# Hazardous waste operations and emergency response (HAZWOPER) — OSHA medical surveillance trigger thresholds by substance

For Hazardous waste operations and emergency response (HAZWOPER), cfr section is 1910.120; action level is none defined; pel is none defined; surveillance trigger is Employees exposed to hazardous substances or health hazards at or above the PEL (or published exposure levels if no PEL) for 30 days or more per year; employees who wear a respirator for 30 days or more per year; employees who are injured or develop signs or symptoms from overexposure; members of HAZMAT teams; exam frequency is Prior to assignment; at least once every twelve months unless physician believes a longer interval (not greater than biennially) is appropriate; at termination if no exam within last six months; as soon as possible after emergency incident or development of signs or symptoms, recorded from its source on 2026-08-12.

- **Substance:** Hazardous waste operations and emergency response (HAZWOPER)
- **CFR section:** 1910.120
- **Action level:** none defined
- **PEL:** none defined
- **Surveillance trigger:** Employees exposed to hazardous substances or health hazards at or above the PEL (or published exposure levels if no PEL) for 30 days or more per year; employees who wear a respirator for 30 days or more per year; employees who are injured or develop signs or symptoms from overexposure; members of HAZMAT teams
- **Exam frequency:** Prior to assignment; at least once every twelve months unless physician believes a longer interval (not greater than biennially) is appropriate; at termination if no exam within last six months; as soon as possible after emergency incident or development of signs or symptoms
- **Record retention:** Retained for the period specified and meeting the criteria of 29 CFR 1910.1020

## What the source says

> All employees who are or may be exposed to hazardous substances or health hazards at or above the permissible exposure limits or, if there is no permissible exposure limit , above the published exposure levels for these substances , without regard to the use of respirators , for 30 days or more a year

## Source

- https://www.law.cornell.edu/cfr/text/29/1910.120

Last verified: 2026-08-12. Review by: 2027-02-08.
Part of [OSHA medical surveillance trigger thresholds by substance](https://referencesource.org/osha-medical-surveillance-triggers/).