Methyl iodide — CAS 74-88-4 — workplace exposure limit
What is the pel (ppm) for Methyl iodide — CAS 74-88-4 — workplace exposure limit?
For Methyl iodide, pel (ppm) is disputed: 5 per osha.gov, 2 per dir.ca.gov; pel (mg/m³) is disputed: 28 per osha.gov, 10 per dir.ca.gov; cas no. is 74-88-4, verified against its source on 2026-08-05.
Methyl iodide | 74-88-4 | 5 | 28 | X |
— osha.gov, retrieved 2026-08-05
- Substance
- Methyl iodide verified
- CAS No.
- 74-88-4 verified
- PEL (ppm)
- 5 sources disagree
- PEL (mg/m³)
- 28 sources disagree
- NIOSH REL (ppm)
- TWA 2 per cdc.gov
- NIOSH REL (mg/m³)
- 10 per cdc.gov
What cdc.gov says
NIOSH REL Ca TWA 2 ppm (10 mg/m3) [skin]
— cdc.gov, retrieved 2026-09-08
Substance
CDC - NIOSH Pocket Guide to Chemical Hazards - Methyl iodide
CAS No.
CAS No. 74-88-4
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 5, as of 2026-08-05.
Methyl iodide | 74-88-4 | 5 | 28 | X |
https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1
dir.ca.gov says pel (ppm) is 2, as of 2026-08-05.
74884 | S | Methyl iodide | 2 | 10
https://www.dir.ca.gov/title8/5155.html
PEL (mg/m³)
osha.gov says pel (mg/m³) is 28, as of 2026-08-05.
Methyl iodide | 74-88-4 | 5 | 28 | X |
https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1
dir.ca.gov says pel (mg/m³) is 10, as of 2026-08-05.
74884 | S | Methyl iodide | 2 | 10
Sources
- osha.govhttps://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1
- dir.ca.govhttps://www.dir.ca.gov/title8/5155.html
- cdc.govhttps://www.cdc.gov/niosh/npg/npgd0420.html