-expansion foam extinguishing systems 4.1 General requirements 4.2 Fixed roof tanks 4.3 Open-top floating roof tanks 4.4 Covered floating roof tanks 4.5 Other places 5 Medium and high-expansion foam extinguishing systems 5.1 General requirements 5.2 Total flooding system 5.3 Local application systems 5.4 Mobile systems 6 Foam-water sprinkler systems and foam spray systems 6.1 General requirements 6.2 Foam-water deluge systems 6.3 Closed-head foam-water sprinkler systems 6.4 Foam spray systems 7 Foam system pump station and water supply 7.1 Foam system pump station and foam station 7.2 Water supply for systems 8 Hydraulic calculation 8.1 Design flow of systems 8.2 Hydraulic calculation of pipes 8.3 Decompression methods 9 System installation 9.1 General requirements 9.2 Field inspection 9.3 Installation 9.4 Commissioning 10 Acceptance 11 Maintenance management Annex A Engineering division of the foam extinguishing system Annex B Installation and acceptance records of the foam extinguishing system Annex C Measurement method of the foam expansion ratio Annex D Maintenance management records of the foam extinguishing system Explanation of wording in this standard List of quoted standards