# Magnesium oxide fume, as Mg — US workplace chemical exposure limits: federal OSHA vs Cal/OSHA, side by side

For Magnesium oxide fume, as Mg, pel (mg/m³) is 10, verified against its source on 2026-08-05.

- **Substance:** Magnesium oxide fume, as Mg
- **PEL (mg/m³):** 10

## What the source says

> 1309484 | | Magnesium oxide fume, as Mg | -- | 10

## Source

- 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/).