Compliance guideRead at source, 23 September 2026
Heat Illness Prevention Plans: What Employers in California, Washington, Oregon and Other States Must Have in 2026
A heat illness prevention plan is the written program an employer uses to prevent heat illness: water, shade, rest, acclimatization of new workers, training, and emergency response. There is no final federal heat standard — OSHA proposed one in August 2024 and now projects a supplemental proposal for December 2026 — but several states require a plan today. California requires one for outdoor work (shade above 80°F) and, since July 2024, indoor work at 82°F and above. Washington triggers at 80°F outdoors, Oregon and Maryland at a heat index of 80°F, and Nevada requires a job hazard analysis for employers with more than 10 employees. The employer side is a plan, a trigger, and a new-hire rule — not a list of symptoms.
Who needs a heat illness prevention plan
If you have employees working outdoors or in hot indoor spaces in a state with a heat standard, you need a written plan. Everywhere else, OSHA can still cite serious heat hazards under the General Duty Clause, and in April 2026 it renewed its National Emphasis Program on heat for five years, so inspections focused on heat will continue whatever happens to the federal rule. A written plan is the evidence that you had a program.
State heat standards at a glance
| State | Scope | Main trigger | High-heat or extra measures |
|---|---|---|---|
| California (outdoor) | All outdoor places of employment; 8 CCR 3395 | Shade when the temperature exceeds 80°F | High-heat procedures at 95°F for agriculture, construction, landscaping, oil and gas, and certain transport |
| California (indoor) | Indoor work areas at 82°F or above; 8 CCR 3396, operative July 23, 2024 | 82°F with employees present | Assessment and controls at 87°F (temperature or heat index), or 82°F with restrictive clothing or high radiant heat |
| Washington | Outdoor work; agriculture covered separately | 80°F (52°F with non-breathable clothing or chemical suits) | At 90°F: paid 10-minute cool-down every 2 hours; at 100°F: 15 minutes every hour |
| Oregon | Indoor and outdoor; OAR 437-002-0156 | Heat index 80°F | High-heat practices at heat index 90°F, with minimum rest schedules |
| Maryland | Indoor and outdoor; effective September 30, 2024 | Heat index 80°F | Rest breaks at heat index 90°F and above, increasing above 100°F |
| Nevada | Employers with more than 10 employees | No fixed temperature; one-time job hazard analysis | Written safety program where hazards are found |
| Colorado | Agriculture (7 CCR 1103-15); HB26-1272, signed June 4, 2026, extends the state’s extreme-temperature work to all workers | 80°F for agricultural work | At 95°F: at least 10 minutes’ rest per two hours of work. Readings of what HB26-1272 requires of non-agricultural employers differ; check the enacted act |
| Minnesota | Indoor work; Minn. R. 5205.0110 | Wet-bulb globe temperature limits by workload (77–86°F WBGT) | Training required |
New Mexico has a heat rule in rulemaking; the state environment department has asked to move the hearing to March 2027. Check your state’s occupational safety agency for anything adopted after this page was read.
What California requires, in detail
California’s outdoor rule is the model most other states have borrowed from, and it is the one most employers are measured against.
- Water. Enough fresh, cool water for “one quart per employee per hour for drinking for the entire shift,” located as close as practicable to where people work.
- Shade. Shade must be present when the temperature exceeds 80°F, enough for everyone on a rest or meal break.
- Cool-down rest. An employee may take a preventative cool-down rest in the shade when they feel the need, for at least five minutes plus the time to get there.
- High heat. At 95°F or above, covered industries must use high-heat procedures: effective communication, pre-shift meetings, observation for symptoms, a designated person to call for emergency help, and reminders to drink water. Agriculture must also give a ten-minute preventative cool-down every two hours.
- Acclimatization. During a heat wave, all employees are closely observed; newly assigned employees in high heat are observed for their first 14 days.
- Training. Before employees and supervisors are exposed to the risk.
- Written plan. In English and in the language understood by most of the employees, available at the worksite.
