1 General Provisions
1.0.1 This code is formulated with a view to correctly and rationally design automatic fire sprinkler systems and to provide protection for life and property from fire.
1.0.2 This code is applicable to the design of the automatic fire sprinkler systems in the newly built, expanded and rebuilt civil and industrial buildings.
This code is not applicable to the design of the automatic fire sprinkler systems in occupancies with special functions such as gunpowder, explosive, ammunition factories, nuclear power stations and aircraft hangars and so on.
1.0.3 The design of automatic fire sprinkler systems shall be based on the functions and fire risks of the occupancies. The selection of automatic fire -sprinkler systems shall be proper to provide reliable, economical, and advanced fire protection.
1.0.4 The system components of the design must comply with the existing relevant standards, and must pass the test done in National Center for Quality Supervision and Test of Fixed Fire-fighting Systems and Fire-resisting Building Components.
1.0.5 In case that the purposes of the occupancies with the designed automatic sprin¬kler systems are changed, the applicability of existing systems should be collated and examined. In case that the systems are inapplicable, the systems shall be redisigned according to this code.
1.0.6 The design of automatic fire sprinkler systems shall comply with not only this code but also the compulsory requirements of current relevant national design codes and standards.
2 Terms and Symbols
2.1 Terms
2.1.1 Sprinkler Systems
Consisting of sprinkler, alarm valves, waterflow device (waterflow indicator or pressure switch) as well as pipes and water supplying facilities, a sprinkler system can automatically spray out water in case of fire.
2.1.2 Close-type Sprinkler System
An automatic sprinkler system that adopts close-type sprinkler heads.
1 Wet Pipe System
A close-type system in which pipes are filled with pressed water when the system is in the pre-working condition.
2 Dry Pipe System
A close-type system in which pipes are filled with pressed air when the system is in the pre-working condition.
3 Preaction System
A system in which no water shall be filled in the feed mains and it can be switched into wet pipe system after the automatic fire alarm system opens deluge-alarm valve.
4 Recycling Preaction System
A preaction system that can automatically close valves after the fire is put off and open spraying valve when the fire is on again.
2.1.3 Deluge System
An automatic sprinkler system that is controlled by automatic fire alarm system or transmission pipe and that can automatically supply water to the open-type sprinkler after the deluge alarm system and water supply valve are opened automatically. This system is also called open-style system.
2.1.4 Drencher Systems
A water spray system that consists of open-type spray heads or drencher spray heads, deluge alarm valves or temperature sensing deluge valves and waterflow devices (waterflow indicator or pressure switch). It is used in smoke and fire stopping and cooling partitions.
1 Water curtain for fire compartment
Drencher that forms water wall or water curtain with dense water spraying.
2 Drencher for cooling protection
Drencher of the compartments such as cooling fire protection curtain and so on.
2.1.5 Combined sprinkler-foam system
An automatic sprinkler system that either sprays water or foam after installing de¬vices that supply foam combined liquid.
2.1.6 Area of sprinklers operation
The maximum area that is protected based on the discharge density in a fire acci¬dent.
2.1.7 Standard sprinkler
Sprinklers with flow rate factor of K=80.
2.1.8 Response time index (RTI)
Heat sensibility performances of close type sprinkler.
2.1.9 Fast response sprinkler
Close-type sprinklers with the response time index RTI≤50 (m·s)0.5.
2.1.10 Extended coverage sidewall sprinkler
Sidewall fast response sprinklers with the flow rate factors of K=115.
2.1.11 Early suppression fast response sprinkler (ESFR)
Large flow rate special sprinklers with the RTI≤28±8 (m·s)0.5 and used to pro¬tect high stow or high rack warehouses.
2.1.12 Area of one sprinkler operation
Product of the distance between adjacent sprinklers on the same branch line and the distance between adjacent branch lines.
2.1.13 End mains
The pipes supplying water to cross lines after alarm valve.
2.1.14 Feed mains
The pipes supplying water to branch lines.
