What Is Heat Stress?

Working muscles need a greater blood flow to cool the body. The body needs to shift blood away from muscles to assure an ideal sweat rate and to cool the blood. Dehydration can cause low blood volume, which can lower the body’s ability to cool the blood, leading to confusion, fatigue and potentially, heat illness.

Dry Clothes and Skin Don’t Mean You Aren’t Sweating!

You may not feel wet or sticky in dryer climates, but you are still sweating. You can lose as much as 68 ounces (half a gallon) of fluid on a very warm day. Fainting (heat syncope) may be a problem for workers who simply stand still in the heat when they are not acclimated to a hot environment. Victims usually recover quickly after lying down for a brief period. Moving around, rather than standing still, usually reduces the possibility of fainting.

Symptoms of Heat Exhaustion

  • Headaches, dizziness, lightheadedness 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.

Ways to Prevent Heat Stress

  • Hydrating before work activity is crucial. Consume water or an electrolyte beverage 24 hours prior to activity.
  • Drink 16 ounces of water two-three hours before work activity.
  • Drink water frequently (every 15-30 minutes, drink six-12 ounces)
  • Most people consume enough salt in their diets. Salt tablets are NOT necessary for general use.
  • Post work activity – drink 16 ounces of water for every pound of weight loss.
  • Take breaks and move a person showing symptoms of heat stress away from heat sources or direct sunlight.
  • Utilize ventilation or fans in enclosed areas.
  • It takes one-two weeks for the body to adjust to higher temperatures. This adaptation to heat can be quickly lost, so your body will have to adjust after a vacation.
  • Avoid caffeine (makes the body lose water and increases the risk for heat illness).
  • Avoid alcohol consumption. Many cases of heat stroke have occurred the day after heavy drinking.
  • Wear light-colored, cotton clothes, and keep your shirt on.

What to Do for Heat-Related Illness

  1. Call 911 at once if a worker exhibits heat stroke symptoms.
  2. Move the worker to a cool, shaded area.
  3. Loosen or remove heavy clothing.
  4. Provide cool drinking water.
  5. Fan and mist the person with water.

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