Six Year Maintenance Fire Extinguisher Testing
NFPA 10 7.3 requires that every 6 years, stored pressure fire extinguishers that require a 12-year hydrostatic test (e.g. dry chemical extinguishers) must be emptied and proper maintenance procedures performed.
This should be done professionally, and must be fully emptied and subjected to a full internal inspection for corrosion and applicable maintenance procedures, including a thorough examination of all mechanical parts, extinguishing agent and expellant.
When these maintenance procedures are performed during periodic recharging or hydrostatic testing, the six year requirement shall begin from that date. The exception to this rule is non-rechargeable extinguishers, which are required to be removed from service 12 years from the date of manufacture.
Extinguishers that pass the six year maintenance are then recharged, reassembled, and receive a six year service label and a verification of service collar.
Hydrostatic Fire Extinguisher Testing
At certain intervals, fire extinguishers are required to be pressure tested using water or some other noncompressible fluid to verify its strength against unwanted rupture performed by a facility that is approved by the D.O.T. to requalify cylinders. This is called hydrostatic testing and includes both an internal and external examination of the cylinder.
Hydrostatic testing intervals for fire extinguishers are outlined in NFPA 10. Test intervals for some of the most commonly found extinguishers are as follows:
• Pressurized water, carbon dioxide and wet chemical extinguishers – every 5 years
• Dry chemical extinguishers – every 12 years
Because this testing requires special training and equipment, it needs to be performed by an approved extinguisher servicing company.