# n-Heptane — US workplace chemical exposure limits: federal OSHA vs Cal/OSHA, side by side

For n-Heptane, pel (ppm) is 400; pel (mg/m³) is 1,600; stel (ppm) is 500; stel (mg/m³) is 2000, verified against its source on 2026-08-05.

- **Substance:** n-Heptane
- **PEL (ppm):** 400
- **PEL (mg/m³):** 1,600
- **STEL (ppm):** 500
- **STEL (mg/m³):** 2000

## What the source says

> 142825 | | n-Heptane | 400 | 1,600 | | 500 | 2000

## 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/).