High temperatures and high humidity raise the risk of heat exhaustion and, worse, heat stroke, especially across the South, Southwest and Midwest regions of North America during the summer work season.

As the temperature rises, human bodies cool themselves by perspiring. Heat is removed from the body as liquids move to the surface of the skin; evaporation removes perspiration so that more liquid can escape. When humidity is high, evaporation is more difficult, and the cooling process is impeded.

The key to the body’s successful cooling system is the steady infusion of water to replace the evaporating liquids. Without adequate hydration, body temperatures can rise precipitously to life-threatening levels.

The first stage of danger is heat exhaustion characterized by heavy sweating; slightly elevated body temperature; pale, clammy skin; headache, nausea or vomiting; and unusual weakness, dizziness or fainting.

Protect Against Heat Illness

  • Adjust work patterns to minimize strenuous outdoor activity during hottest hours.
  • Drink eight ounces of water every hour, even more if it’s very hot and you’re very active.
  • Check with your doctor to learn if any of your medications reduce your tolerance to heat or sunlight.
  • Avoid sudden changes in temperature; for instance, air out a hot car before entering.

The remedy is to get out of the sun and cool down. A victim should lie down and loosen clothing for ventilation; drink sips of cool water; sponge the forehead and body with cool water; and check body temperature and seek medical help if it’s above 102 degrees; and, if conditions persist beyond an hour, seek medical help regardless of body temperature.

If untreated, heat exhaustion can turn rapidly to heat stroke.

Heat stoke is characterized by confusion, unconsciousness or, possibly, seizure; body temperature above 102 degrees; rapid, shallow breathing and rapid pulse; and hot, dry, flushed skin, but usually no sweating.

If heat stroke is suspected, medical help should be sought immediately. It is necessary but not sufficient to get out of the sun and attempt to lower the body’s temperature through cool baths or drinking water. Medical attention is required. Heat stroke can be fatal.

[Steve Clark]