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ADVISORY
Release Number: 2024-54
Date: July 2, 2024

Cal/OSHA Urges Employers to Protect Workers during Extreme Heat Wave

Cal/OSHA is urging all employers to protect workers from heat illness as high temperatures are forecast for the first week of July across California.

Temperatures are expected to exceed 110°F in many parts of the state and are forecast to peak Thursday, July 4 through Saturday, July 6.

When working in hotter conditions, workers must be closely observed for any signs of heat illness.

In indoor workplaces, employers must correct unsafe conditions for workers created by heat as part of their Injury and Illness Prevention Program.

Employers in California must take steps to protect outdoor workers from heat illness by providing water, rest, shade and training.

Cal/OSHA’s heat illness prevention standard applies to all outdoor worksites. To prevent heat illness, the law requires employers to provide outdoor workers fresh water, access to shade at 80 degrees, and, whenever requested by a worker, cool-down rest breaks in addition to regular breaks. Employers must also maintain a written prevention plan with effective training for supervisors to recognize the common signs and symptoms of heat illness, and what to do in case of an emergency.

In certain industries, when the temperature at outdoor worksites reaches or exceeds 95 degrees, Cal/OSHA’s standard requires additional protections. The industries with additional high-heat requirements are agriculture, construction, landscaping, oil and gas extraction, and transportation of agricultural products, construction materials or other heavy materials. High-heat procedures include ensuring employees are observed regularly for signs of heat illness and establishing effective communication methods so workers can contact a supervisor when needed.

Employers with outdoor workers in all industries must take the following steps to prevent heat illness:

Cal/OSHA Urges Employers to Protect Workers Amid Forecast Heat Wave

  • 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 that each worker can drink at least 32 ounces (or four cups of water) 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.

Cal/OSHA’s Heat Illness Prevention special emphasis program includes enforcement of the heat regulation as well as multilingual outreach and training programs for California’s employers and workers. Details on heat illness prevention requirements and training materials are available online on

Cal/OSHA’s Heat Illness Prevention web page and the 99calor.org informational website. A Heat Illness Prevention online tool is also available on Cal/OSHA’s website.

Cal/OSHA helps protect workers from health and safety hazards on the job in almost every workplace in California. Employers who have questions or need assistance with workplace health and safety programs can call Cal/OSHA’s Consultation Services Branch at 800-963-9424.

Workers who have questions about heat illness prevention in indoor and outdoor places of employment can call 833-579-0927 to speak with a bilingual Cal/OSHA representative Monday through Friday from 9 a.m. to 7 p.m. Complaints about workplace safety and health hazards can be filed confidentially with Cal/OSHA district offices.

Cal/OSHA has established the Heat Illness Prevention (HIP) Network, a voluntary partnership aimed at increasing awareness among employers and workers about the importance of preventing heat illness in California and the importance of taking steps to prevent work-related illnesses and fatalities. To join the HIP Network, email HIPNetwork@dir.ca.gov.