Ethylene oxide — workplace exposure limit
What is the niosh rel (ppm) for Ethylene oxide — workplace exposure limit?
For Ethylene oxide, niosh rel (ppm) is C 5; niosh rel (mg/m³) is 9; cas no. is 75-21-8, verified against its source on 2026-09-08.
NIOSH REL Ca TWA <0.1 ppm (0.18 mg/m3) C 5 ppm (9 mg/m3) [10-min/day]
— cdc.gov, retrieved 2026-09-08
- Substance
- Ethylene oxide verified
- CAS No.
- 75-21-8 verified
- NIOSH REL (ppm)
- C 5 verified
- NIOSH REL (mg/m³)
- 9 verified
- PEL (ppm)
- 1 per dir.ca.gov
- PEL (mg/m³)
- 2 per dir.ca.gov
- STEL (ppm)
- 5 per dir.ca.gov
Where each value comes from
This source states these in separate places, so each value is shown with the passage that states it.
Substance
CDC - NIOSH Pocket Guide to Chemical Hazards - Ethylene oxide
CAS No.
CAS No. 75-21-8
— all from cdc.gov, retrieved 2026-09-08
What osha.gov says
Ethylene oxide; see 1910.1047 | 75-21-8 | - | - | - |
— osha.gov, retrieved 2026-08-05
What dir.ca.gov says
75218 | | Ethylene oxide; see Section 5220 | 1 | 2 | | 5
— dir.ca.gov, retrieved 2026-08-05
Sources
- cdc.govhttps://www.cdc.gov/niosh/npg/npgd0275.html
- osha.govhttps://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1
- dir.ca.govhttps://www.dir.ca.gov/title8/5155.html