Water Fire Extinguisher

Dry Powder Extinguisher

Separation

• Examine the extinguisher body internally and externally for corrosion and damaged conditions with illuminating probe. Damaged and corroded extinguisher should be removed from service. Corroded Gas Cartridge should also be replaced.

• Examine the gas cartridge for mass. If there is loss of more than 10 percent of original mass, the cartridge should be sent for-recharging after being replaced by a charged one. For re-charging procedure given in 12.4 should be followed.

• Examine nozzle, strainer, vent holes, internal discharge tube, sealing washer, replace them if not in good condition. Otherwise clean them thoroughly.

• Check the operating mechanism for free movement and piercing mechanism if working properly.

• Refill the fire extinguisher with clean water.

• Open the extinguisher, check the liquid level. Pour liquid in separate clean receptacle to see if there is any sediment at the bottom of the cylinder reject the charge if there is sufficient sludge formation.

• Examine the extinguisher externally and internally for any corrosion or damage. Damaged and corroded extinguisher should be removed from service. Corroded gas cartridge should also be replaced.

• Examine the foam generating nozzle, strainer, vent hoes, internal discharge tube ceiling washer, etc. replace them, if not in good condition. Otherwise clean them thoroughly.

• Check the operating mechanism for free movement and piercing mechanism for proper working.

• Clean the hose assembly and check it for any dust/sediment at either shank ends.

• All dry powder extinguisher should be inspected and maintained in accordance with the following. The dray powder extinguishers should be opened in a dry room and for a minimum possible time to avoid to atmospheric moisture on powder.

• Dry powder extinguisher where discharges control is fitted on the nozzle, should be operated before opening the extinguisher to ensure that there is no pressure in the extinguisher.

• Weight the extinguisher to check correct mass of powder filled in it which should be marked on the body of extinguisher and record book when it was first put into service.

• Open the extinguisher and remove gas cartridge and see that sealing disc is intact. Weight and compare its mass with full mass of cartridge marked on it. In case, loss of mass I more than 10 percent it should be replaced by new cartridge.

• Check the operating mechanism, discharge control for free movement and closing. Examine nozzle, hose vent holes, piercing mechanism of cap cartridge holder grease and wipe clean.

• Remove the inner shell (if any) and clean port holes.

• Empty the dry powder in a dry container and examine for caking lumps and foreign matter in which case replace it with new dry powder charge.

• Examine the extinguisher body internally for any damage or corrosion and replace corroded or damaged extinguisher.

• Clean the extinguisher using dry air.

• Return the original charge to the extinguisher and fit the cartridge and other fittings.

• In case of higher capacity dry powder fire extinguisher as per IS 10658 remove the carbon dioxide cylinder and check the weight marked on the cylinder to ensure that the size conforms to that stipulated in the specification. On weighing if the loss of mass is more than 10 percent it should be sent for recharging. Also examine the wheel carriage and discharge hose assembly with control nozzle for free flow and test it with dry air.

• In case of dry powder extinguisher for metal fires as per IS 11833, in addition to item 10 above, examine the applicator pipe and the discharge shower head for freedom from clogging and clean it with dry air. Sample of the dry powder for metal fire may be tested on a small fire of magnesium turning or chips to ensure that the powder is suitable for metallic fire risks.

• The safety valves and pressure gauges fitted on higher capacity extinguisher should be calibrated once in 3 years and recorded in the register.