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Heat Stress Health Effects, Signs, & Symptoms


Also called Heat Syncope, is a temporary condition occurring in un-acclimated workers. Blood pools in the extremities rather than returning to the heart to be pumped to the brain. Workers usually recover after lying down briefly. After recovery, moving around will help prevent further fainting.

Heat Cramps

Temporary conditions characterized by painful muscle spasms of the arms, legs, or abdomen during or after work. Reversible with prompt treatment. Cramps are caused when a person sweats and drinks water, but does not replenish salts (electrolytes) lost in the sweat. Treatment consists of rest, drinking electrolyte fluids or water contain 1/4 tablespoon of table salt per quart, and removal from further heat exposure.

Heat Exhaustion or Heat Stress

Heat-induced illness that can cause serious injury. It occurs in workers who do not replace fluids and electrolytes lost through sweating. Symptoms include tiredness, weakness, thirst, and dizziness, with occasional headache, nausea, vomiting, diarrhea, and fainting. The skin is clammy and moist, complexion pale or flushed. Body temperature is normal or slightly high. Treatment includes rest, drinking balanced electrolyte fluids, and removal from further heat exposure. Employee should report to Occupational Medicine Clinic for observation and possible treatment.

Heat Stroke

Heat stroke may be fatal unless promptly and adequately treated. Caused by a failure of the body perspiration mechanism resulting in accelerating rise in body core temperature. Symptoms include confusion, loss of consciousness, convulsions and coma. The skin is hot and dry, temperature is 104-106° F, pulse is rapid, and blood pressure falls. Rapid cooling of the body should begin immediately (immerse in chilled water accompanied by vigorous massage of the skin, loosen clothing, move to shade, spray with cool water & fan). Call 2222 for emergency transport to hospital.

Pregnancy Complications

If during the first trimester of pregnancy, a female worker's core temperature exceeds 39C (102.2F) for extended periods, there is an increased risk of malformation to the unborn fetus.

Reproduction Complication

Core temperatures above 38C (100.4F) may be associated with temporary infertility in both males and females.

Heat Rash

Also known as prickly heat, occurs in hot, humid environments where sweat can not easily evaporate from the skin. A temporary, discomforting rash develops. Can be prevented and treated by resting in a cool place and regularly bathing and drying the skin.