- All rechargeable-type fire extinguishers shall be recharged after any use or as indicated by an inspection or when performing maintenance. Extinguishers which are out of service for maintenance or recharging should be replaced by extinguisher(s) having the same class and at least equal rating. In no case, extinguishers of other facility should be withdrawn for this purpose.
- When performing or recharging, the recommendations of the manufacturer shall be followed.
- The amount of recharge agent shall be verified by weighing. The recharged gross mass shall be the same as the gross mass that is marked on the label. For those fire extinguishers that do not have the gross mass marked on the label, a permanent label that indicates the gross mass shall be affixed to the cylinder. The label containing the gross weight shall be a durable material of a pressure-sensitive, self-destruct type.
- Conversion of Fire Extinguisher Types
No fire extinguisher shall be converted from one typeto another, or shall any fire extinguisher be convertedto use a different type of extinguishing agent. Fireextinguishers shall not be used for any other purpose than that of a fire extinguisher.
- Leak Test
After recharging, a leak test shall be performed onstored-pressure and self-expelling types of fireextinguishers.
- Pump Tank (Every 12 months)
Pump tank water and pump tank calcium chloride based anti-freeze types of fire extinguishers shall be recharged with new chemicals or water, as applicable.
- Wetting Agent
The agent in stored-pressure wetting agent fireextinguishers shall be replaced annually. Only theagent specified on the nameplate shall be used forrecharging. The use of water or other agents isprohibited.
- AFFF and FFFP
The premixed agent in liquid charge-type AFFF(Aqueous Film-Forming Foam) and FFFP (Film-FormingFluoro-Protein Foam) fire extinguishers shall bereplaced at least once every year. The agent in solidcharge-type AFFF fire extinguishers shall be replacedonce every 5 years.
- 3 Procedures
- Recharge Agents
Only those agents specified on the nameplate or agentsproven to have equal chemical composition, physicalcharacteristics, and fire extinguishing capabilities shallbe used. Agents listed specifically for use with thatfire extinguisher shall be considered to meet theserequirements.
- Mixing of Dry Chemicals
Multipurpose BC or ABC dry chemicals shall not bemixed with alkaline-based dry chemicals.
- Topping Off
The remaining dry chemical in a discharged fireextinguisher shall be permitted to be re-used, providedthat it is thoroughly checked for the proper type,contamination, and condition. Dry chemical found tobe of the wrong type, or contaminated, shall not be reused.
- Dry Chemical Agent Re-use
Fire extinguishers removed after 5 years formaintenance or hydrostatic testing shall be emptied.The dry chemical agent shall be permitted to be reused,provided a closed recovery system is used andthe agent is stored in a sealed container to preventcontamination. Prior to re-use, the dry chemical shall be thoroughly checked for the proper type,contamination, and condition. Where doubt exists with respect to the type, contamination, or condition of the dry chemical, the dry chemical shall be discarded.
- Dry Powder
Pails or drums containing dry powder agents for scoopor shovel application for use on metal fires shall bekept full and covered at all times. The dry powder shallbe replaced if found damp.
- Removal of Moisture
For all non-water types of fire extinguishers, anymoisture shall be removed before recharging.
- Halogenated Agent
Halogenated agent fire extinguishers shall be chargedonly with the proper type and weight of agent asspecified on the nameplate.
- Halogenated Agent Re-use
The removal of Halon 1211 from fire extinguishersshall be done only using a listed halon closed recoverysystem. The removal of agent from other halogenatedagent fire extinguishers shall be done only using aclosed recovery system. The fire extinguisher shall beexamined internally for contamination or corrosion,or both. The halogenated agent retained in the systemrecovery cylinder shall be re-used only, if no evidenceof internal contamination is observed in the fireextinguisher cylinder. Halogenated agent removedfrom fire extinguishers that exhibit evidence of internalcontamination or corrosion shall be processed in withthe fire extinguisher manufacturer’s instructions.
- Carbon Dioxide
The vapor phase of carbon dioxide shall be not lessthan 99.5 percent carbon dioxide. The water contentof the liquid phase shall be not more than 0.01 percentby weight [–30ºF (34.4ºC) dew point]. Oil contentof the carbon dioxide shall not exceed 10 ppm byweight.
- Water Types
When stored-pressure fire extinguishers are recharged,overfilling will result in improper discharge. The properamount of liquid agent shall be determined by using:
- one of the following:
- Exact measurement by weight;
- Exact measurement in volume;
- An anti-overfill tube, if provided; and
- A fill mark on fire extinguisher shell, if provided.
- Wet Chemical Agent Re-use
These agents are not to be re-used. If a wet chemicalextinguisher is partially discharged, all remaining wetchemical shall be discarded. Wet chemical agent shallbe discarded and replaced at the hydrostatic test interval.
- 4 Precautionary Pressurization Measures
- Pressure Gauges
Replacement pressure gauges shall have the properindicated charging (service) pressure, shall be markedfor use with the agent in the fire extinguisher, and shallbe compatible with the fire extinguisher valve bodymaterial.
- Stored-Pressure-Type Fire Extinguishers
A rechargeable stored-pressure-type fire extinguishershall be pressurized only to the charging pressurespecified on the fire extinguisher nameplate. Themanufacturer’s pressurizing adapter shall be connected to the valve assembly before the fire extinguisher is pressurized. A regulated source of pressure, set no higher than 25 psi (172 kPa) above the operating (service) pressure, shall be used to pressurize fire extinguishers. The gauge used to setthe regulated source of pressure shall be calibrated at least annually.
- An unregulated source of pressure such as a nitrogen cylinder without a pressure regulator, shall never be used because the fire extinguisher could be overpressurized and possibly rupture.
- A fire extinguisher shall never be left connected to the regulator of a high-pressure source for an extended period of time. A defective regulator could cause the container to rupture due to excess pressure.
- Pressurizing Gas
Only standard industrial-grade nitrogen with a dewpoint of –60ºF (–51ºC) or lower shall be used topressurize stored-pressure dry chemical andhalogenated-type fire extinguishers. Compressed airthrough moisture traps shall not be used forpressurizing even though so stated in the instructionson older fire extinguishers.
- Compressed air shall be permitted to be used from special compressor systems capable of delivering air with a dew point of –60ºF (–51.1ºC) or lower. The special compressor system shall be equipped with an automatic monitoring and alarm system to ensure that the dew point remains at or below –60ºF (–51.1ºC) at all times.
- Class D and halocarbon fire extinguishers shall be re-pressurized only with the type of expellant gas referred to on the fire extinguisher label.
- Recharge Record Keeping
Each fire extinguisher shall have a tag or label securelyattached that indicates the month and year rechargingwas performed and that identifies the personperforming the service. A ‘Verification of Service’(maintenance or recharging) collar shall also beattached to the extinguisher.
- Liquefied gas, halogenated agent, and carbon dioxide extinguishers that have been recharged without valve removal shall not be required to have a ‘Verification of Service’ collar installed following recharge.
- Cartridge and cylinder-operated extinguishers shall not be required to have a ‘Verification of Service’ collar installed.
- SPARE REFILLS
It is important that a minimum of 10 percent (of thenumber of various types of extinguishers on charge)replacement charges/refills should always be availablein stock so that discharged extinguisher can be rechargedand brought into use promptly.