WHAT YOU NEED TO KNOW: As temperatures rise across California, employers must be prepared to protect workers from heat illness. 

Heat Illness Prevention Requirements

Cal/OSHA investigates heat-related incidents and complaints of hazards at outdoor worksites in industries such as agriculture, landscaping, and construction. These investigations ensure compliance with the heat illness prevention standard and the injury and illness prevention standard, which require employers with outdoor workers to take these precautions:

• Plan – Develop and implement an effective written heat illness prevention plan that includes emergency response procedures.
• Training – Train all employees and supervisors on heat illness prevention.
• Water – Provide drinking water that is fresh, pure, suitably cool and free of charge so each worker can drink at least 1 quart per hour and encourage workers to do so. 
• Rest – Encourage workers to take a cool-down rest in the shade for at least five minutes when they feel the need to do so to protect themselves from overheating. Workers should not wait until they feel sick to cool down.
• Shade – Provide proper shade when temperatures exceed 80 degrees. Workers have the right to request and be provided shade to cool off at any time. 
• Observe – Closely observe all employees during a heat wave and any employee newly assigned to a high heat area. Lighter work, frequent breaks or shorter hours will help employees who have not been working in high temperatures adapt to the new conditions.

Additional information about heat illness prevention are posted on Cal/OSHA’s Heat Illness Prevention page. Cal/OSHA also has extensive multilingual materials for employers, workers, and trainers on its Water. Rest. Shade. public awareness campaign website. A heat illness prevention regulation for indoor places of employment is currently being developed. Employers are advised that the existing Heat Illness Prevention Special Emphasis Program includes enforcement activities and multilingual outreach and training. Cal/OSHA will also continue investigating potential indoor heat violations under existing regulations such as the Injury and Illness Prevention Program (Title 8, Section 3203) and Water Supply (Title 8, Section 3363).

WHY IT MATTERS: Not only can workers be protected from heat exhaustion and issues like dizziness, weakness, and nausea, but they also can be protected from heat stroke, convulsions, fainting or potentially from death.

What Cal/OSHA Acting Chief Debra Lee said: “Employers with outdoor workers should not wait to review their procedures on preventing heat illness and they should ensure their training is effective as soon as possible.”

Need Help Staying Compliant with California Heat Safety Rules?
Heat illness prevention is just one part of creating a safe, legally compliant workplace. At Consult HR Services, we help small businesses like yours build smart, proactive HR practices—from safety planning to training and documentation.

If you’re not sure where to start, check out our blog on “Is Your Business HR Compliant? A Simple Checklist for 2025” to make sure you’re covering the basics. Need to revisit your safety protocols or job roles? Don’t miss “Why Outdated or Missing Job Descriptions Are a Big HR Red Flag”.

For hands-on support or to build your compliance strategy, get in touch with Consult HR Services — your trusted HR partner for California businesses.