Portable fire extinguisher rules

The portable fire extinguisher rules in 1910.157 apply whenever extinguishers are provided for employee use, covering their placement, use, maintenance, and testing.

• Scope and application in 1910.157(a) explains that paragraph (d) (distribution and selection) does not apply to extinguishers provided for employee use on the outside of workplace buildings or structures.

• If extinguishers are present but not intended for employee use and the employer has an emergency action plan and a fire prevention plan that meet 1910.38 and 1910.39, then only the inspection/maintenance and hydrostatic testing requirements in paragraphs (e) and (f) apply, per 1910.157(a).

• Practical tip: confirm whether extinguishers are intended for employee use and maintain the required EAP and fire prevention plan if you plan to limit extinguisher-related obligations.

An employer is exempt from all requirements of 1910.157 if they have a written fire safety policy requiring the immediate and total evacuation of employees when the fire alarm sounds, that policy includes an emergency action plan and a fire prevention plan that meet 1910.38 and 1910.39 and [https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.39], and no extinguishers are provided in the workplace.

• See the exemption language at 1910.157(b)(1).
• Note: You are not exempt if another specific OSHA standard in part 1910 requires a portable fire extinguisher.

If an employer’s emergency action plan (meeting 1910.38) designates certain employees as the only ones authorized to use available portable fire extinguishers and requires all other employees to evacuate, the employer is exempt from the extinguisher distribution requirements in paragraph (d).

• See the specific provision at 1910.157(b)(2).
• Practical point: you must document the designated-user policy in the emergency action plan and train the designated employees appropriately.

Portable extinguishers must be mounted, located, and identified so they are readily accessible to employees without exposing them to possible injury.

• See the plain requirement at 1910.157(c)(1).

• Practical guidance: place extinguishers where employees can get to them quickly along normal travel paths, post clear signage if visibility is limited, and avoid locations that require workers to pass through hazards to reach the extinguisher.

You must use only portable extinguishers that are approved by a recognized testing agency; uncertified or homemade extinguishers are not acceptable.

• The standard language is in 1910.157(c)(2).

• Practical step: choose extinguishers with a label from a nationally recognized testing laboratory (e.g., UL) and keep documentation of the approvals when procuring equipment.

Employers must not provide or make available portable fire extinguishers that use carbon tetrachloride or chlorobromomethane as the extinguishing agent.

• This prohibition is stated in 1910.157(c)(3).

• Safety note: both agents are hazardous to health and long banned for portable extinguishers; remove any such units from service immediately.

Portable fire extinguishers must be kept fully charged, operable, and returned to their designated places at all times except during use.

• See the maintenance requirement at 1910.157(c)(4).

• Practical checklist: ensure monthly inspections, immediate replacement of missing or discharged units, and visible tags showing last inspection date.

Yes — employers must remove from service all soldered or riveted shell self-generating soda acid or self-generating foam extinguishers and any gas cartridge water-type extinguishers that operate by inverting to rupture a cartridge or start an uncontrollable reaction.

• The removal requirement is in 1910.157(c)(5).

• Practical note: these older designs are unsafe and obsolete; inspect inventory and dispose of these models per manufacturer and local disposal rules.

Employers must select and distribute portable extinguishers based on the classes of fires anticipated in the workplace and on the size and degree of hazard that would affect extinguisher use.

• See the selection requirement at 1910.157(d)(1).

• Practical steps: perform a hazard assessment (identify likely fire classes A, B, C, D), choose appropriately rated extinguisher types and sizes, and place them where employees can reach and effectively use them for the anticipated fire size.

For Class A fires, employers must distribute extinguishers so that an employee’s travel distance to any extinguisher is 75 feet (22.9 m) or less.

• This distribution requirement is in 1910.157(d)(2).

• Practical tip: measure along normal walking routes (not “as the crow flies”) and place extinguishers at intervals that keep travel distances within the 75-foot limit.

For Class B fires, the employer must distribute portable fire extinguishers so that the travel distance from the Class B hazard area to any extinguisher is 50 feet (15.2 m) or less.

• See the requirement at 1910.157(d)(4).

• Practical example: in areas with flammable liquids or gases, place extinguishers closer to the hazard to meet the 50-foot requirement.

Extinguishers for Class C hazards should be distributed based on the appropriate pattern for the existing Class A or Class B hazards at that location.

• The standard states this at 1910.157(d)(5).

• Practical guidance: if the same area contains Class A or B risks, follow their travel-distance placement rules and choose extinguishers rated for both the electrical and the underlying fire class.

Class D extinguishing agents must be provided in combustible metal working areas where metal powders, flakes, shavings, or similarly sized products are generated at least once every two weeks, and they must be distributed so the travel distance to an extinguisher is 75 feet (22.9 m) or less.

• See 1910.157(d)(6).

• Practical action: in metalworking areas with frequent generation of combustible metal debris, keep a Class D agent nearby and inspect that the agent matches the specific metal(s) present.

Yes — employers may use uniformly spaced standpipe systems or hose stations connected to a sprinkler system instead of Class A portable extinguishers if those systems meet the requirements of 1910.158 or 1910.159, provide total coverage of the area, and employees receive at least annual training in their use.

