Every state heat safety regulation in one place, updated 12 August 2026
Short answer: seven states have enforceable worker heat safety laws. California, Washington, Oregon, Maryland, Nevada, Minnesota, and Colorado. Four of them cover indoor work. Everywhere else, federal OSHA is the rule, and it still cites employers who ignore heat.
Pick your state
Seven states have enforceable heat regulations. Three have laws that block local ones. Everywhere else, federal OSHA is the rule. Open your state for the trigger temperatures, what the regulation requires, and how to document it.
Triggers are heat index unless noted. Minnesota is measured in WBGT, which folds in humidity and radiant heat, so its numbers are stricter than they look. Verify against your state agency before writing a plan.
The map
| State | Enforceable rule? | Trigger | Indoor? | What it turns on |
|---|---|---|---|---|
| California | Yes | 80°F out / 82°F in | Yes | Title 8 §3395 outdoor and §3396 indoor. Written IHIPP, shade, water, cool-down. |
| Washington | Yes | 80°F | Outdoor | WAC 296-62-095. Applies year-round, not just summer. |
| Oregon | Yes | 80°F / 90°F | Yes | OAR 437. Paid cool-down periods become mandatory at the high-heat tier. |
| Maryland | Yes | 80°F / 90°F | Yes | MOSH 2024. One of the newest, and it covers indoor work from the start. |
| Nevada | Yes | Hazard assessment | Yes | 2024 rule. No single thermometer number; a written assessment sets the trigger. |
| Minnesota | Yes | 77 to 86°F WBGT | Indoor only | Rules 5205.0110. Hard indoor limits by workload. Among the oldest in the country. |
| Colorado | Yes | 80°F (agriculture) | Yes | HB 26-1272 extended coverage to all industries on 12 Aug 2026, but thresholds are still phased in. |
| Texas | No | Federal only | n/a | HB 2127 preempts local water-break ordinances. Upheld on appeal in July 2025. |
| Florida | No | Federal only | n/a | HB 433 blocks local heat protections. Gulf humidity makes the heat index the real number. |
| Arizona | No | Federal only | n/a | No standard, but ADOSH runs a Heat Stress Emphasis Program with targeted inspections. |
| Everywhere else | Proposed | 80°F / 90°F | Yes | Federal NPRM stalled. General Duty Clause and the Heat NEP still apply in full. |
Triggers are heat index unless noted. Minnesota is measured in WBGT, which folds in humidity and radiant heat, so its numbers are stricter than they look. Verify against your state agency before writing a plan.
What the map actually tells you
The number everyone converged on
California, Oregon, Maryland, Colorado agriculture, and the stalled federal rule all start at 80°F, with a high-heat tier at 90°F. If you run one program at those triggers, you are close to compliant almost everywhere.
The fastest-moving frontier
Five of the seven rules now reach indoor work. Warehouses, foundries, and plant floors were the blind spot, and regulators are closing it. If your heat plan stops at the door, it is out of date.
States where heat is not citable
Preemption laws stop cities, not OSHA. In Texas, Florida, and Arizona the General Duty Clause still applies, and a heat fatality still brings a citation. "No rule" is not a defense anyone has won with.
FAQ
Summer 2026, 500-unit first batch