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

For Pentachloronaphthalene, cas no. is 1321-64-8; pel (mg/m³) is 0.5, verified against its source on 2026-08-05.

- **Substance:** Pentachloronaphthalene
- **CAS No.:** 1321-64-8
- **PEL (mg/m³):** 0.5

## What the source says

> Pentachloronaphthalene | 1321-64-8 | - | 0.5 | X |

## 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/).