REGULATORY UPDATE

EPA's New Methylene Chloride Exposure Limits: What Employers Need to Know

The 2 ppm ECEL is far below OSHA's existing permissible exposure limit and creates new monitoring, control, and documentation obligations for covered uses.

Prepared: August 30, 2026

Suggested URL: /news/epa-methylene-chloride-ecel-limits

SEO description: EPA's methylene chloride rule establishes a 2 ppm eight-hour ECEL and a 16 ppm 15-minute limit. Learn the compliance dates and WCPP steps employers should take.

The U.S. Environmental Protection Agency's final risk management rule for methylene chloride creates a substantially more protective workplace exposure framework for uses that are allowed to continue under the Toxic Substances Control Act (TSCA). For covered operations, complying with OSHA's methylene chloride standard alone may no longer be sufficient.

What changed?

EPA finalized the methylene chloride rule in 2024. The rule prohibits most consumer uses and most industrial and commercial uses of methylene chloride, also known as dichloromethane or DCM. Certain uses may continue, including use as a laboratory chemical and several specified manufacturing and processing applications, but they are subject to a Workplace Chemical Protection Program (WCPP).

For workplaces covered by the WCPP, EPA established an Existing Chemical Exposure Limit (ECEL), an ECEL action level, and an EPA short-term exposure limit (EPA STEL). These limits are substantially lower than the corresponding OSHA limits.

Limit	8-hour TWA	15-minute TWA
EPA ECEL / EPA STEL	2 ppm	16 ppm
EPA ECEL action level	1 ppm	Not applicable
OSHA PEL / OSHA STEL	25 ppm	125 ppm
OSHA action level	12.5 ppm	Not applicable

TWA = time-weighted average; ECEL = Existing Chemical Exposure Limit; PEL = permissible exposure limit; STEL = short-term exposure limit.

The EPA ECEL of 2 ppm is 92% lower than OSHA's 25 ppm PEL. EPA's 16 ppm short-term limit is approximately 87% lower than OSHA's 125 ppm STEL. Covered employers must evaluate compliance against the EPA limits while continuing to meet applicable OSHA requirements.

Laboratories received extended compliance dates

In November 2025, EPA extended the WCPP compliance dates for non-federal laboratories using methylene chloride as a laboratory chemical. The extension aligned these laboratories with the schedule for federal laboratories and federal contractors. The current deadlines are:

•         November 9, 2026 - Complete initial exposure monitoring.

•         February 8, 2027 - Meet the 2 ppm ECEL and 16 ppm EPA STEL, establish regulated areas where required, and implement applicable respiratory and dermal protections.

•         May 10, 2027 - Implement required exposure controls and develop and implement the written exposure control plan.

For other existing owners and operators subject to the WCPP, the principal deadlines occurred in 2025. A covered operation that introduced methylene chloride after May 5, 2025 generally must complete initial monitoring within 30 days, comply with the exposure limits within four months, and implement required controls and an exposure control plan within seven months. Applicability and timing should be confirmed for the specific condition of use.

What does the Workplace Chemical Protection Program require?

The WCPP is more than a new numerical exposure limit. Covered owners and operators must build a documented program that addresses inhalation and dermal exposure. Core elements include:

•         Representative personal breathing-zone monitoring for the eight-hour ECEL and the highest likely 15-minute exposure periods.

•         Periodic monitoring based on results. Even when results are below the 1 ppm action level and at or below the EPA STEL, monitoring is generally required at least once every five years.

•         Additional monitoring following changes that may increase exposure, such as changes in process, production, control equipment, work practices, or releases.

•         Regulated areas and access restrictions where exposures exceed or may reasonably be expected to exceed the ECEL or EPA STEL.

•         Use of elimination, substitution, engineering controls, work practices, and administrative controls in the required sequence, with respiratory protection used when feasible controls do not fully reduce exposures to the limits.

•         A written exposure control plan documenting the controls considered, the rationale for selection, regulated areas, implementation actions, and procedures for changes that may increase exposure.

•         Chemically resistant gloves and activity-specific training where dermal contact is possible, together with other required skin and eye protections.

•         Written notification of monitoring results to potentially exposed persons within 15 working days, plus training, recordkeeping, and access to required records.

What should employers do now?

Organizations that use methylene chloride should not wait until the final compliance date to begin. A practical readiness process includes the following actions:

•         Confirm whether each use is prohibited, exempt, or allowed to continue under a WCPP.

•         Inventory methylene chloride-containing products and document quantities, concentrations, locations, tasks, frequencies, and potentially exposed personnel.

•         Review existing exposure data to determine whether it meets EPA's representativeness, age, and analytical performance requirements.

•         Develop a sampling plan that captures both full-shift exposure and the highest-exposure 15-minute tasks under representative worst-case conditions.

•         Evaluate fume hoods, local exhaust, enclosed processes, transfer methods, waste handling, spill response, and work practices against the new limits.

•         Verify glove compatibility and change-out practices, and evaluate whether a compliant respiratory protection program may be needed during implementation or for specific tasks.

•         Prepare the written exposure control plan, regulated-area procedures, training materials, notifications, and recordkeeping system before the applicable deadlines.

How OSI can help

OSI can help organizations determine how EPA's methylene chloride rule applies to their operations and develop a practical path to compliance. Our industrial hygiene and EHS professionals can support chemical-use reviews, task-based exposure assessments, eight-hour and 15-minute personal air monitoring, ventilation and work-practice evaluations, control recommendations, PPE assessments, written WCPP exposure control plans, employee training, and ongoing compliance monitoring.

If your laboratory or facility uses methylene chloride, now is the time to confirm applicability and establish a monitoring and compliance strategy. Contact OSI to discuss an assessment tailored to your operations.

Sources

1. U.S. EPA, Risk Management for Methylene Chloride: View source

2. 40 CFR 751.109, Workplace Chemical Protection Program: View source

3. U.S. EPA, EPA Extends Compliance Deadlines for Methylene Chloride Rule: View source

4. OSHA, 29 CFR 1910.1052 - Methylene Chloride: View source

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