1910.94(a)(4)(i): Abrasive Blasting Exhaust Systems
Exhaust systems for abrasive blasting must be built, installed, inspected and maintained to ANSI Z9.2-1960 and ANSI Z33.1-1961. Dust leaks must be repaired as soon as possible, and static pressure drop must be checked after installation and periodically, with the system cleaned when a change shows partial blockage.
Key takeaways
- 1910.94(a)(4)(i) is part of OSHA's general industry standards (29 CFR Part 1910, Subpart G).
- OSHA cited it 14 times in the last 3 years, in 13 inspections, with $20,852 in current penalties.
- Most citations: TX (4), TN (2), OK (2).
- Related part: 1910.94(a) Abrasive blasting (65 citations).
- Free 5-minute toolbox talk for your crew below.
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In this article
What this rule covers
29 CFR 1910.94(a)(4)(i) is one requirement inside 1910.94 Ventilation, an OSHA general industry standard (Part 1910, Subpart G). 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
(i) The construction, installation, inspection, and maintenance of exhaust systems shall conform to the principles and requirements set forth in American National Standard Fundamentals Governing the Design and Operation of Local Exhaust Systems, Z9.2-1960, and ANSI Z33.1-1961, which is incorporated by reference as specified in § 1910.6. 14 citations
(a) When dust leaks are noted, repairs shall be made as soon as possible.
(b) The static pressure drop at the exhaust ducts leading from the equipment shall be checked when the installation is completed and periodically thereafter to assure continued satisfactory operation. Whenever an appreciable change in the pressure drop indicates a partial blockage, the system shall be cleaned and returned to normal operating condition.
Source: eCFR, text current as of 2026-10-15. Read all of 1910.94.
Export the list: 13 inspections cited 1910.94(a)(4)(i) in the last 3 years, with employer, location, penalty and date.
Purple Belt, $59/moWhere and how often it was cited
| Year | Citations |
|---|---|
| 2024 | 5 |
| 2025 | 7 |
| 2026 | 2 |
Top states: TX (4), TN (2), OK (2), AL (2), WI (1)
Largest penalties
| Employer | Location | Penalty for this rule |
|---|---|---|
| LASER SPECIALTIES INC. | TULSA, OK | $5,808 |
| TEWA LLC | VINTON, TX | $4,000 |
| PINTER MEMORIALS INC | BESSEMER, AL | $3,376 |
| HENOCK CONSTRUCTION, LLC | SAN ANTONIO, TX | $2,600 |
| IHOP | SAN ANTONIO, TX | $1,490 |
Free toolbox talk
A 5-minute crew talk on 1910.94(a)(4)(i), plus alerts when this rule changes. Free.
OSHA interpretation letters
None exist. OSHA has not published a letter of interpretation for 1910.94(a)(4)(i).
Related parts of this rule
- 1910.94(a) Abrasive blasting 65 citations
- 1910.94(a)(4) Exhaust ventilation systems 19 citations
- 1910.94(a)(5) Personal protective equipment 18 citations
- 1910.94(a)(3)(i) 15 citations
- 1910.94(a)(3) Blast-cleaning enclosures 15 citations
- 1910.94(a)(5)(ii) 4 citations
- 1910.94(a)(5)(i) 4 citations
- 1910.94(a)(2) Dust hazards from abrasive blasting 3 citations
- 1910.94(a)(1) Definitions applicable to this paragraph 1 citations
- 1910.94(a)(1)(ii) Abrasive-blasting respirator
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Frequently asked questions
What should be done about dust leaks?
Repairs shall be made as soon as possible.
When is static pressure drop checked?
When the installation is completed and periodically thereafter.
What if the pressure drop changes?
If an appreciable change shows a partial blockage, the system must be cleaned and returned to normal.
About this page
Sources
- 29 CFR 1910.94 (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 2026-11-06
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.