Summer is roughly two months away. If you have outdoor workers -- construction, landscaping, road work, agriculture, any of it -- now is the time to get your heat safety program in order. Because the regulatory landscape is shifting, and being unprepared is going to cost you.
OSHA has been working toward the first comprehensive federal heat injury and illness prevention standard in U.S. history. The proposed rule covers both outdoor and indoor work settings and will create enforceable employer obligations where previously there were only recommendations.
The rule sets two key temperature trigger points. At a heat index of 80 degrees Fahrenheit, initial protective requirements kick in. At 90 degrees Fahrenheit, high-heat procedures become mandatory. Think about how often your sites hit those numbers from May through September. For most of the country, it is a lot.
The final rule has not been published yet, but Cal/OSHA already has requirements in place for California employers -- and those standards give us a clear preview of where the federal rule is headed. Under California's standard, shade must be available when temperatures reach 80 degrees. Workers can request cool-down rest breaks at any time. At 95 degrees and above, additional protections are required.
Heat-related illness is the leading cause of weather-related death in the United States. Workers suffer heat exhaustion, heat stroke, and heat syncope at rates that have only climbed as temperatures have risen. These are not freak accidents. They are predictable and preventable.
The workers most at risk: new or returning employees who have not yet acclimatized, anyone wearing heavy PPE, and anyone doing physically intense labor outdoors. Your first two weeks with a new crew member during hot weather are the most dangerous period. That is when you need to be watching.
OSHA is also hosting a Safety Stand-Down webinar on April 8th to help employers prepare for the 2026 National Work Zone Awareness Week safety events. Free resources, compliance assistance, and guidance on hosting your own stand-down are available through OSHA's Safety Champions Program.
Best Practices and Tips for Heat Illness Prevention
Start with acclimatization:
- New workers and anyone returning after time off should not go straight to full workload in the heat. Build up exposure over 7 to 14 days.
- Reduce workload intensity for the first week. Increase it gradually as the body adjusts.
Water, shade, and rest -- the non-negotiables:
- Fresh, cool drinking water must be available at all times. One quart per worker per hour during heavy work in the heat is the general target.
- Shade structures must be available when temperatures are 80 degrees or higher. Do not make workers walk a quarter mile to find shade.
- Allow cool-down rest breaks whenever a worker feels overheated. In California, they must be provided on request. Make this your standard everywhere.
Know the warning signs:
- Heat exhaustion: heavy sweating, weakness, cold or pale clammy skin, weak pulse, nausea or vomiting, possible fainting.
- Heat stroke: high body temperature above 103 degrees, hot and red skin, rapid and strong pulse, unconsciousness. Call 911 immediately.
- Train your crew to recognize these. They are the ones who will spot it first.
Adjust your schedule:
- Schedule heavy physical work for the cooler parts of the day -- early morning or late afternoon.
- Watch the heat index, not just the temperature. Humidity makes it significantly more dangerous.
Use a buddy system:
- Pair workers so someone is always watching for signs of heat illness. Alone workers are the highest risk.
Get your written heat illness prevention plan done now, before the heat hits. Do not wait for a citation or a downed worker to make this a priority.