Respirator selection
Methylene chloride (Dichloromethane) respirator selectionCH2Cl2
Paint stripper/remover, metal degreaser, solvent, aerosol propellant, foam blowing, extraction. Coatings, pharma, manufacturing.
These are federal OSHA limits. The PEL shown is the federal OSHA value. About two dozen states run their own OSHA-approved plans, and some — notably California (Cal/OSHA) — enforce lower or additional exposure limits. If you work under a state plan, check your state's PEL and enter it as a custom limit in the calculator.
Cartridge (limited use): Organic Vapor (OV) — escape canister only — Black band
An APR fitted with the correct cartridge is only adequate up to its MUC (below) — the cartridge must be able to capture methylene chloride (dichloromethane). CORRECTED after verifying NIOSH npgd0414: DCM is a potential occupational carcinogen (Ca) and the Pocket Guide lists an air-purifying full-facepiece OV gas-mask canister for ESCAPE ONLY (APF 50) — the same escape-only provision as benzene/perc, not 'no APR at all'. For routine work exposure NIOSH lists SCBA and supplied-air-with-auxiliary-SCBA only. OSHA substance standard 29 CFR 1910.1052 governs and effectively bars air-purifying respirators for routine use: DCM is poorly adsorbed by carbon, has poor warning properties, and is metabolized to carbon monoxide. Do NOT use an OV cartridge/canister for routine protection — supplied air / SCBA required for work. You must establish a change-out schedule; never rely on taste or smell. See the cartridge & filter guide.
Calculator for Methylene chloride (Dichloromethane)
Result
Enter a concentration and an exposure limit to see the
compliant respirators and their Maximum Use Concentration.
Hazard ratio = concentration ÷ OEL · Minimum APF must meet or exceed it · MUC = APF × OEL (capped at IDLH). Source: OSHA 29 CFR 1910.134(d)(3)(i)(A), Table 1 — Assigned Protection Factors. Last verified 2026-07-16.
Maximum use concentration for Methylene chloride (Dichloromethane) by respirator
MUC = APF × the OSHA PEL (25 ppm), capped at the IDLH (2,300 ppm). Use this as a reference for the highest concentration each respirator class may be used at.
| Respirator | APF | MUC (ppm) |
|---|---|---|
| Air-Purifying Respirator · Quarter mask | 5 | 125 |
| Air-Purifying Respirator · Half mask | 10 | 250 |
| Supplied-Air Respirator (Airline) · Half mask · Demand | 10 | 250 |
| Self-Contained Breathing Apparatus · Half mask · Demand | 10 | 250 |
| Powered Air-Purifying Respirator · Helmet / hood | 25 | 625 |
| Powered Air-Purifying Respirator · Loose-fitting facepiece | 25 | 625 |
| Supplied-Air Respirator (Airline) · Helmet / hood · Continuous flow | 25 | 625 |
| Supplied-Air Respirator (Airline) · Loose-fitting facepiece · Continuous flow | 25 | 625 |
| Air-Purifying Respirator · Full facepiece | 50 | 1,250 |
| Powered Air-Purifying Respirator · Half mask | 50 | 1,250 |
| Supplied-Air Respirator (Airline) · Full facepiece · Demand | 50 | 1,250 |
| Supplied-Air Respirator (Airline) · Half mask · Continuous flow | 50 | 1,250 |
| Supplied-Air Respirator (Airline) · Half mask · Pressure-demand / positive-pressure | 50 | 1,250 |
| Self-Contained Breathing Apparatus · Full facepiece · Demand | 50 | 1,250 |
| Powered Air-Purifying Respirator · Full facepiece | 1,000 | 2,300IDLH |
| Supplied-Air Respirator (Airline) · Full facepiece · Continuous flow | 1,000 | 2,300IDLH |
| Supplied-Air Respirator (Airline) · Full facepiece · Pressure-demand / positive-pressure | 1,000 | 2,300IDLH |
| Self-Contained Breathing Apparatus · Full facepiece · Pressure-demand / positive-pressure | 10,000 | 2,300IDLH |
Notes
NIOSH REL is Ca [See Appendix A] — potential occupational carcinogen, no numeric REL (reduce to lowest feasible concentration); nioshREL field intentionally omitted. OSHA PEL TWA 25 ppm ST 125 ppm (substance-specific standard 1910.1052). IDLH Ca [2,300 ppm]. MW 84.9; conversion 1 ppm = 3.47 mg/m3.
Sources
- https://www.cdc.gov/niosh/npg/npgd0414.html
- https://www.cdc.gov/niosh/idlh/75092.html
- https://www.osha.gov/annotated-pels/table-z-1
Data confidence: high. Values are cited from OSHA and NIOSH but should be verified against the current source and a qualified professional before use. See how this works.