Heat Stress

Dehydration occurs when the loss of body fluids exceeds the amount that is taken in. With dehydration, more water is moving out of our cells and bodies than what we take in through drinking. Along with the water, small amounts of electrolytes are also lost. When we lose too much water, our bodies may become out of balance or dehydrated.

Operations involving high air temperatures, radiant heat sources, high humidity, direct physical contact with hot objects, or strenuous physical activities have a high potential for inducing heat stress.

Preventing Heat Stress

  • Know signs/symptoms of heat-related illnesses; monitor yourself and coworkers.
  • Start work earlier in the day when the temperature is cooler.
  • Block out direct sun or other heat sources.
  • Use cooling fans/air conditioning and rest regularly.
  • Drink lots of water: about 1 cup every 15 minutes.
  • Wear lightweight, light colored, loose-fitting clothes.
  • Avoid alcohol, caffeinated drinks, or heavy meals. 

Symptoms of Heat Exhaustion

  • Headaches, dizziness, light-headedness or fainting.
  • Weakness and moist skin.
  • Mood changes such as irritability or confusion.
  • Upset stomach or vomiting.

Symptoms of Heat Stroke

  • Dry, hot skin with no sweating.
  • Mental confusion or losing consciousness.
  • Seizures or convulsions. 

What to Do for Heat-Related Illness

  • Move the worker to a cool, shaded area.
  • Loosen or remove heavy clothing.
  • Fan and mist them with cool water.
  • Offer sips of water if the victim is conscious.
  • Call 911

Take Heat Stress seriously!

Working in a hot environment puts stress on the body’s cooling system. When heat is combined with other stresses like hard physical work, loss of fluids, or fatigue it may lead to heat-related illness, disability, or even death.


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