GB 15308-2025Foam extinguishing agent (English PDF)

5.1 General requirements

5.1.1 If the foam concentrate is suitable for use with seawater, the concentration of the foam solution prepared with seawater shall be the same as that prepared with fresh water.

5.1.2 The raw materials and production process of the foam concentrate shall meet the requirements of human health, safety and environmental protection.

5.1.3 Foam concentrates of different model specifications or produced by different processes shall not be mixed when filling fire extinguishers, fire trucks and fire extinguishing systems are filled or when fire extinguishing equipment is repaired.

5.2.1 Low expansion foam concentrate

5.2.1.1 The physical and chemical properties of low expansion foam concentrate or foam solution shall comply with the requirements of Table 2.

6.1 Sampling and temperature treatment

6.1.1 Sampling Whether sampling from one container or from multiple containers, stir thoroughly. Fill the storage container with the sample and seal it.

6.1.2 Temperature treatment The foam concentrate shall be temperature-treated according to the following steps.

a) If the manufacturer declares that the sample is not affected by freeze-thaw, the sample shall first be subjected to four freeze-thaw cycles according to 6.3, and then processed according to 6.1.2b);

b) Place the sample sealed in the container in an environment at (60±2) °C for 7 days, and then place it in an environment at (20±5) °C for 1 day;

c) If the manufacturer declares that the sample is subject to freeze-thaw, only process the sample according to 6.1.2b).

6.2 Freezing point

6.2.1 Instruments and equipment Test instruments and equipment shall meet the following requirements.

a) Freezing point test equipment. with a temperature control accuracy of ±1 °C;

b) Platinum resistor. T100, with an accuracy of ±0.1 °C and an outer diameter of

c) Digital temperature display instrument. The resolution is 0.1 °C.

6.2.2 Test steps The freezing point test for the foam concentrate shall be carried out according to the following steps.

a) Turn on the freezing point test equipment and stabilize the temperature of the cold chamber at (10±1) °C below the freezing point of the sample;

b) Inject the sample into the dry, clean inner tube so that the liquid level is approximately 50 mm;

c) Use a cork or rubber stopper to fix the platinum resistor in the center of the inner tube, with the lower end of the platinum resistor 10 mm away from the sample liquid surface;

d) Place the inner tube containing the sample into the outer tube, with the distance from the bottom of the inner tube to the bottom of the outer tube not exceeding 10 mm. Then place the outer tube into the cold chamber, with the depth of the outer tube in the cold chamber not less than 100 mm.

e) Start the test, and the equipment automatically records the temperature-time curve;

f) When the sample is completely frozen, read the temperature at the platform of the curve as the freezing point;

g) Repeat the test and take the higher value of the two test results with a difference of no more than 1 °C as the measurement result.

6.3 Freeze and thaw resistance

6.3.1 Instruments and equipment Low-temperature box. It can meet the temperature requirements of 6.3.2b).

6.3.2 Test steps The foam concentrate shall be tested for freeze and thaw resistance properties according to the following steps.

a) Determine the freezing point of the sample according to 6.2.2;

b) Adjust the temperature of the low-temperature box to (10±1) °C below the freezing point of the sample;

c) Place the sample that meets the requirements of

6.1.1 into a plastic or glass container, seal it, and place it in a low-temperature box. Keep it at the temperature specified in 6.3.2b) for 24 hours. After freezing, remove the sample and place it at a room temperature of (20±5) °C for (24~96) hours. Repeat this process three more times, for a total of four freeze-thaw cycles.

d) Observe the sample for stratification and heterogeneity.

6.4 Sediment

6.4.1 Instruments and equipment Test instruments and equipment shall meet the following requirements.

a) Electric centrifuge. The centrifugal acceleration is (6000±600) m/s2;

b) Graduated centrifuge test tube. with a capacity of 50 mL and a minimum graduation value of

0.1 mL;

c) Sieve. It is in accordance with the requirements of GB/T 6003.1, with a pore size of 180 µm;

d) Electric blast drying oven. with a temperature control accuracy of ±2 °C;

e) Stopwatch. with a graduation value of

0.1 seconds.