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

For Hydrogen chloride, cas no. is 7647-01-0; pel (ppm) is (C)5; pel (mg/m³) is (C)7, verified against its source on 2026-08-05.

- **Substance:** Hydrogen chloride
- **CAS No.:** 7647-01-0
- **PEL (ppm):** (C)5
- **PEL (mg/m³):** (C)7

## What the source says

> Hydrogen chloride | 7647-01-0 | (C)5 | (C)7 | - |

## 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)5**, as of 2026-08-05.

> Hydrogen chloride | 7647-01-0 | (C)5 | (C)7 | - |

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

dir.ca.gov says pel (ppm) is **0.3**, as of 2026-08-05.

> 7647010 | | Hydrogen chloride | 0.3 | 0.45 | 2 ppm

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


### PEL (mg/m³)

osha.gov says pel (mg/m³) is **(C)7**, as of 2026-08-05.

> Hydrogen chloride | 7647-01-0 | (C)5 | (C)7 | - |

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

dir.ca.gov says pel (mg/m³) is **0.45**, as of 2026-08-05.

> 7647010 | | Hydrogen chloride | 0.3 | 0.45 | 2 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/).