1910.1052(c)(1): Methylene Chloride 8-Hour Exposure Limit
Employers must make sure no employee is exposed to airborne methylene chloride (MC) above 25 parts per million (25 ppm) as an 8-hour time-weighted average.
Key takeaways
- 1910.1052(c)(1) is part of OSHA's general industry standards (29 CFR Part 1910).
- OSHA cited it 7 times in the last 3 years, in 7 inspections, with $45,197 in current penalties.
- 1 death is linked to inspections that cited this rule.
- Related part: 1910.1052(c) Permissible exposure limits (PELs) (20 citations).
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In this article
What this rule covers
29 CFR 1910.1052(c)(1) ("Eight-hour time-weighted average (TWA) PEL") is one requirement inside 1910.1052 Methylene chloride, an OSHA general industry standard (Part 1910). 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
(1) Eight-hour time-weighted average (TWA) PEL. The employer shall ensure that no employee is exposed to an airborne concentration of MC in excess of twenty-five parts of MC per million parts of air (25 ppm) as an 8-hour TWA. 7 citations
Source: eCFR, text current as of 2026-10-15. Read all of 1910.1052.
Export the list: 7 inspections cited 1910.1052(c)(1) in the last 3 years, with employer, location, penalty and date.
Purple Belt, $59/moInjuries linked to this rule
1 death is linked to inspections where OSHA cited 1910.1052(c)(1).
At 7:10 p.m. on October 29, 2024, an employee was scraping paint from a bathtub using a paint stripper containing 70-90% methylene chloride (Hoodstrip-888 Semi Paste Remover). The employee became unconscious due to inhaling methylene chloride vapors above the short-term exposure limit (STEL) and subsequently…
Where and how often it was cited
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OSHA interpretation letters
None exist. OSHA has not published a letter of interpretation for 1910.1052(c)(1).
Related parts of this rule
- 1910.1052(c) Permissible exposure limits (PELs) 20 citations
- 1910.1052(c)(2) Short-term exposure limit (STEL) 13 citations
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Frequently asked questions
What is the 8-hour limit for methylene chloride?
25 ppm as an 8-hour time-weighted average.
What does time-weighted average mean?
It is the average exposure over an 8-hour period.
Who must keep exposure under the limit?
The employer must ensure no employee is exposed in excess of the limit.
About this page
Sources
- 29 CFR 1910.1052 (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.