The indoor rule adds measurement, records and engineering controls: in covered indoor areas at 87°F, employers must assess and control heat, keep cool-down areas below 82°F where feasible, and keep measurement records for 12 months or until the next measurements.
The federal rule: where it stands
OSHA published its proposed Heat Injury and Illness Prevention in Outdoor and Indoor Work Settings rule on August 30, 2024. It would apply an initial trigger at a heat index of 80°F and a high-heat trigger at 90°F, with a paid 15-minute rest break at least every two hours at high heat. OSHA held an informal public hearing from June 16 to July 2, 2025 and extended the post-hearing comment period to October 30, 2025. As of September 2026 the rule is neither final nor withdrawn; the regulatory agenda projects a supplemental proposal in December 2026 and final action in October 2027. Plan against your state’s rule now, and treat the federal triggers as the likely direction.
What goes in the plan: an outline
1. Scope and responsibility
Sites and tasks covered; the person responsible at each site; who can stop work.
2. Monitoring
How temperature or heat index is checked (forecast plus on-site reading), when, by whom, and where it is recorded.
3. Water, shade and rest
Water quantity and location; shade setup and the temperature that triggers it; the cool-down rest rule and schedule at high heat.
4. Acclimatization
The first-two-weeks rule for new and returning employees: reduced exposure, a buddy, close observation.
5. Training
Before exposure and annually: risk factors, symptoms, the right to rest, how to report, and emergency procedures. In the languages your crew speaks.
6. Emergency response
How to call for help from each site, the address or directions for responders, and first aid until they arrive.
Why new hires are the risk, and what that means for hiring
Most of the state rules above single out new workers, because they have not acclimatized. For employers who hire most of their crew in late spring, the busiest hiring weeks are also the highest-risk weeks for heat illness. Two practical consequences: start hiring earlier, so new crew members acclimatize in cooler weeks, and build the first-two-weeks rule into the schedule from day one. Our page on peak season staffing covers the hiring calendar; for farm crews, see the farm labor shortage page.
Frequently asked questions
Is there a federal heat illness standard?
Not yet. OSHA proposed a heat injury and illness prevention rule in August 2024 with a heat index trigger of 80 degrees F and a high-heat trigger of 90 degrees F. As of September 2026 it is not final; the regulatory agenda projects a supplemental proposal in December 2026. OSHA can still cite heat hazards under the General Duty Clause.
Which states have heat illness prevention rules?
California (outdoor and indoor), Washington (outdoor), Oregon, Maryland, Nevada, Colorado for agriculture (with a 2026 law, HB26-1272, extending its extreme-temperature program to all workers), and Minnesota for indoor work. New Mexico has a rule in rulemaking.
What temperature requires shade for workers in California?
Under 8 CCR 3395, shade must be present when the temperature exceeds 80 degrees Fahrenheit. High-heat procedures apply at 95 degrees in agriculture, construction, landscaping, oil and gas extraction and certain transport.
What does California require for indoor heat?
Under 8 CCR 3396, operative July 23, 2024, the rule covers indoor work areas at 82 degrees F or above. At 87 degrees (temperature or heat index), or 82 degrees with restrictive clothing or high radiant heat, employers must assess and control the heat, provide cool-down areas and keep measurement records.
How much water must employers provide for heat illness prevention?
California requires enough fresh, cool water for one quart per employee per hour for the entire shift. Oregon and Maryland require enough for employees to drink 32 ounces an hour.
What should a heat illness prevention plan include?
Who is responsible, how heat is monitored, water, shade and rest provisions, an acclimatization rule for new workers, training before exposure, and emergency response procedures. California requires the written plan in English and in the language understood by most employees.
Why are new workers at higher risk of heat illness?
They have not acclimatized to working in heat. State rules require closer observation of new employees, such as California’s 14-day observation for newly assigned employees in high heat, and hiring earlier in the season gives new crew members time to adjust.
Hire the summer crew before the heat arrives.
Boostpoint runs local Facebook and Instagram recruitment campaigns for trades, agriculture and warehouse employers, timed so new hires start in cooler weeks.
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