Heat Stress Safety

Beat the Heat: Identifying and Preventing Heat Stress

ST. PAUL, Minn. — Now that summer is in full swing, heat stress can be a major concern in workplace environments. It can potentially cause irritability, low morale, absenteeism, shortcuts in procedures and unsafe behavior according to NIOSH (National Institute for Occupational Safety and Health). In severe cases, heat stress, in the form of heat stroke and exertional heat stress, can be extremely serious.

Excessive exposure to heat can seriously impact worker health and safety. A written and effective heat stress policy is key in helping to reduce heat stress issues in the workplace. This includes things such as accurate measurement of environmental conditions, implementing an effective hydration program, and establishing work-rest cycles. Do you know what you need to help stay safe?

What are the Heat Stress Warning Signs?

Heat Stress Perspiring Man

First, you need to be able to identify heat stress and when someone is in distress. If the body cannot get rid of excess heat, it will store it. When this happens, the body’s core temperature rises and the heart rate increases. According to the Centers for Disease Control (CDC), there are many symptoms of heat exhaustion such as:

  • Headaches, dizziness, lightheadedness or fainting
  • Weakness
  • Moist skin
  • Mood changes such as irritability or confusion
  • Upset stomach or vomiting
  • Dry, hot skin with no sweating
  • Mental confusion or losing consciousness
  • Seizures or convulsions

As the body continues to store heat, the person begins to lose concentration and has difficulty focusing on a task, may become irritable or sick, and often loses the desire to drink. The next stage is most often fainting and even death if the person is not cooled down.

How Do You Know If it is Too Hot?

According to U.S. Occupational Safety and Health Administration (OSHA), the main factors leading to heat stress include strenuous physical activity, high air temperature, high humidity, direct contact with hot materials, acclimation, clothing choices, work duration, and radiant heat sources. Total heat load on a body is the combination of environmental conditions, clothing and metabolic or workload factors. Construction workers and others like utility workers and agricultural workers who often spend all day outside should be especially cautious.

How Can Heat-Related Illness Be Prevented?

Heat-related illnesses can be prevented according to OSHA. According to the EHS Daily Advisor, important ways to reduce heat exposure and the risk of heat-related illness include engineering controls, such as air conditioning and ventilation, that make the work environment cooler, and work practices such as work/rest cycles, drinking water often, and providing an opportunity for workers to build up a level of tolerance to working in the heat. Check out this OSHA Quick Card about heat stress to help remind employees about symptoms, prevention and treatment.

Heat stress monitors can help evaluate the work environment and should be used if heat stress is a constant concern on your worksite. To learn more about the solutions available to help you prevent heat stress and other workplace hazards, please check out this short webinar and we encourage you to speak with our knowledgeable safety specialists today.


Check out the National Integrated Heat Health Information System, compiled by multiple federal agencies, for forecasts, resources for outdoor workers and many other valuable web pages, guidelines and other assets.

Publisher’s Note: This post was originally published on July 6, 2017 but has since been updated with additional content and resources, including in July of 2020 and 2021.