2.1.15 Branch lines
Pipes supplying water directly or through sprig-ups to sprinklers.
2.1.16 System pipes
A general term for feed mains, cross mains and branch lines.
2.1.17 Sprig-up
Vertical pipes connecting sprinklers and branch lines.
2.1.18 Signal valve
Valve with the function to give signals to indicate open or close condition.
2.2 Symbols
a——Horizontal space between sprinkler and obstruction;
b——Vertical space between sprinkler deflector and the underside of obstruction;
c——Length of one side of the cross section of obstruction;
d——Outside diameter of pipe;
dg——Calculated inside diameter of throttle pipe;
dj——Calculated inside diameter of pipe;
dk——Inside diameter of hole on pressure-reducing orifice;
e——Length of another side of the cross section of obstruction;
f——Vertical space between sprinkler deflector and top surface of the Non-full height partition;
g——Acceleration of gravity;
h——Pipe friction loss and local friction loss;
H——Water pressure at the pump lift or system entrance;
Hg——Friction loss of throttle plpe;
Hk——Friction loss of pressure-reducing orifice;
i——Friction loss of the pipe per meter;
K——Sprinkler flow rate factor;
L——Length of throttle pipe;
n——Number of sprinklers in the operating area at most hydraulically remote posi¬tion;
P——Sprinkler working pressure;
Po——Working pressure of the most hydraulically remote sprinkler;
q——Flow rate of sprinkler;
qi——Flow rate of the sprinkler knot within the operating area of at the most hydraulically remote position;
Qs——Design flow rate;
V——Average flow velocity of the water in pipe;
Vg——Average flow velocity of the water in throttle pipe;
Vk——Average flow velocity of water in pipe behind pressure-reducing orifice;
Z——Difference of elevations of the most hydraulically remote sprinkler and the lowest level of fire pool or the plane central line of system entrance line;
ζ——gum of local resistance factors of gradual shrinking pipe and gradual expanding pipe in the throttle pipe;
ξ——Local resistance factor of pressure-reducing orifice.
3 Hazard Classifications of Occupancies
3.0.1 The hazard classifications of occupancies should comply with the following requirements:
1 Light hazard
2 Ordinary hazard
Class Ⅰ
Class Ⅱ
3 Extra hazard
Class Ⅰ
Class Ⅱ
4 Warehouse hazard classification
Class Ⅰ
Class Ⅱ
Class Ⅲ
3.0.2 The hazard classifications of occupancies should be determined after analyzing the fire features and the difficulty levels of the hot air stream to open the sprinkler and make it discharge water to the designed position. And the determination also shall be based on factors such as purposes, fire loads of the contents and indoor space condition etc. See Appendix A of this code for examples.
3.0.3 In case of big differences between fire hazards and fighting difficulties of the sites in the buildings, system selection and fire hazard classifications should be deter¬mined according to the actual conditions of each site.
4 System Selection
4.1 General Requirements
4.1.1 Automatic sprinkler systems should be equipped within the places with large population, hard evacuation, difficult for outside assistance and rescue or serious fire hazard.
4.1.2 Automatic sprinkler system is inapplicable to the places with the following arti¬cles:
1 Articles can explode or their burning can be accelerated when contacting with water;
2 Articles with the possibility to cause serious chemical reaction or produce haz¬ardous articles with water;
3 Liquids can cause spurts or boiling when sprinkled water.
4.1.3 The system selection of automatic sprinkler system shall be determined accord¬ing to the fire features or environmental conditions of the occupancies. Close type sys¬tem is inapplicable to the outdoor places.
4.1.4 The design principle of the automatic sprinkler system shall meet the following provisions:
1 Fire detectors of close-type sprinkler or startup system shall effectively detect fires at the initial stage;
2 Wet pipe system and dry pipe system shall be started up after one sprinkler is opened, and the preaction system and deluge system should be started up after the auto¬matic fire alarm system alarmed.
