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GB 4351-2023: Portable fire extinguishers
GB 4351-2023
GB
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
ICS 13.220.10
CCS C 84
Replacing GB 4351.1-2005, GB 4351.2-2005, GB/T 4351.3-2005
Portable fire extinguishers
手提式灭火器
ISSUED ON: DECEMBER 28, 2023
IMPLEMENTED ON: JANUARY 01, 2025
Issued by: State Administration for Market Regulation;
Standardization Administration of the People's Republic of China.
Table of Contents
Foreword ... 4
1 Scope ... 7
2 Normative references ... 7
3 Terms and definitions ... 8
4 Classification and model ... 11
4.1 Classification ... 11
4.2 Model ... 11
5 Performance requirements for fire extinguishers ... 12
5.1 Operating temperature range ... 12
5.2 Filling requirements ... 12
5.3 Discharge performance ... 13
5.4 Mechanical properties ... 15
5.5 Sealing performance ... 15
5.6 Corrosion resistance ... 16
5.7 Fire extinguishing performance ... 17
5.8 Electrical insulation properties ... 18
6 Performance requirements for fire extinguisher components ... 19
6.1 Cylinder ... 19
6.2 Fire extinguisher valve assembly ... 19
6.3 Safety device ... 20
6.4 Pressure gauge ... 20
6.5 Discharge hose ... 20
6.6 Filters for water-based fire extinguishers ... 21
6.7 Rubber sealing ring ... 22
6.8 Plastic parts ... 22
6.9 Fixing bracket ... 22
6.10 Fire extinguishing agents ... 23
6.11 Propellant ... 23
7 Test methods for fire extinguishers ... 23
7.1 Fill inspection ... 23
7.2 Discharge performance test ... 24
7.3 Mechanical properties test ... 26
7.4 Sealing performance test ... 28
7.5 Corrosion resistance test ... 29
7.6 Fire extinguishing performance test ... 31
7.7 Electrical insulation performance test ... 40
8 Test methods for fire extinguisher components ... 41
8.1 Cylinder test ... 41
8.2 Test of fire extinguisher valve assembly test ... 41
Portable fire extinguishers
1 Scope
This document gives the terms and definitions, classification and models of portable
fire extinguishers (hereinafter referred to as fire extinguishers). It specifies the
performance requirements, colors and marks, manuals, inspection rules, packaging,
transportation and storage of portable fire extinguishers and components. It describes
the test methods.
This document applies to the design, manufacture and inspection of portable fire
extinguishers and their components used in industrial and civil buildings.
2 Normative references
The following referenced documents are indispensable for the application of this
document. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
GB/T 192, General purpose metric screw threads -- Basic profile
GB/T 193, General purpose metric screw threads -- General plan
GB/T 196, General Purpose Metric Screw Threads -- Basic Dimensions
GB/T 197, General purpose metric screw threads -- Tolerances
GB/T 1804, General tolerances -- Tolerance for linear and angular dimensions
without individual tolerance indications
GB/T 2516, General purpose metric screw threads -- Limit deviations
GB/T 2828.1, Sampling procedures for inspection by attributes -- Part 1: Sampling
schemes indexed by acceptance quality limit (AQL) for lot-by-lot inspection
GB/T 3181, Colour standard for paint film
GB 4066, Powder extinguishing agent
GB 4396, Carbon dioxide extinguishing agent
GB/T 4423, Copper and copper alloy cold-drawn rod and bar
GB/T 4968, Classification of fires
is 60℃, the effective discharge time shall not exceed the average effective discharge
time when the operating temperature is 20℃. The effective discharge time at the lowest
operating temperature shall not exceed 2.5 times the average effective discharge time
at 20℃.
5.3.2.2 The delayed-action time of discharge of the fire extinguisher shall not be greater
than 5 s.
5.3.2.3 The rate of residual extinguishing medium of the fire extinguisher shall not be
greater than 10%.
5.3.3 Intermittent discharge performance
The discharging of fire extinguishers shall be interrupted at any time. The delayed-
action time of discharge of the first discharging of fire extinguishers shall not be greater
than 5 s. The delayed-action time of discharge of subsequent intermittent discharging
shall not be greater than 1 s. The rate of residual extinguishing medium of fire
extinguishers shall not be greater than 10%.
