Methyl mercaptan
For Methyl mercaptan, cas no. is 74-93-1; pel (ppm) is (C)10; pel (mg/m³) is (C)20, verified against its source on 2026-08-05.
- Substance
- Methyl mercaptan
- CAS No.
- 74-93-1
- PEL (ppm)
- (C)10
- PEL (mg/m³)
- (C)20
What the source says
Methyl mercaptan | 74-93-1 | (C)10 | (C)20 | - |
— osha.gov, retrieved 2026-08-05
Sources disagree
More than one authority states this, and they do not state the same thing. Both are reproduced with the source each came from — deciding between them is yours, not ours.
PEL (ppm)
osha.gov says pel (ppm) is (C)10, as of 2026-08-05.
Methyl mercaptan | 74-93-1 | (C)10 | (C)20 | - |
https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1
dir.ca.gov says pel (ppm) is 0.5, as of 2026-08-05.
74931 | | Methyl mercaptan | 0.5 | 1
https://www.dir.ca.gov/title8/5155.html
PEL (mg/m³)
osha.gov says pel (mg/m³) is (C)20, as of 2026-08-05.
Methyl mercaptan | 74-93-1 | (C)10 | (C)20 | - |
https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1
dir.ca.gov says pel (mg/m³) is 1, as of 2026-08-05.
74931 | | Methyl mercaptan | 0.5 | 1
Sources
- osha.govhttps://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1
- dir.ca.govhttps://www.dir.ca.gov/title8/5155.html