Under OSHA’s portable fire extinguisher standard at 29 CFR 1910.157, how often fire extinguishers must be inspected per OSHA breaks into two recurring schedules: a visual inspection every month and a full maintenance check every twelve months. On top of those, certain extinguishers need an internal examination every six years and a hydrostatic pressure test every five or twelve years depending on the extinguishing agent and shell material. Miss any of these and the citation runs up to $16,550 per violation, per extinguisher.
Monthly Visual Inspections
Every portable extinguisher in the workplace has to be visually inspected once a month.1Occupational Safety and Health Administration. 1910.157 – Portable Fire Extinguishers The regulation says only that extinguishers “shall be visually inspected monthly” and leaves the checklist to industry practice. Most employers follow NFPA 10, which OSHA references directly for construction work and which shapes what inspectors look for everywhere else.
A competent person designated by the employer can do it. No outside contractor is required. The check confirms the extinguisher is in its assigned spot, the access path is clear, the pressure gauge sits in the operable range, the tamper seal and locking pin are intact, and there is no visible damage such as dents, corrosion, or leaking. Operating instructions should face outward and be legible. Two minutes per unit is typical.
OSHA does not explicitly require written records of monthly inspections. Keeping a dated tag or log is still worth the effort, because without a paper trail you are relying on verbal assurances during an OSHA visit.
Annual Maintenance Check
Every twelve months, each extinguisher gets a full maintenance check that goes well past the monthly walk-by.1Occupational Safety and Health Administration. 1910.157 – Portable Fire Extinguishers This is mandatory even if every monthly inspection came back clean, because the annual check examines internal mechanisms and the condition of the extinguishing agent — things you cannot evaluate from the outside.
NFPA 10 calls for a qualified technician, and most employers bring in a licensed fire protection service company. The job often requires breaking the tamper seal, inspecting mechanical components, and verifying that stored-pressure units are holding their charge. After service, a new verification tag showing the date of service goes on the unit. The employer must record the annual maintenance date and keep that record for one year after the last entry or the life of the shell, whichever is shorter.1Occupational Safety and Health Administration. 1910.157 – Portable Fire Extinguishers
One detail employers often miss: when an extinguisher is pulled from its location for annual service or recharging, you must provide alternate equivalent protection for that area until the unit is returned.2eCFR. 29 CFR Part 1910 Subpart L – Fire Protection A temporary replacement of equal or higher rating, a fire watch, or restricted access to the unprotected zone all work. Leaving a gap with no coverage is itself a citable violation.
Six-Year Internal Examination and Hydrostatic Testing
Stored-pressure dry chemical extinguishers on a 12-year hydrostatic cycle have to be emptied and given a full internal examination every six years.1Occupational Safety and Health Administration. 1910.157 – Portable Fire Extinguishers The exam catches problems like hardened or caked dry chemical that would keep the unit from discharging. Shake an old extinguisher and hear nothing move? That is the failure this exam prevents.
Hydrostatic testing pressurizes the cylinder with water to find leaks or structural weakness. The interval depends on what is inside and what the shell is made of:1Occupational Safety and Health Administration. 1910.157 – Portable Fire Extinguishers
- Every 5 years: carbon dioxide, stored-pressure water, cartridge-operated water, wetting agent, AFFF (aqueous film-forming foam), loaded stream, wet chemical, and dry chemical with stainless steel shells.
- Every 12 years: dry chemical with mild steel, brazed brass, or aluminum shells (stored-pressure or cartridge-operated), Halon 1211, Halon 1301, and dry powder with mild steel shells.
Only certified personnel with the right equipment can perform hydrostatic testing. The employer keeps a certification record showing the test date, the technician’s signature, and the extinguisher’s serial number. Those records stay on file until the unit is retested or permanently removed from service.1Occupational Safety and Health Administration. 1910.157 – Portable Fire Extinguishers An extinguisher that fails is condemned. It cannot be returned to service and must go through a hazardous waste facility or a fire equipment dealer set up to handle pressurized containers.
What OSHA Wants Documented
Recordkeeping is uneven across the schedule. Monthly inspections have no explicit written requirement, though a tag or log is standard practice. Annual maintenance dates must be recorded and retained for one year after the last entry or the shell’s service life, whichever is shorter. Hydrostatic test certifications must be kept until the next test or until the extinguisher is retired.1Occupational Safety and Health Administration. 1910.157 – Portable Fire Extinguishers
When These Rules Don’t Apply
Two boundaries are worth flagging. First, an employer with a written fire safety policy requiring immediate and total evacuation on alarm — paired with an emergency action plan under 29 CFR 1910.38 and a fire prevention plan under 29 CFR 1910.39 — is exempt from all of 1910.157, including the inspection schedule.3GovInfo. 29 CFR 1910.157 – Portable Fire Extinguishers The exemption only holds if there are no extinguishers actually present and no other OSHA standard requires them for the work. Building codes and insurers usually require extinguishers anyway.
Second, construction work is governed by a different standard, 29 CFR 1926.150, not 1910.157.4Occupational Safety and Health Administration. 29 CFR 1926.150 – Fire Protection It requires firefighting equipment to be “periodically inspected and maintained in operating condition” and points to NFPA 10A for maintenance procedures rather than spelling out monthly and annual intervals. Defective equipment must be replaced immediately. A 2A-rated extinguisher is required for every 3,000 square feet of protected building area at minimum.
Penalties for Missed Inspections
OSHA cites fire extinguisher violations with dollar amounts, not warnings. After the inflation adjustment effective January 15, 2025, the ceilings are:5Occupational Safety and Health Administration. OSHA Penalties
- Serious or other-than-serious violation: up to $16,550 per violation.
- Failure to abate: up to $16,550 per day past the abatement deadline.
- Willful or repeated violation: up to $165,514 per violation.
Each extinguisher can be its own violation. A warehouse with 20 uninspected units is not one citation; it can be 20. OSHA has assessed fines over $8,000 for a single extinguisher blocked by stored pallets. Violations corrected during the inspection sometimes avoid a monetary penalty, but the citation still lands on the employer’s record and counts toward the “repeated” multiplier next time around.