5.3.4 Post-vibration discharge performance of dry powder fire extinguisher
After the dry powder fire extinguisher has been subjected to the vibration test, it shall
be able to operate normally. The delayed-action time of discharge shall not be greater
than 5 s. The rate of residual extinguishing medium shall not be greater than 10%.
5.4 Mechanical properties
5.4.1 Impact resistance
After the impact resistance test, the fire extinguisher shall not explode, rupture or have
parts ejected.
5.4.2 Vibration resistance
After the vibration resistance test, the fire extinguisher and its components shall not fall
off, crack or deform significantly. The effective discharge time, delayed-action time of
discharge, rate of residual extinguishing medium and bulk range of the fire extinguisher
shall meet the requirements of 5.3.1.
5.5 Sealing performance
5.5.1 Storage sealing performance
5.5.1.1 Gas cylinder fire extinguisher: The annual leakage rate or annual leakage
volume of the gas cylinder shall not be greater than the smaller value between 5% and
7 g of the mass of the gas in the cylinder.
6.5.3 Pressure resistance
6.5.3.1 The burst pressure of a discharge hose assembly equipped with a nozzle with a
switch shall be greater than or equal to the following values:
- When the test temperature is (20±5)℃, 3 times the maximum service pressure;
- When the test temperature is (60±2)℃, 2 times the maximum service pressure.
6.5.3.2 The burst pressure of the discharge hose assembly of the carbon dioxide fire
extinguisher shall be greater than or equal to the following value:
- When the test temperature is (20±5)℃, 1.5 times the maximum service pressure;
- When the test temperature is (60±2)℃, 1.25 times the maximum service pressure.
6.5.3.3 A discharge hose assembly equipped with a nozzle without a switch shall be
able to withstand the test pressure of the fire extinguisher for more than 30 s without
leakage.
6.5.4 Low temperature bending performance
6.5.4.1 After the low temperature bending performance test, the lining and outer surface
of the discharge hose shall not be broken.
6.5.4.2 After the water pressure test, the discharge hose shall not leak.
6.5.5 Requirements for nozzles and horns of carbon dioxide fire extinguishers
6.5.5.1 2 kg and 3 kg carbon dioxide fire extinguishers shall use rigidly connected
nozzles. The rigidly connected nozzles shall be able to rotate around the valve joint and
stop at any position.
6.5.5.2 The connection between the discharge hose and the horn of 5 kg and 7 kg carbon
dioxide fire extinguishers shall be equipped with a handle made of dry hard wood that
can withstand low temperatures of -50°C, is heat-insulating and anti-static.
6.5.5.3 After testing, the horn of the carbon dioxide fire extinguisher shall be able to
withstand compression and shall not show any cracking or damage.
6.6 Filters for water-based fire extinguishers
6.6.1 The filter of water-based fire extinguishers shall be made of materials resistant to
corrosion by fire extinguishing agents.
6.6.2 Water-based fire extinguishing agents shall be discharged through a filter. The
filter shall be placed upstream of the smallest section of the discharge channel. The area
of each hole in the filter shall be less than the minimum cross-sectional area of the
discharge channel. The sum of the areas of all holes in the filter shall not be less than 8
times the minimum cross-sectional area of the discharge channel. The installation of the
filter shall facilitate the maintenance of the fire extinguisher.
6.7 Rubber sealing ring
6.7.1 After aging and heat resistance tests, the rubber sealing ring shall not be cracked
or deformed.
6.7.2 After low temperature test, the rubber sealing ring shall not be cracked or
deformed.
6.8 Plastic parts
6.8.1 General requirements
A raw material quality assurance certificate provided by the plastic parts manufacturer
shall be provided.
6.8.2 Heat resistance
6.8.2.1 After the heat resistance test, the plastic parts used in the fire extinguisher shall
not be damaged by cracking, deformation, etc.
6.8.2.2 After the vibration test, the fire extinguisher shall meet 5.4.2.
6.8.3 Fire extinguishing agent resistance
After being soaked in fire extinguishing agent, the attenuation rate of the material
deformation force of the siphon tube ring specimen shall not be greater than 40%.
6.8.4 Anti-ultraviolet light aging performance
After the ultraviolet light aging test, the external plastic parts shall not have cracks.
6.9 Fixing bracket
6.9.1 The hook of the fire extinguisher shall be such that the original fire extinguisher
can only be removed from the wall after it has moved at least 6 mm in the horizontal or
vertical direction. For fire extinguishers with a total mass greater than or equal to 5 kg,
the minimum vertical movement is 3 mm.
