Heat Exhaustion & Heat-Induced Stress in the Workplace

Heat Exhaustion & Heat-Induced Stress in the Workplace

Heat Induced Stress is a condition when one's body is unable to adequately cool itself through perspiration.  The chances of experiencing heat-related illness depend on temperature, humidity and the work being performed.

Environmental Factors such as hot working conditions, humidity, and sun exposure will increase the probability for heat illness.

Personal Factors such as age, weight, and acclimation can also affect the severity of heat related illness. 

What You Eat & Drink plays an important role.  Alcohol, caffeine, and some prescription drugs can affect a person’s ability to cope with heat by causing dehydration.

The body cools itself by evaporation; trapping moisture against the body with heavy clothes reduces the rate of evaporation.  Many people working in industries that require flame resistant clothing are at an increased risk of experiencing heat stress due to outdoor exposure and working in buildings without air conditioning.  Also, layering may be necessary for hazard protection but can also reduce breathability which makes buying quality FR extra important.  FR fabrics that moisture wick will help spread and evaporate sweat quickly.

Heat Stress can cause cramps, excessive sweating, and fatigue, all of which increase the likelihood of a workplace accident.  If you are ever experiencing any of these symptoms, it’s best to remove yourself from any hazards to keep yourself and coworkers safe as well as seek assistance to safely recover. 

Heat Exhaustion is when the body is overactive in trying to control temperature, typically resulting in a loss of fluids and minerals. The cardiovascular system struggles to maintain adequate circulation because of a decrease in the volume of blood and loss of water and electrolytes.  Symptoms of heat exhaustion include headache, profuse sweating, dizziness, fatigue, nausea, and cool/clammy skin.

Heat Stroke can be life threatening.  This is when the body’s ability to regulate temperature fails and the body temperature rises to over 104 degrees Fahrenheit. The symptoms of heat stroke are irrational behavior, passing out, dehydration, weakness, high heart rate, low blood pressure, hyperventilation, vomiting, diarrhea. If you or your co-worker are experiencing these symptoms follow these steps:

  1. Get out of the heat
  2. Call 911
  3. Remove clothing and lie down
  4. Apply cool water or cool wet cloth (not ice)
  5. Get air moving

Additional Risk Factors

  • Hydration/electrolyte imbalance
  • Don’t trust “thirst”, it’s not a good indicator of your hydration level.
  • The US Military reported that only about 17% of soldiers suffering heat related illness were dehydrated.
  • Dark urine means you’re dehydrated.


  • Stay hydrated
  • Avoid alcohol, caffeine drinks
  • Light colored, light weight clothing that moisture wicks
  • Keep the sun off you, take breaks from direct sun exposure
  • Muscle contractions generate heat. If you start experiencing symptoms stop working.