1910.430(b): Diving Air Compressor Systems
Compressors supplying air to divers must have a volume tank with an inlet check valve, a pressure gauge, a relief valve and a drain valve, with intakes away from exhaust and contaminants. Diver air must not contain carbon monoxide greater than 20 p/m, carbon dioxide greater than 1,000 p/m, oil mist greater than 5 milligrams per cubic meter, or a noxious or pronounced odor, and output must be tested for purity every 6 months.
Key takeaways
- 1910.430(b) is part of OSHA's general industry standards (29 CFR Part 1910, Subpart T).
- OSHA cited it 4 times in the last 3 years, in 3 inspections, with $24,616 in current penalties.
- 1 death is linked to inspections that cited this rule.
- Related part: 1910.430(b)(4) (3 citations).
- Free 5-minute toolbox talk for your crew below.
In this article
What this rule covers
29 CFR 1910.430(b) ("Air compressor system") is one requirement inside 1910.430 Equipment, an OSHA general industry standard (Part 1910, Subpart T). It includes 8 sub-paragraphs. The official text below is copied word for word from the Electronic Code of Federal Regulations (eCFR). The numbers, injury cases and training on this page show how OSHA enforces it on real job sites.
Official text
(b) Air compressor system. 4 citations
(1) Compressors used to supply air to the diver shall be equipped with a volume tank with a check valve on the inlet side, a pressure gauge, a relief valve, and a drain valve.
(2) Air compressor intakes shall be located away from areas containing exhaust or other contaminants. 1 citations
(3) Respirable air supplied to a diver shall not contain:
(i) A level of carbon monoxide (CO) greater than 20 p/m;
(ii) A level of carbon dioxide (CO2) greater than 1,000 p/m;
(iii) A level of oil mist greater than 5 milligrams per cubic meter; or
(iv) A noxious or pronounced odor.
(4) The output of air compressor systems shall be tested for air purity every 6 months by means of samples taken at the connection to the distribution system, except that non-oil lubricated compressors need not be tested for oil mist. Open (b)(4) 3 citations
Source: eCFR, text current as of 2026-10-15. Read all of 1910.430.
Injuries linked to this rule
1 death is linked to inspections where OSHA cited 1910.430(b).
At 2:00 p.m. on June 25, 2024, an employee working as a commercial diver for a highway and bridge contractor had descended 19 feet to the ocean floor. The employee was acclimating himself for a commercial diving operation. The employeewas a new diver to the…
Where and how often it was cited
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OSHA interpretation letters
Related parts of this rule
- 1910.430(b)(4) 3 citations
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Frequently asked questions
How often must diver air be tested for purity?
Every 6 months, using samples taken at the connection to the distribution system.
What is the carbon monoxide limit for diver air?
Air supplied to a diver shall not contain a level of carbon monoxide greater than 20 p/m.
Do non-oil lubricated compressors need oil mist testing?
No. Non-oil lubricated compressors need not be tested for oil mist.
About this page
Sources
- 29 CFR 1910.430 (eCFR), text current as of 2026-10-15
- U.S. Department of Labor enforcement data: OSHA inspections, citations and accident records, copied nightly; data as of 2026-10-20
3-year window. Federal OSHA only; state-plan rules are not counted. Plain-language text is a summary, not legal advice; the official text controls. Black Belt Safety is not part of OSHA or the Department of Labor.