In April 2024, the Environmental Protection Agency (EPA) issued a final rule regulating methylene chloride (also called dichloromethane or DCM) under the Toxic Substances Control Act (TSCA).

The EPA methylene chloride rule bans manufacturing for all consumer uses and bans most industrial and commercial uses. This rule potentially impacts the University of Houston (UH) community, particularly those who use methylene chloride as a laboratory solvent/reagent, and persons using certain products containing methylene chloride such as paint strippers, adhesives, sealants, and degreasers/cleaners.

While laboratory use of DCM is not banned, the EPA has issued strict requirements for any continued use (FAQ for DCM Ban) . These include:

• Documentation of attempts to eliminate or substitute methylene chloride
• Documentation of all control measures, including those not implemented
• Initial and periodic exposure monitoring for anyone potentially exposed, including recordkeeping and dissemination of monitoring data
• Development and implementation of a Workplace Chemical Protection Program
• Recordkeeping to maintain auditable documentation of these measures

Implementation of these requirements is mandated to the following timeline:

• May 5, 2025: Complete initial exposure monitoring for existing chemical exposure limit (ECEL) and short-term exposure limit (STEL)
• August 1, 2025 or three months after monitoring: Implement controls
• October 30, 2025: Develop and implement an Exposure Control Plan

Based on the above compliance timelines, EHS personnel will work with our Research/Teaching PIs and Shop managers to determine where and how methylene chloride is used on campus, which uses can continue and which must stop, and develop the initial exposure monitoring plan. An intake form will  be to UH Research/Teaching PIs and Shop managers to facilitate gathering of accurate data on storage and use of methylene chloride or products containing methylene chloride on the campus.