With summer unofficially starting and temperatures in areas throughout California recently reaching near or over 100 degrees Fahrenheit, Cal/OSHA is urging employers to help protect workers from heat illness at both outdoor and indoor worksites. Because heat illness is a serious and potentially deadly hazard, employers are mandated to implement protective measures for their employees. Cal/OSHA’s Heat Illness Prevention Standards specify what measures should be taken for both indoor and outdoor employees to prevent worker exposure to heat illness.

The regulations governing heat illness prevention in indoor places of employment went into effect on July 23, 2024. These standards apply to most workplaces, such as restaurants, warehouses, and manufacturing facilities, where the indoor temperature reaches 82 degrees Fahrenheit. Requirements include providing water, rest, cool-down areas, and training.

For outdoor worksites, the heat illness prevention regulations require employers to provide the following:

• Water – Access to fresh and cool water so that each worker can drink at least 32 ounces of water per hour.
• Rest– A preventative cool-down rest in the shade is allowed whenever workers feel the need to prevent themselves from overheating.
• Shade– Workers may request access to shade anytime, and employers must provide it. A shaded area must be present when temperature exceeds 80 degrees.

In industries relating to agriculture, construction, landscaping, oil and gas extraction, and transportation of agricultural products, construction materials, or other heavy materials, Cal/OSHA requires additional high-heat protections when the temperatures at outdoor worksites reaches 95 degrees. The high heat standard includes ensuring employees are observed regularly for signs of heat illness and establishing effective communication methods. 

Employers with either indoor or outdoor worksites must maintain a written prevention plan and facilitate effective training for supervisors to recognize the common signs and symptoms of heat illness and the steps to take in case of an emergency. The prevention plan must be written in English and in the language understood by the majority of the employees, and made available to employees at the worksite.

Cal/OSHA has numerous resource for employers including a Comparison Chart of Indoor and Outdoor Heat Illness Prevention Standards and a Heat Illness Prevention online tool. In addition, 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.