---
type: threshold
id: hafnium
asset: workplace-exposure-limits
title: "Hafnium — 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: "Hafnium | 7440-58-6 | - | 0.5 | - |"
generated: true
harvested: 2026-08-05
stale_after: 2027-08-05
substance: "Hafnium"
cas_number: "7440-58-6"
pel_mgm3: "0.5"
verified: true
---
**Substance:** Hafnium

**CAS No.:** 7440-58-6

**PEL (mg/m³):** 0.5

> Hafnium | 7440-58-6 | - | 0.5 | - |

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