In the United States there is no single national heat rule for all workplaces. This lesson explains what the law does say, and where it is changing. The facts are those known in October 2026.
The General Duty Clause
The Occupational Safety and Health Act of 1970 applies to most private employers. Section 5(a)(1), the General Duty Clause, says an employer must give workers a workplace free from recognized hazards that are causing or likely to cause death or serious physical harm.
Heat is a recognized hazard. OSHA can cite an employer under the General Duty Clause when workers are exposed to heat and the employer does not take reasonable steps to protect them.
No final federal heat standard (yet)
In August 2024 federal OSHA published a proposed rule called Heat Injury and Illness Prevention in Outdoor and Indoor Work Settings. It would cover most workplaces, indoor and outdoor, and would require employers to have a written heat plan. Public hearings were held in 2025 and the last comment period closed in October 2025. When this course was written (October 2026) the rule was still a proposal: no final rule had been published. A proposal is not law. Watch the Federal Register and osha.gov for news.
OSHA's National Emphasis Program
OSHA also runs a National Emphasis Program on outdoor and indoor heat-related hazards. It lets OSHA start inspections in high-risk industries without waiting for a complaint. It began in 2022, and OSHA issued a revised version in April 2026. Employers with workers in hot conditions should expect to be asked what they do to protect them.
State rules
About half the states run their own OSHA-approved state plans, and some states have made their own heat rules. These differ from state to state, so check the one that covers your job. Examples:
- California has two standards: Title 8, section 3395 for outdoor work and section 3396 for indoor work.
- Washington has outdoor heat exposure rules in the WAC 296-62-095 series, last updated in July 2023.
- Oregon has a heat illness prevention rule, OAR 437-002-0156, for indoor and outdoor work.
- Maryland has a heat stress standard, COMAR 09.12.32, in force since September 2024.
- Nevada adopted a heat illness prevention regulation in 2024 (NAC chapter 618).
- Colorado has heat rules for agricultural workers.
- Minnesota has limits for heat in indoor workplaces in its safety rules.
These rules change. This course does not list every state, and it does not give you legal advice. Your employer, your state OSHA office or the state labor department can tell you what applies.
Your rights
Under federal law you have the right to:
- a workplace free from recognized hazards, including heat,
- training you understand, from your employer,
- ask your employer to fix a hazard, or file a complaint with OSHA (1-800-321-OSHA, or osha.gov),
- not be punished for raising a safety concern. Section 11(c) of the OSH Act protects you. If you are fired or punished, you generally have 30 days to file a complaint with OSHA. Some state plans have different times.
What your employer must still do
The law, a state rule or a company policy decides what your employer must do. At minimum, a good employer plans for heat, trains workers, gives water and rest, and responds to emergencies. This course does not replace that.
What to remember
- Federal law has the General Duty Clause, but no final heat standard as of October 2026.
- OSHA's National Emphasis Program targets heat hazards.
- Some states have their own heat rules, and these differ.
- You may raise heat concerns without punishment.