If you have ever stacked boxes in a warehouse with no air conditioning, worked a grill through a lunch rush, or spent an August afternoon on a construction site in the Central Valley, you already know what this article is about. Heat at work is not just uncomfortable. It can make people dizzy, confused, and seriously ill, and in the worst cases it kills. California has some of the strongest workplace heat rules in the country, covering both outdoor and indoor jobs, but many workers have never been told what those rules actually say.
With triple-digit temperatures already hitting the state this summer, and Cal/OSHA publicly reminding employers of their obligations, this is a good moment to walk through what the law requires, what workers can do when a workplace feels dangerously hot, and what employers need to have in place before the next heat wave, not after.
Cal/OSHA Has Already Put Employers on Notice This Summer
On June 10, 2026, Cal/OSHA, the state agency that enforces workplace safety laws, issued an advisory reminding employers across California to protect workers from heat illness as the National Weather Service posted heat advisories for the Sacramento Valley, Mendocino, the inland Bay Area, and the Central Valley, with triple-digit temperatures in the forecast.
That advisory was not a suggestion. Cal/OSHA runs a heat illness prevention special emphasis program that includes active enforcement of the heat standards, and inspectors do show up at worksites during heat waves. Employers who have not prepared can face citations and penalties. Workers who are getting sick in the heat have a clear set of rights they can point to.
California actually has two separate heat rules, one for outdoor work and one for indoor work. Here is what each one requires, in plain English.
Outdoor Workers: Water, Shade, and the Right to Cool Down
California's outdoor heat illness prevention standard, found at Title 8, Section 3395 of the California Code of Regulations, has been protecting outdoor workers for years. It applies to outdoor workplaces generally, which includes farms, construction sites, landscaping crews, delivery routes, and outdoor events. The core requirements are:
- Fresh, cool drinking water, free of charge. Water must be located as close as practical to where people are working. Being told to bring your own or buy it from a vending machine generally does not satisfy the rule.
- Shade whenever the temperature passes 80 degrees. Once it is above 80 degrees, shade must actually be up and available, not just possible on request. Below 80 degrees, workers can still ask for shade and the employer must provide it.
- Cool-down rest breaks on request. A worker who feels the need to cool down can take a preventative rest break in the shade, and that break is in addition to regular rest breaks. Employers are required to monitor workers on cool-down breaks for signs of heat illness.
- Extra protections at 95 degrees. In certain industries, including agriculture, construction, landscaping, oil and gas extraction, and transportation of agricultural or construction materials, employers must follow high-heat procedures once the temperature reaches 95 degrees. These include regularly observing workers for heat illness symptoms and keeping effective communication going, so nobody suffers alone at the far end of a field.
- An acclimatization period. New workers, and workers newly assigned to hot jobs, must be closely observed during their first 14 days, and all workers must be observed closely during a heat wave. Bodies need time to adjust to heat, and many serious heat illnesses happen in a worker's first few days on the job.
Indoor Workers: The 82 Degree Rule
The newer of the two rules, and the one many people still have not heard about, covers indoor workplaces. Cal/OSHA's indoor heat illness prevention standard, Title 8, Section 3396, took effect in July 2024 and applies to most indoor workplaces when the inside temperature reaches 82 degrees. Think restaurants, warehouses, manufacturing plants, laundries, and kitchens.
Once an indoor workplace hits 82 degrees, the employer generally must provide:
- Fresh, cool drinking water, close to work areas and cool-down areas, at no cost.
- At least one cool-down area kept below 82 degrees, shielded from direct sunlight and other high-radiant heat sources, and large enough for workers on break to sit comfortably.
- Cool-down rest periods on request, just like the outdoor rule, with monitoring for symptoms.
The rule adds a second layer at higher temperatures. When the indoor temperature or heat index reaches 87 degrees, or 82 degrees where workers wear clothing that restricts heat removal or work in high-radiant-heat areas, the employer must measure and record the temperature and heat index, and must implement control measures to bring the risk down. Feasible engineering controls, meaning things like air conditioning, fans, ventilation, or heat shielding, come first. Administrative fixes like schedule changes and rotating workers come after that.
Both rules also require a written heat illness prevention plan and real training, for workers and for supervisors, on recognizing the symptoms of heat illness and responding to emergencies. If you have never received heat training at a job where heat is a regular reality, that gap is itself a compliance problem.
