Workers who are exposed to extreme heat or work in hot environments may be at risk of heat stress. Exposure to extreme heat can result in occupational illnesses and injuries. Heat stress can result in heat stroke, heat exhaustion, heat cramps, or heat rashes. Heat can also increase the risk of injuries in workers as it may result in sweaty palms, fogged-up safety glasses, and dizziness. Burns may also occur as a result of accidental contact with hot surfaces or steam.
Workers at risk of heat stress include outdoor workers and workers in hot environments such as firefighters, bakery workers, farmers, construction workers, miners, boiler room workers, factory workers, and others. Workers at greater risk of heat stress include those who are 65 years of age or older, are overweight, have heart disease or high blood pressure, or take medications that may be affected by extreme heat.
Prevention of heat stress in workers is important. Employers should provide training to workers so they understand what heat stress is, how it affects their health and safety, and how it can be prevented.
NIOSH Heat Stress Podcast
Heat stress can be a major concern for indoor and outdoor workers, especially during the hot summer months. Learn how to identify the symptoms and protect yourself from heat stress.
NIOSH Criteria for a Recommended Standard: Occupational Exposure to Heat and Hot Environments
Provides safety professionals and employers an evaluation of the scientific data on heat stress and hot environments, and NIOSH recommendations.
- Heat Related Illness Poster [PDF - 57 KB]
NIOSH Fast Facts: Protecting Yourself from Heat Stress
Print or order this free card for easy access to important safety information.
NIOSH Infographic: Protect your workers from Heat Stress
Learn some tips to protect workers including: acclimatization, rest breaks, and fluid recommendations.
NIOSH Workplace Solution: Preventing Heat-related Illness or Death of Outdoor Workers
Provides employers and safety professionals with information and case studies.
OSHA-NIOSH Infosheet: Protecting Workers from Heat Illness
Provides information to employers on measures they should take to prevent heat-related illnesses and death.
Now available in ePub format.
NIOSH Science Blog: Keeping Workers Hydrated and Cool Despite the Heat
Keeping workers cool and well-hydrated are the best ways to protect them when working in hot environments.
NIOSH Science Blog: Adjusting to Work in the Heat: Why Acclimatization Matters
The natural adaptation to the heat takes time, and from a management perspective, it may require careful planning.
MMWR: Heat Illness and Death Among Workers – United States, 2012-2013
This report describes findings from a review of Occupational Safety and Health Administration (OSHA) federal enforcement cases (i.e., inspections) resulting in citations.
MMWR: Heat-Related Deaths among Crop Workers, 1992-2006
This report describes a heat-related death and summarizes heat-related fatalities among crop production workers in the United States.
CDC: Extreme Heat
Additional information on heat-related illnesses and prevention.
- Page last reviewed: July 30, 2015
- Page last updated: July 19, 2016
- Content source:
- National Institute for Occupational Safety and Health Education and Information Division