---
type: threshold
id: hydroquinone
asset: workplace-exposure-limits
title: "Hydroquinone — US workplace chemical exposure limits: federal OSHA vs Cal/OSHA, side by side"
sources:
  - https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1
source_quote: "Hydroquinone | 123-31-9 | - | 2 | - |"
generated: true
harvested: 2026-08-05
stale_after: 2027-08-05
substance: "Hydroquinone"
cas_number: "123-31-9"
pel_mgm3: "2"
verified: true
---
**Substance:** Hydroquinone

**CAS No.:** 123-31-9

**PEL (mg/m³):** 2

> Hydroquinone | 123-31-9 | - | 2 | - |

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