What Workers Can Do When It Is Too Hot
Knowing the rules is one thing. Using them at a real job, with a real boss, is another. Here are steps that generally make sense if your workplace is getting dangerously hot:
- Say something early, and keep it factual. A simple, specific report, like "the thermostat in the back reads 88 and there is no fan," is easier to act on and harder to ignore than a general complaint. Raising the issue internally first often gets it fixed fastest.
- Use your cool-down rights. The law gives workers the right to ask for a cool-down break when they feel the heat getting to them. Headache, dizziness, heavy sweating, and cramps are warning signs that a break is needed now, not at the next scheduled rest period.
- Write things down. Note dates, temperatures if you can see them, what you reported, and who you told. Our guide on documenting workplace issues explains how to build a record that holds up.
- Know where to report. Workers can call Cal/OSHA at 833-579-0927 to speak with a bilingual representative, or file a complaint with a Cal/OSHA district office. By law, the division keeps the complaining worker's name confidential unless the worker says otherwise, and these protections apply regardless of immigration status.
- Retaliation for raising safety concerns is illegal. California Labor Code Section 6310 prohibits firing or punishing a worker for making a safety complaint to the employer or to a government agency, and a worker who is retaliated against may be entitled to reinstatement and lost wages. If something changes at work right after you raise a heat concern, our article on the signs of workplace retaliation covers what that can look like.
What This Means for Employers
For employers, the practical message of the June advisory is that heat compliance is a now problem, not a someday problem. A heat wave is the worst possible time to discover that your written plan is a blank template. Steps worth taking before the next hot stretch:
- Have a written heat illness prevention plan that matches your actual worksite, outdoor, indoor, or both. Many businesses, like a restaurant with a patio or a warehouse with a loading dock, may be covered by both standards at once.
- Train supervisors first. Supervisors are the ones who decide in the moment whether someone gets a break, and they need to know how to check weather reports, spot symptoms, and respond to an emergency.
- Fix the easy things now. Water stations, shade structures, fans, and a cool break room are inexpensive compared to a citation, a workers' compensation claim, or a serious injury.
- Watch the thermometer indoors. The measurement and recordkeeping duties at 87 degrees are specific, and skipping them is one of the more visible violations an inspector can find.
- Take complaints as information, not insubordination. A worker who tells you the kitchen is too hot is giving you a chance to fix a hazard before Cal/OSHA or a lawyer is involved. Responding badly can turn a fixable safety issue into a retaliation claim, which is usually a far more expensive problem.
- Use the free help. Cal/OSHA's Consultation Services Branch, at 800-963-9424, offers confidential assistance to employers separate from enforcement, and the state's Heat Illness Prevention page has model plans and training materials at no cost.
When a Heat Complaint Becomes a Workplace Dispute
Most heat issues get fixed with a fan, a schedule change, or a working thermostat. But some do not, and the pattern is familiar. A worker raises a concern, feels brushed off, and raises it louder. A manager feels accused and gets defensive. Hours get cut, or a write-up appears, and suddenly a fixable safety issue has hardened into a dispute about retaliation, with both sides bracing for a fight.
That escalation is not inevitable. It usually happens because there was no neutral, confidential place to talk before positions locked in. This is the gap Wiser Workplace was built for. Our California-based platform gives employees a confidential way to raise a workplace concern, and gives employers a structured way to hear it and respond, with a neutral mediator available when the two sides need help getting to a resolution. We are not a law firm and we do not give legal advice. What we offer is a faster, calmer path through a dispute, often at a fraction of the cost of litigation for everyone involved. If that sounds useful, you can read about the benefits of staying out of court or join the launch waitlist.
Summer 2026 is going to be hot. The rules that protect people at work in that heat are already on the books, and this is the season they matter most. For more on what changed in California workplaces this year, see our roundup of new California workplace laws for 2026.
Sources: California Department of Industrial Relations, Cal/OSHA heat illness advisory, Release No. 2026-47 (June 10, 2026); Cal/OSHA Heat Illness Prevention Guidance and Resources (dir.ca.gov); California Code of Regulations, Title 8, Sections 3395 and 3396; California Labor Code Sections 6309, 6310, and 6312.