Ensure adequate ventilation or air-conditioning during heat waves, particularly for people who are very old or very young.

Avoid leaving children in automobiles in hot weather, particularly with closed windows.

Avoid strenuous exertion in hot environments and poorly ventilated spaces.

Avoid inappropriately heavy, insulated clothing.

If exertion in heat is unavoidable, wear loose-fitting clothing made from fabrics that breathe, take frequent breaks, use a fan, and drink every few hours regardless of thirst.

If 2% or more of body weight is lost during exercise or work, drink extra fluids.

If 4% or more of body weight is lost during exercise or work, limit activity for 1 day.

If large amounts of water are drunk, consume salts in fluids or food.

If prolonged exertion in heat is unavoidable, starting 10 to 14 days before maximum exertion is required, begin with moderate activity done for about 15 minutes a day, slowly increasing the intensity of the activity and the time spent doing it.