6.9.2 The fixing bracket shall be able to withstand a static load of 5 times the total mass
of the fully charged fire extinguisher, and not less than 45 kg. After the test, the fixing
bracket shall not have defects such as breakage and obvious deformation.
accordance with the method in 7.2.1.1.
7.2 Discharge performance test
7.2.1 Discharge performance test at 20°C
7.2.1.1 Effective discharge time, delayed-action time of discharge, rate of residual
extinguishing medium
Take 3 fire extinguishers for testing. The fire extinguishers shall be placed in an upright
position in a (20±5)℃ environment for at least 18 h. Then take out the fire extinguishers.
The following tests shall be carried out within 2 min:
a) Fix the fire extinguisher on the discharge test device. Remove the safety device
of the fire extinguisher. Wait for the test device to remain stationary for 6 s;
b) Read and record the mass of the fire extinguisher;
c) Start the discharge test device to discharge. Read and record the delayed-action
time of discharge and effective discharge time during the discharging process of
the fire extinguisher;
d) For gas cylinder fire extinguishers, start the gas cylinder first to release the
pressure. After 6 s, start the discharge test device to discharge;
e) For carbon dioxide fire extinguishers and clean gas fire extinguishers, weigh them
immediately after discharging. Empty the remaining fire extinguishing agent and
weigh them again. Then fill the cylinder with water. Measure the volume of the
cylinder. Record and calculate the rate of residual extinguishing medium, filling
amount, fill error and fill density;
f) For dry powder fire extinguishers and water-based fire extinguishers, weigh them
after discharging. Then empty the remaining fire extinguishing agent. Weigh them
again after emptying. Record and calculate the rate of residual extinguishing
medium, mass filling amount, and fill error;
g) For water-based fire extinguishers, pre-measure the density of the water-based
fire extinguishing agent filled at 20°C. After operating according to f), calculate
the volume filling amount and fill error from the mass filling amount.
7.2.1.2 Bulk range
The test shall be carried out in a well-lit room. Use a black background to mark the
horizontal distance. Place the fire extinguisher in an environment of (20±5)℃ for at
least 18 hours. After taking it out, operate according to 7.2.1.1a) within 2 minutes. Then
start the device to discharge. When discharging, the nozzle of the fire extinguisher shall
be kept horizontal. The center of the nozzle shall be at least 1m above the ground. When
b) Store the two fire extinguishers at the lowest operating temperature ±2℃ for at
least 18 h. Within 2 min after taking them out, each fire extinguisher shall be
tested in the manner specified in c) and d).
c) Place the fire extinguisher on a hard surface in the following two ways:
- When the fire extinguisher is in a normal upright position, the steel hammer and
the valve axis in the vertical direction coincide;
- When the fire extinguisher is in a flat position, the valve pillow is placed on the
steel block, so that the steel hammer is located on the vertical line of the valve
center.
d) In the above two methods, the steel hammer is allowed to fall vertically freely
from a height of h to impact the valve of the fire extinguisher.
e) For gas cylinder type fire extinguishers, the fire extinguisher shall be placed under
pressure during the test.
7.3.2 Vibration resistance test
7.3.2.1 The fire extinguisher shall be fixed in the fixture of the vibration table in an
upright position. For fire extinguishers with special fixing frames, install the fire
extinguisher in the fixing frame. Then fix the fixing frame in the fixture of the vibration
table.
7.3.2.2 Fire extinguishers not for vehicle use shall be tested in accordance with the
method in 7.3.2.3. Fire extinguishers suitable for vehicle use shall be tested in
accordance with the method in 7.3.2.4.
7.3.2.3 For non-vehicle fire extinguishers, change the vibration direction of the
vibration table in sequence. The fire extinguisher shall be vibrated along the horizontal,
lateral and vertical linear axes respectively. The vibration test in each direction shall be
carried out according to the following parameters:
- Frequency is 40 Hz;
- Amplitude is (0.25±0.03) mm;
- Duration is 2 h.
7.3.2.4 For vehicle fire extinguishers, the test shall be carried out in the following
manner:
a) Change the vibration direction of the vibration table in sequence, so that the fire
extinguisher vibrates along the horizontal, lateral and vertical linear axes
respectively. After completing the tests b) and c) in one d...