If you run operations where workers strip paint, degrease metal parts, or handle adhesives containing methylene chloride, here's the trap I see catch even careful employers: there are two federal agencies regulating the same chemical, under two different exposure limits, on two different timelines, and satisfying one does not mean you've satisfied the other. OSHA just reopened its rulemaking docket on methylene chloride for a second round of public comment. That's worth understanding on its own terms. But the real lesson sitting underneath this news is that methylene chloride compliance now runs on parallel tracks, and a lot of safety programs are still built for only one of them.
On July 22, 2026, OSHA published a notice in the Federal Register reopening the comment record on its proposed revision to the methylene chloride standard, docket OSHA-2025-0012. Written comments are due on or before August 21, 2026. The agency reopened the record after its Advisory Committee on Construction Safety and Health (ACCSH) reviewed the rulemaking, which is standard practice whenever a proposed change touches the construction sector's version of a standard. Nothing about the underlying exposure limits has changed yet. What's changed is that stakeholders, especially in construction, get one more chance to weigh in before OSHA moves toward a final rule.
What OSHA Announced, and What It Didn't
Let's be precise about what this notice actually does, because "OSHA reopens methylene chloride rulemaking" sounds bigger than it is. This is a procedural step in an ongoing rulemaking, not a new regulation and not an enforcement action. The docket traces back to July 1, 2025, when OSHA first published a proposal to revise 29 CFR 1910.1052. That comment period was originally set to close September 2, 2025, then extended 60 days to November 1, 2025 after stakeholders asked for more time. ACCSH then took up the rulemaking, and its review is what triggered this second, 30-day reopening.
The substance of OSHA's proposal is narrower than most people assume when they hear "methylene chloride rule change." OSHA is not proposing to lower the permissible exposure limit. The stated goals are to reduce compliance burdens, allow additional types of respirators where the current standard is more restrictive than necessary, and better align the respiratory protection provisions of 1910.1052 with OSHA's general Respiratory Protection standard at 29 CFR 1910.134. In plain terms: OSHA is trying to make the paperwork and PPE selection logic more consistent across standards, not tighten the exposure ceiling.
That distinction matters for how you should be spending your attention right now. If your compliance concern is "is OSHA about to make my exposure limit stricter," the answer, based on what's actually in this docket, is no. If your concern is "will my respiratory protection program need to change," that's the live question, and it's exactly the kind of thing worth commenting on before August 21 if your operation would be affected by how the final language handles respirator selection and program alignment.
The Standard You're Actually Living Under Today
Nothing in this reopening changes your obligations under the current standard, which has been in force since 1997 and applies through three parallel provisions: general industry at 29 CFR 1910.1052, shipyard employment at 29 CFR 1915.1052, and construction at 29 CFR 1926.1152. The permissible exposure limit for methylene chloride, 25 parts per million as an 8-hour time-weighted average, has not moved since OSHA finalized it in 1997, and this rulemaking does not propose to move it. The standard also sets a short-term exposure limit of 125 ppm averaged over any 15-minute period, and an action level of 12.5 ppm, half the PEL, which is the trigger for periodic exposure monitoring and, depending on results, medical surveillance under paragraphs (d) and (j) of the standard.
Those numbers are the ones that still govern your regulated areas, your exposure monitoring schedule, your hazard communication labeling, and your medical surveillance triggers today. I have seen employers read headlines about a "methylene chloride rule change" and quietly assume their existing program is grandfathered or under review, so nothing needs to happen. That's backwards. Until a final rule publishes and its effective date arrives, the 1997 numbers are the enforceable ones, full stop.
Why the Construction Advisory Committee Got Involved
ACCSH exists specifically to review OSHA rulemakings that affect construction employers before those rules finalize, because construction work often involves transient job sites, subcontractor chains, and exposure patterns that don't map cleanly onto a general-industry facility. Paint and coating removal, surface prep, and adhesive work involving methylene chloride are common in construction and renovation settings, so a rule change to respirator selection or program alignment has real, site-specific consequences for that sector. ACCSH's review is why this docket reopened at all. If your operation is a construction or renovation contractor rather than a fixed general-industry facility, this is the version of the comment period that was built with your operations specifically in mind, and it is worth reading the docket rather than assuming it's a general-industry matter that doesn't touch you.
The Overlap Nobody's Compliance Calendar Accounts For
Here is the part of this story that I think deserves more attention than the comment-period news itself. OSHA is not the only federal agency with a live exposure limit for methylene chloride, and the other one is considerably stricter.
In April 2024, EPA finalized a risk management rule for methylene chloride under Section 6 of the Toxic Substances Control Act, effective July 8, 2024. That rule found unreasonable risk to workers and the public and banned manufacturing, processing, and distribution of methylene chloride for all consumer uses and most industrial and commercial uses, on a phased schedule. For the uses EPA still allows, generally described as critical uses such as laboratory analysis, certain adhesives and sealants, and specific industrial processing roles, continued use is conditioned on a Workplace Chemical Protection Program, or WCPP. And the WCPP's exposure limit is not the OSHA number.
