08/25/2026
Millions of U.S. workers are exposed to heat in their workplaces. Although illness from exposure to heat is preventable, every year, thousands become sick from occupational heat exposure, and some cases are fatal. Most outdoor fatalities, 50% to 70%, occur in the first few days of working in warm or hot environments because the body needs to build a tolerance to the heat gradually over time. The process of building tolerance is called heat acclimatization. Lack of acclimatization represents a major risk factor for fatal outcomes.
Occupational risk factors for heat illness include heavy physical activity, warm or hot environmental conditions, lack of acclimatization, and wearing clothing that holds in body heat in addition to personal risk factors based on each individual's condition.
Hazardous heat exposure can occur indoors or outdoors, and can occur during any season if the conditions are right, not only during heat waves. The following is a list of some industries where workers have suffered heat-related illnesses.
OUTDOORS
Agriculture, Construction (especially road, roofing, and other outdoor work), Landscaping, Mining and Logging, Mail and Package Delivery, Oil and Gas Well Operations.
INDOORS
Bakeries, Kitchens, Laundries (heat-generating appliances), Electrical Utilities (especially boiler rooms), Fire Service, Iron and Steel Mills and Foundries, Manufacturing with hot local heat sources such as furnaces, and Warehousing.
It is mandatory to train both employers and employees regarding the dangers and safety measures to prevent Heat Illness, which includes Heat Exhaustion, Heat Stress, Heat Stroke, and even death. This poster was created by OSHA and can be used as a reference guide, and as a supplement to the required training. Displaying OSHA safety posters is a sign of your commitment to safety.
Both employers and employees who are exposed to heat in their workplaces need to be trained in the prevention of Heat Illness, which includes Heat Stress, Heat Exhaustion, Heat Stroke, and even death. This OSHA workplace poster is designed as a reference guide and a supplemental training tool. Measu...