3 The sprinklers within the operating areas shall continuously spray water with selected intensity in prescribed time;
4 The water sprayed by sprinklers should be average and not be suffocated.
4.2 System Selection
4.2.1 For occupancies with ambient temperature not lower than 4℃ and not higher than 70℃, wet pipe systems shall be adopted.
4.2.2 For occupancies with ambient temperature lower than 4℃ or higher than 70℃, dry pipe systems shall be adopted.
4.2.3 For occupancies with one of the following requirements, preaction system shall be adopted:
1 Water leakage is strictly prohibited when the system is in the pre-working con¬ditions;
2 False spraying of system is strictly prohibited;
3 Dry pipe system is replaced.
4.2.4 For the occupancies where water spraying should be stopped timely after the fire is put out, recycling preaction system shall be adopted.
4.2.5 For occupancies with one of the following requirements, deluge system shall be adopted:
1 The area where the horizontal spreading of fire is fast and the fire cannot be covered effectively by the spraying water of the close-type sprinkler;
2 The indoor clear height exceeds the prescription in Article 6.1.1 and the fire must be put out at the initial stage;
3 With the hazard as extra hazard Ⅱ.
4.2.6 When automatic sprinkler system is provided in the warehouses that meet the prescriptions in article 5.0.6 of this code, early suppression fast response sprinkler and wet pipe system should be adopted.
4.2.7 As for the occupancies with large amount of flammable liquids, the combined sprinkler-foam system should be adopted in one of the following manners:
1 To strengthen the performances of close-type system by adopting foam extin¬guishing agents;
2 The deluge system prays water to extinguish fire at the initial stage, and then sprays foam to enforce fire suppression effect.
3 The deluge system prays foam to extinguish fire at the initial stage, and then prays cool water to prevent burn-back.
The selection and storage of foam extinguish agents and the employment of relevant equipment shall be in accordance with the current national standard “Code for Design of Low Multiple Foam Extinguish System” GB 50151—92.
4.2.8 The dry pipe system, preaction system, deluge system and the combined sprin-kler-foam system of the local occupancies may be connected with the wet pipe system of the same occupancies and shall be also connected with the feed mains.
4.2.9 The sprinkler system should include the following parts, components and facili¬ties:
1 Sprinkler, waterflow indicator, alarm valve, pressure valves and end water test device, as well as pipes and water supply facilities;
2 The sections which control the pipe static pressure should be supplied or equipped with pressure-reducing valves, while the sections which control the pipe dy¬namic pressure should be equipped with pressure-reducing orifices or throttle pipes;
3 Discharge valve (discharge gap), exhaust valve (exhaust gap) and drain holes;
4 Fast exhaust valves shall be provided on the pipes in dry pipe system and preac¬tion system. As for pressure air pipes, electrical valves shall be provided before the en¬trance of the fast exhaust valves.
4.2.10 Protecting and cooling drencher should directly spray water onto the protecting targets; water curtain for fire compartment should not be applicable to openings (except for arena opening) with the size exceeding 15m (width)×8m (height).
1 General Provisions
2 Terms and Symbols
2.1 Terms
2.2 Symbols
3 Hazard Classifications of Occupancies
4 System Selection
4.1 General Requirements
4.2 System Selection
5 Basic Design Parameters
6 System Components
6.1 Sprinklers
6.2 Alarm Valve
6.3 Waterflow Indicator
6.5 End Water Test Device
7 Sprinklers Arrangement
7.1 General Requirements
7.2 Distance between Sprinkler and Obstruction
8 Pipe
9 Hydraulic Calculation
9.1 Design Flow Rate of System
9.2 Hydraulic Calculation of Pipes
9.3 Pressure-reducing Measures
10 Water Supply
10.1 General Requirements
10.2 Water Pump
10.3 Water Tanks
10.4 Siamese Connections
11 Operation and Control
12 Local Application System
Appendix A Examples of Classifications of Occupancies
Appendix B Examples of Classifications of Plastics and Rubbers
Appendix C List of Equivalent Lengths
Appendix D Local Resistance Factor of Pressure-reducing Orifice
Explanation of Wording in This Code