| Requirement | OSHA General Industry Standard (29 CFR 1910.1052) | EPA TSCA Workplace Chemical Protection Program |
|---|---|---|
| Legal authority | Occupational Safety and Health Act | Toxic Substances Control Act, Section 6 |
| 8-hour TWA exposure limit | 25 ppm | 2 ppm (Existing Chemical Exposure Limit) |
| Short-term exposure limit (15 min) | 125 ppm | 16 ppm |
| Action level | 12.5 ppm | 1 ppm |
| Governs | All covered general industry, shipyard, and construction employers | Only the surviving "critical use" categories EPA still permits |
| Status as of August 2026 | Unchanged since 1997; procedural amendments open for comment through Aug. 21, 2026 | Prohibitions and WCPP dates phased in through 2026–2029, several extended by EPA |
EPA's exposure ceiling for methylene chloride is twelve and a half times lower than OSHA's. An operation that is fully compliant with OSHA's 25 ppm PEL can still be in violation of EPA's 2 ppm limit if any part of its methylene chloride use falls into one of the surviving critical-use categories. I have come to think this gap is the single most under-recognized compliance risk in this space right now, because most safety programs were built around one regulator's number, and the assumption that "OSHA compliant" equals "compliant" quietly stops being true the moment EPA's rule applies to your specific use.
EPA has also been actively adjusting its own compliance dates. The prohibition on industrial and commercial use generally takes effect April 28, 2026, with certain critical-use exceptions extending to May 8, 2029. WCPP compliance dates for initial monitoring, establishing regulated areas, and implementing exposure control plans have each been extended at least once, most recently pushed into 2026 and 2027 to give laboratories and other affected facilities more time. If your operation touches any surviving use category, you need both calendars, not one.
What to Do Before August 21, 2026
A few concrete steps, in order of what actually protects you:
- Don't wait on OSHA's rulemaking to update anything you're required to do today. The 25 ppm PEL, 125 ppm STEL, and 12.5 ppm action level are live and enforceable right now, regardless of where this rulemaking ends up.
- Figure out whether any of your methylene chloride use falls under an EPA critical-use category. If it does, you're building toward the 2 ppm ECEL and the full WCPP, not the OSHA PEL, and the compliance dates for monitoring and regulated areas are closer than the OSHA rulemaking timeline.
- Read the actual docket before commenting or assuming impact. OSHA-2025-0012 is available through Regulations.gov and the Federal Register notice at 2026-14854. If your respirator program relies on features the current 1910.1052 language restricts, this is the window to say so.
- If you're a construction or renovation employer, treat the ACCSH involvement as a signal, not a formality. The committee reviewed this rulemaking because construction exposure patterns are different from fixed-facility patterns, and the comment window closing August 21 is your chance to flag anything that doesn't work on a job site.
- Audit your respiratory protection program against 1910.134 now, independent of the rulemaking. OSHA's stated intent is alignment; a program that's already consistent with the general respiratory protection standard will have less to redo whenever a final rule does publish.
Effective Dates and Deadlines at a Glance
- July 1, 2025 — OSHA publishes initial proposal to revise 29 CFR 1910.1052.
- November 1, 2025 — First extended comment period closes (extended from the original September 2, 2025 deadline).
- July 22, 2026 — Federal Register notice reopens the record following ACCSH review (Document 2026-14854).
- August 21, 2026 — Deadline for the current 30-day reopened comment period.
- April 28, 2026 — EPA's general prohibition on industrial and commercial use of methylene chloride takes effect, separate from OSHA's rulemaking.
- May 8, 2029 — Extended deadline for specific EPA critical-use exceptions.
FAQ
Is OSHA lowering the permissible exposure limit for methylene chloride? No. The current proposal focuses on respiratory protection flexibility and aligning 1910.1052 with the general Respiratory Protection standard, 29 CFR 1910.134. The 25 ppm 8-hour TWA, 125 ppm STEL, and 12.5 ppm action level are not proposed to change.
Do I need to submit a comment by August 21, 2026? Only if you want to influence the final rule. Submitting a comment is voluntary, but it's the only formal mechanism for flagging operational concerns, such as respirator selection issues on construction sites, before OSHA finalizes changes.
Does this OSHA rulemaking affect EPA's methylene chloride restrictions? No, they're separate legal authorities. OSHA regulates workplace exposure under the OSH Act; EPA regulates manufacturing, processing, and use under the Toxic Substances Control Act. A facility can be fully compliant with one and out of compliance with the other.
What is the actual current exposure limit I need to comply with today? Under OSHA's 1997 standard, still in force: 25 ppm as an 8-hour time-weighted average, 125 ppm as a 15-minute short-term limit, and a 12.5 ppm action level triggering monitoring obligations. If your use falls under EPA's Workplace Chemical Protection Program, the applicable limit is 2 ppm TWA and 16 ppm STEL instead.
Where can I read the actual rulemaking docket? The Federal Register notice is published as Document 2026-14854, docket number OSHA-2025-0012, available through the Federal Register and Regulations.gov.
Methylene chloride compliance work like this, sorting out which agency's number actually governs a given use, is a good example of why I recommend clients build a single exposure-control plan that satisfies the stricter of any two overlapping limits rather than maintaining separate OSHA and EPA programs. If you want a second set of eyes on where your operation actually sits on both tracks, that's a conversation worth having before either deadline, not after. You can find more on how we approach overlapping regulatory obligations at certify.consulting, including our guidance on building a unified industrial hygiene compliance program that covers OSHA, EPA, and state-level requirements at once.
Last updated: 2026-08-01
Jared Clark
Principal Consultant, Certify Consulting
Jared Clark is the founder of Certify Consulting, helping organizations achieve and maintain compliance with international standards and regulatory requirements.