The federal rule underneath NFPA 10: what OSHA 1910.157 requires
Updated August 2026Reviewed August 2026
Almost every page written about extinguisher intervals answers with a standard number and no source. There is a better answer available, and it is a federal regulation you can open and read for yourself in about a minute.
Why a standard is not a law
NFPA 10 is a private consensus standard. It is written by a committee, published by a membership organisation, and it carries no legal force anywhere until a jurisdiction adopts it. Jurisdictions do adopt it, at different editions, years apart, with local amendments on top. So a page that answers "how often" with one number and the phrase "per NFPA 10" has told you almost nothing about the building in front of you.
The standards are also sold rather than published. NFPA offers free read-only access behind an account, under terms that do not permit copying tables out of it, so a page quoting an NFPA table at you is either licensed to do that or is not saying where the text came from. This site takes the third path: it cites the government regulations that state the intervals in their own words, and it names the adopted edition where a state has one on record.
What the federal regulation states, section by section
The Occupational Safety and Health Administration regulates portable fire extinguishers at 29 CFR 1910.157, and it states the intervals directly. Paragraph (e)(2) requires that portable extinguishers be visually inspected monthly. Paragraph (e)(3) requires the employer to see that they are subjected to an annual maintenance check. Paragraph (e)(4) requires that dry chemical extinguishers which need a 12-year hydrostatic test be emptied and put through the applicable maintenance procedures every 6 years.
Table L-1 of the same section sets the pressure-test interval by extinguisher type, and it is not one number: some types are on a 12-year cycle and others on a 5-year cycle. Paragraph (f)(16) sets what a test record must carry, which is the test date, the signature of the person performing the test, and the serial number or other identifier of the unit tested.
Those four paragraphs and that table are the citation. They are on the regulator's own site, they are free to read, and a customer who wants to know why you are there can be handed the section number.
Who the federal floor applies to
This is an employer duty. It reaches workplaces under OSHA jurisdiction wherever they are, with no state adoption required, which is why it is worth knowing even in a state that has adopted nothing recent. It is a floor rather than a ceiling: it sets what is owed at minimum, and it does not stop a state or a local authority asking for more.
What stacks on top of it
Above the federal floor sits your state's adopted edition of NFPA 10, and above that sits the authority having jurisdiction, which in practice is the fire marshal for the city or county the building is in. All three can be in play on one wall of extinguishers, and the local authority is the one who walks in the door.
The adopted editions on record run twelve years apart across the country, from a 2010 edition in one state to a 2022 edition in others. A page that names the edition your state adopted is doing something none of the general explainers do, and the adoption record for each jurisdiction is on its own page in the state licensing layer.
One state that writes its own interval
California does not leave the annual entirely to an adopted standard. Its own regulation at Cal. Code Regs. tit. 19, § 575.1 requires that extinguishers be maintained annually, or immediately after use, or when an inspection indicates it, or at the time of a hydrostatic test. The same section requires a new factory-charged extinguisher to be maintained within one year of its date of manufacture once it is sold.
That section also carries a rule that is a retirement date rather than a test date: a non-rechargeable extinguisher must be discharged and taken out of service at a maximum of twelve years from its date of manufacture, and must not be recharged or hydrostatically tested. Twelve years appears in both places and means two different things, which is exactly the sort of detail that gets flattened into a single wrong number elsewhere.
What this page deliberately does not tell you
It does not reproduce any NFPA table, because this research did not read one. It does not state agent-specific internal-examination intervals beyond the six-year rule the federal section carries: vendor summaries report additional annual and five-year internal examinations for certain agents, those reports were not confirmed against a readable primary source, and an unconfirmed interval is worse than no interval when someone is going to schedule work from it.
Confirm the intervals that apply to your assets against the edition your authority has adopted, and confirm that edition with the authority. Cadences vary by jurisdiction — verify with your AHJ.
Frequently Asked Questions
- Does OSHA require monthly fire extinguisher inspections?
- The federal regulation at 29 CFR 1910.157(e)(2) states that portable extinguishers shall be visually inspected monthly. It is an employer duty and it applies wherever OSHA jurisdiction reaches, without any state adoption of NFPA 10.
- Is NFPA 10 the law?
- Not by itself. It is a private consensus standard with no legal force until a jurisdiction adopts it, and jurisdictions adopt different editions with local amendments. The federal regulation is separate, and it applies on its own terms.
- Where can I read the federal intervals myself?
- They are published by the regulator at 29 CFR 1910.157. The monthly inspection is at (e)(2), the annual maintenance at (e)(3), the six-year internal maintenance at (e)(4), the pressure-test intervals in Table L-1, and the test record contents at (f)(16).
Cadences vary by jurisdiction — verify with your AHJ.
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