A fire extinguisher must be serviced once a year by law.

Portable fire extinguishers shall be inspected monthly, or at more frequent intervals, and serviced at least annually by a person licensed or registered by the State Fire Marshal as required by the Health and Safety Code, Division 12, Part 2, Chapter 1.5, Articles 2, 3, and 6.

NOTE: Inspection is a “quick check” that an extinguisher is available and will operate. It is intended to give reasonable assurance that the extinguisher is fully charged and operable. This is done by seeing that it is in its designated place, that it has not been actuated or tampered with, and that there is no obvious or physical damage or condition to prevent operation.

NOTE: Service as defined in the State Fire Marshal’s regulations pertains to the act of charging, recharging, inspecting, repairing, and hydrostatic testing of any portable fire extinguisher.

A fire extinguisher, rated not less than 2A, shall be provided for each 3,000 square feet of the floor area, or fraction thereof. Where the floor area is less than 3,000 square feet at least one extinguisher shall be provided. Travel distance from any point of the protected area to the nearest fire extinguisher shall not exceed 75 feet.

NFPA 10, Standard for Portable Fire Extinguishers.