# Methyl bromide — US workplace chemical exposure limits: federal OSHA vs Cal/OSHA, side by side

For Methyl bromide, cas no. is 74-83-9; pel (ppm) is (C)20; pel (mg/m³) is (C)80, verified against its source on 2026-08-05.

- **Substance:** Methyl bromide
- **CAS No.:** 74-83-9
- **PEL (ppm):** (C)20
- **PEL (mg/m³):** (C)80

## What the source says

> Methyl bromide | 74-83-9 | (C)20 | (C)80 | X |

## 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.

### PEL (ppm)

osha.gov says pel (ppm) is **(C)20**, as of 2026-08-05.

> Methyl bromide | 74-83-9 | (C)20 | (C)80 | X |

Source: https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1

dir.ca.gov says pel (ppm) is **1**, as of 2026-08-05.

> 74839 | S | Methyl bromide | 1 | 3.88 | 20 ppm

Source: https://www.dir.ca.gov/title8/5155.html


### PEL (mg/m³)

osha.gov says pel (mg/m³) is **(C)80**, as of 2026-08-05.

> Methyl bromide | 74-83-9 | (C)20 | (C)80 | X |

Source: https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1

dir.ca.gov says pel (mg/m³) is **3.88**, as of 2026-08-05.

> 74839 | S | Methyl bromide | 1 | 3.88 | 20 ppm

Source: https://www.dir.ca.gov/title8/5155.html


## Source

- https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1
- https://www.dir.ca.gov/title8/5155.html

Last verified: 2026-08-05. Review by: 2027-08-05.
Part of [US workplace chemical exposure limits: federal OSHA vs Cal/OSHA, side by side](https://referencesource.org/workplace-exposure-limits/).