Methylene Chloride (DCM)
Policy & information
In April 2024, the Environmental Protection Agency (EPA) issued a final rule regulating methylene chloride (CAS# 75-09-2, also identified as dichloromethane or DCM) under the Toxic Substances Control Act (TSCA). The EPA has determined this substance poses unreasonable risk to human health primarily due to neurotoxicity from short-term exposure to the chemical and liver effects and cancer from long-term exposure. This new regulation effectively prohibits most industrial and commercial uses of methylene chloride. The use of methylene chloride in laboratories will continue to be allowed under the EPA rule, however, with new and strict regulatory procedures.
To support our compliance, all current and future use or storage of any methylene chloride must be reviewed and approved by the UNCG EHS Department.
All laboratories are required to complete this Methylene Chloride Use Survey by May 31, 2026. Timely completion of this survey is essential for the EHS Department to work with affected labs to complete initial required compliance actions prior to the EPA deadline of November 9, 2026.
After completing the survey, laboratories with no plans for current or future use of methylene chloride will have fulfilled their compliance obligation. Those who store, use, or plan to use methylene chloride will be contacted by the EHS Department to coordinate further actions for compliance. Laboratories wishing to move away from methylene chloride use must dispose of current stocks through the Lab Waste Management process by November 9, 2026.
This Exposure Control Plan (ECP) covers safety practices to be followed for use of dichloromethane (methylene chloride, DCM) as a laboratory chemical at UNC Greensboro. Any deviation from this Plan requires approval in writing from the EHS Department. Users of DCM must be pre-approved by the Principal Investigator (PI) and/or Supervisor responsible for the laboratory in which it will be used. DO NOT USE DCM UNTIL YOU HAVE OBTAINED THE NECESSARY PRE-APPROVAL.
ELIMINATION
The preferred method to controlling exposure is to ELIMINATE the use of DCM from lab procedures.
SUBSTITUTION
If the use of DCM cannot be eliminated from lab procedures, the next best option is to substitute with an alternative chemical.
Penn State Fact Sheet: Solvent Alternatives
ENGINEERING CONTROLS
Local exhaust ventilation must be used for all processes employing DCM. Acceptable controls include fume hoods, glove boxes, exhausted enclosures, and snorkels. Work without ventilation controls may only proceed in cases where the EHS Department has approved the work in writing based on exposure monitoring results below the allowable limits.
ADMINISTRATIVE CONTROLS
All occupants of laboratories that use DCM shall review the Workplace Chemical Protection Program (WCPP) and this ECP prior to entry, sign that they have received the information they contain, and agree to abide by the training provided to them.
Storage of DCM must be compliant with requirements for Particularly Hazardous Substances.
Stop all use of DCM if any malfunction of the local exhaust ventilation device indicated above is suspected.
Any PPE suspected of coming in contact with DCM must be changed immediately.
Regulated areas will be established wherever exposures to DCM may exceed regulatory limits. These areas will be marked with signage that reads, in part:
Methylene Chloride Warning
Authorized Personnel Only
You may not enter these areas without first participating in specific training, and without supplied-air respiratory protection.
PERSONAL PROTECTIVE EQUIPMENT
DCM may only be handled while wearing a lab coat, safety glasses or splash goggles, and either polyvinyl alcohol gloves or double nitrile gloves. LLDPE laminate or butyl viton gloves may be used for procedures involving strong oxidizing acids. Polyvinyl alcohol or LLDPE laminate gloves may be used for procedures involving significant risk of fire. PIs, Instructors, and Supervisors are responsible for final glove selection.
EMERGENCY RESPONSE
In the event that DCM is spilled outside of a containment device, it is expected that airborne concentrations will exceed regulatory limits.
Notify others in the area of the spill. Evacuate the location where the spill occurred. Call UNCG Police at 336-334-4444. Report the spill to your Supervisor and to EHS at 336-334-4357. Remain on-site (outside the lab room) to provide detailed information to first responders.
CHANGE MANAGEMENT
EHS is responsible for reviewing this ECP annually, and for identifying any necessary updates to the exposure controls listed above. Each PI and/or Supervisor who oversees a work or lab area where DCM is used is responsible for ensuring all persons working under this ECP are properly implementing the exposure controls.