• See the substitution provision at 1910.157(d)(3).

• Practical reminder: if you substitute hose systems, ensure the systems meet those other standards and schedule the required annual employee training.

The employer is responsible for inspection, maintenance, and testing of all portable extinguishers, and visual inspections must be performed monthly.

• See the employer responsibility at 1910.157(e)(1) and the monthly inspection requirement at 1910.157(e)(2).

• Quick checklist: monthly inspections should check pressure gauges, seals, signs of damage or corrosion, and that extinguishers are in their designated locations.

Employers must have portable fire extinguishers undergo an annual maintenance check, and they 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 less.

• The annual maintenance and retention rule is in 1910.157(e)(3).

• Practical note: stored-pressure extinguishers generally do not require internal examination at the annual check; keep maintenance stickers or logs accessible for OSHA upon request.

Stored-pressure dry chemical extinguishers that require a 12-year hydrostatic test must be emptied and subjected to applicable maintenance procedures every 6 years, but dry chemical extinguishers with non-refillable disposable containers are exempt from the 6-year empty-and-maintain requirement. When recharging or hydrostatic testing is performed, the 6-year interval restarts from that date.

• See the full provision at 1910.157(e)(4).

• Practical action: track each extinguisher’s service and recharge dates so you can schedule the 6-year maintenance and the 12-year hydrostatic test when required.

When portable fire extinguishers are removed from service for maintenance or recharging, employers must provide alternate equivalent protection in the meantime.

• The requirement is stated in 1910.157(e)(5).

• Practical examples of alternate protection: temporarily station a serviced replacement extinguisher of equal rating nearby, or ensure hose/standpipe coverage is available while the unit is out of service.

Extinguishers must be hydrostatically tested at the intervals listed in Table L-1 unless one of the conditions in 1910.157(f)(2)(i)-(v) applies (for example, the unit has been repaired by welding or shows thread damage, pitting corrosion, has been burned, or a calcium chloride agent was used in a stainless steel shell).

• See the test intervals in Table L-1 of 1910.157(f) and the exception list in 1910.157(f)(2).

• Practical step: consult Table L-1 for the correct interval for each extinguisher type and perform additional testing whenever the unit shows new corrosion or mechanical injury as required by 1910.157(f)(4).

Yes — in addition to an external visual examination, an internal examination of cylinders and shells to be tested must be made prior to the hydrostatic test.

• See 1910.157(f)(3).

• Practical note: ensure qualified personnel open and inspect the shell interior for corrosion, pitting, or other defects before hydrostatic testing.

Hose assemblies that have a shut-off nozzle at the discharge end must be hydrostatically tested at the same interval as the extinguisher on which the hose is installed, with carbon dioxide hose assemblies tested at 1,250 psi and dry chemical/dry powder hose assemblies tested at 300 psi; carbon dioxide hose tests must be done inside a protective cage, and hose assemblies that pass do not require stamping or recording.

• See the hose assembly rules at 1910.157(f)(5), 1910.157(f)(6), 1910.157(f)(7), 1910.157(f)(8), and 1910.157(f)(9).

• Practical reminder: coordinate hose testing with extinguisher testing schedules and ensure CO2 hose tests are performed in the required protective enclosure.

Carbon dioxide extinguishers and nitrogen or carbon dioxide cylinders used with wheeled extinguishers must be tested every 5 years at 5/3 of the service pressure stamped on the cylinder; nitrogen cylinders that meet 49 CFR 173.34(e)(15) may be hydrostatically tested every 10 years.

• See 1910.157(f)(10) for the 5-year/5/3 pressure requirement and the reference to 49 CFR 173.34(e)(15) for the 10-year option.

• Practical step: identify the service pressure stamped on each cylinder and schedule testing at the correct pressure and interval; keep certificates of the test.

Any extinguisher shell, cylinder, or cartridge that fails a hydrostatic pressure test or is not fit for testing must be removed from service and removed from the workplace.

• The removal requirement is in 1910.157(f)(14).

• Practical action: tag and segregate failed units so they cannot be returned to service and document disposal or scrap procedures.

Employers must keep certification records showing the date of the hydrostatic test, the signature of the person who performed the test, and the serial number or other identifier of the tested extinguisher; these records must be kept until the extinguisher is hydrostatically retested at the interval in Table L-1 or until the extinguisher is taken out of service, whichever comes first.

• See the recordkeeping requirement at 1910.157(f)(16).

• Practical suggestion: maintain a searchable log (electronic or paper) with test certificates linked to each extinguisher ID to make retrieval easy for inspectors.

Employers who provide portable extinguishers for employee use must provide an educational program to familiarize employees with general extinguisher principles and the hazards of incipient firefighting upon initial employment and at least annually; employees designated to use firefighting equipment under an emergency action plan must receive training in the use of that equipment.

• See the training and education rules at 1910.157(g)(1), 1910.157(g)(2), and 1910.157(g)(3).

• Practical elements: include hands-on demonstrations, extinguisher selection and limitations (class ratings), safe approach distance, and when to evacuate rather than fight a fire.