1926.904: Storing Explosives and Blasting Agents
Explosives must be stored in approved facilities under ATF rules in 27 CFR part 55, and caps, detonating primers and primed cartridges may not share a magazine with other explosives. No smoking or open flames within 50 feet of magazines. Underground, permanent storage needs at least two exits, magazines must be at least 300 feet from shafts, adits or active work areas, and detonator magazines at least 50 feet from other explosive magazines.
Key takeaways
- 1926.904 is part of OSHA's construction standards (29 CFR Part 1926, Subpart U).
- Most-cited part: 1926.904(d).
- Free 5-minute toolbox talk for your crew below.
In this article
What this rule covers
29 CFR 1926.904, "Storage of explosives and blasting agents", is an OSHA construction standard (Part 1926, Subpart U). It has 6 numbered 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
Show the full text of 1926.904 (6 paragraphs)
(a) Explosives and related materials shall be stored in approved facilities required under the applicable provisions of the Bureau of Alcohol, Tobacco and Firearms regulations contained in 27 CFR part 55, Commerce in Explosives.
(b) Blasting caps, electric blasting caps, detonating primers, and primed cartridges shall not be stored in the same magazine with other explosives or blasting agents.
(c) Smoking and open flames shall not be permitted within 50 feet of explosives and detonator storage magazine.
(d) No explosives or blasting agents shall be permanently stored in any underground operation until the operation has been developed to the point where at least two modes of exit have been provided. Open (d)
(e) Permanent underground storage magazines shall be at least 300 feet from any shaft, adit, or active underground working area. Open (e)
(f) Permanent underground magazines containing detonators shall not be located closer than 50 feet to any magazine containing other explosives or blasting agents.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 58 FR 35311, June 30, 1993]
Source: eCFR, text current as of 2026-10-15.
Free toolbox talk
A 5-minute crew talk on 1926.904, plus alerts when this rule changes. Free.
OSHA interpretation letters
- Transportation of explosives over public or private roads. (1978-10-30)
- Interpretation on request for variance for storage of explosives and blasting agents. (1975-03-26)
Most-cited parts of this rule
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Frequently asked questions
How close can smoking or open flames be to an explosives magazine?
Not within 50 feet of explosives and detonator storage magazines.
Can blasting caps be stored with other explosives?
No. Blasting caps, electric blasting caps, detonating primers and primed cartridges may not be stored in the same magazine with other explosives or blasting agents.
How far must permanent underground magazines be from active work?
At least 300 feet from any shaft, adit or active underground working area.
About this page
Sources
- 29 CFR 1926.904 (eCFR), text current as of 2026-10-15
- U.S. Department of Labor enforcement data: OSHA inspections, citations and accident records, copied nightly
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.