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Hazards - Heat Wave

A National Problem 
Heat kills by taxing the human body beyond its abilities. In a normal year, about 175 Americans succumb to the demands of summer heat. Among the large continental family of natural hazards, only the cold of winter -- not lightning, hurricanes, tornadoes, floods, or earthquakes -- takes a greater toll. In the 40-year period from 1936 through 1975, nearly 20,000 people were killed in the United States by the effects of heat and solar radiation. In the disastrous heat wave of 1980, more than 1,250 people died.

Monitor Those at High Risk

Heat Wave Safety Tips 
Those at greatest risk of heat-related illness include:
  • infants and children up to four years of age
  • people 65 years of age or older
  • people who are overweight
  • people who overexert during work or exercise
  • people who are ill or on certain medications

Heat Related Links


Preparedness and Prevention


NEVER LEAVE CHILDREN OR PETS IN A PARKED CAR: The temperature can raise to 135 degrees in less than ten minutes, which can cause death to children or pets. If you see a child or pet left unattended in a parked car, you should call 9-1-1 and alert authorities.

Slow down.  Strenuous activities should be reduced, eliminated, or rescheduled to the coolest time of the day.  Individuals at risk should stay in the coolest available place, not necessarily indoors.  

Dress for summer.  Lightweight, light-colored clothing reflects heat and sunlight, and helps your body maintain normal temperatures.  

Put less fuel on your inner fires. Foods (like proteins) that increase metabolic heat production also increase water loss.  

Drink plenty of water or other nonalcoholic fluids.  Your body needs water to keep cool. Drink plenty of fluids even if you don't feel thirsty. Persons who (1) have epilepsy or heart, kidney, or liver disease, (2) are on fluid restrictive diets, or (3) have a problem with fluid retention should consult a physician before increasing their consumption of fluids.  

Do not drink alcoholic beverages.  

Do not take salt tablets unless specified by a physician.  Persons on salt restrictive diets should consult a physician before increasing their salt intake.  

Spend more time in air-conditioned places. Air conditioning in homes and other buildings markedly reduces danger from the heat. If you cannot afford an air conditioner, spending some time each day (during hot weather) in an air conditioned environment affords some protection.  

Don't get too much sun.  Sunburn makes the job of heat dissipation that much more difficult.

Heat Disorders

Heat DisorderSymptomsFirst Aid
SunburnSkin redness and pain, possible swelling, blisters, fever, headaches.Take a shower, using soap, to remove oils that may block pores preventing the body from cooling naturally. If blisters occur, apply dry, sterile dressings and get medical attention.
Heat CrampsPainful spasms usually in leg and abdominal muscles. Heavy sweating.Firm pressure on cramping muscles or gentle massage to relieve spasm. Give sips of water. If nausea occurs, discontinue.
Heat ExhaustionHeavy sweating, weakness, skin cold, pale and clammy. Weak pulse. Normal temperature possible. Fainting, vomiting.Get victim to lie down in a cool place. Loosen clothing. Apply cool, wet cloths. Fan or move victim to air-conditioned place. Give sips of water. If nausea occurs, discontinue. If vomiting occurs, seek immediate medical attention.
Heat Stroke
(Sun Stroke)
High body temperature (106+). Hot, dry skin. Rapid, strong pulse. Possible unconsciousness. Victim will likely not sweat.Heat stroke is a severe medical emergency. Call 9-1-1 or emergency medical services or get the victim to a hospital immediately. Delay can be fatal. Move victim to a cooler environment. Try a cool bath or sponging to reduce body temperature. Use extreme caution. Remove clothing. Use fans and/or air conditioners. DO NOT GIVE FLUIDS.
Frequently Asked Questions for Extreme Heat
  1. What happens to the body as a result of exposure to extreme heat? 

    People suffer heat-related illness when the body’s temperature control system is overloaded. The body normally cools itself by sweating. But under some conditions, sweating just isn’t enough. In such cases, a person’s body temperature rises rapidly. Very high body temperatures may damage the brain or other vital organs. Several factors affect the body’s ability to cool itself during extremely hot weather. When the humidity is high, sweat will not evaporate as quickly, preventing the body from releasing heat quickly. Other conditions that can limit the ability to regulate temperature include old age, youth (age 0-4), obesity, fever, dehydration, heart disease, mental illness, poor circulation, sunburn, and prescription drug use and alcohol use.
  2. Who is at greatest risk for heat-related illness? 

    Those at greatest risk for heat-related illness include infants and children up to four years of age, people 65 years of age and older, people who are overweight, and people who are ill or on certain medications. 
  3. What is heat stroke? 
    Heat stroke is the most serious heat-related illness. It occurs when the body becomes unable to control its temperature: the body’s temperature rises rapidly, the sweating mechanism fails, and the body is unable to cool down. Body temperature may rise to 106°F or higher within 10 to 15 minutes. Heat stroke can cause death or permanent disability if emergency treatment is not provided. 
  4. What are the warning signs of a heat stroke?

    Warning signs of heat stroke vary but may include the following:
  • An extremely high body temperature (above 103°F)
  • Red, hot, and dry skin (no sweating)
  • Rapid, strong pulse
  • Throbbing headache
  • Dizziness
  • Nausea
  • Confusion
  • Unconsciousness
  1. What should I do if I see someone with any of the warning signs of heat stroke? 

    If you see any of these signs, you may be dealing with a life-threatening emergency. Have someone call for immediate medical assistance while you begin cooling the victim. Do the following:
  • Get the victim to a shady area.
  • Cool the victim rapidly, using whatever methods you can. For example, immerse the victim in a tub of cool water; place the person in a cool shower; spray the victim with cool water from a garden hose; sponge the person with cool water; or if the humidity is low, wrap the victim in a cool, wet sheet and fan him or her vigorously. 
  • Monitor body temperature and continue cooling efforts until the body temperature drops to 101-102°F.
  • If emergency medical personnel are delayed, call the hospital emergency room for further instructions.
  • Do not give the victim alcohol to drink.
  • Get medical assistance as soon as possible.

  1. What is heat exhaustion? 

    Heat exhaustion is a milder form of heat-related illness that can develop after several days of exposure to high temperatures and inadequate or unbalanced replacement of fluids. Those most prone to heat exhaustion are elderly people, those with high blood pressure, and those working or exercising in a hot environment. 
  2. What are the warning signs of heat exhaustion? 

    The warning signs of heat exhaustion include the following:
  • Heavy sweating
  • Paleness
  • Muscle cramps
  • Tiredness
  • Weakness
  • Dizziness
  • Headache 
  • Nausea or vomiting
  • Fainting

The skin may be cool and moist. The pulse rate will be fast and weak, and breathing will be fast and shallow. If heat exhaustion is untreated, it may progress to heat stroke. See medical attention if symptoms worsen or last longer than one hour.

  1. What steps can be taken to cool the body during heat exhaustion? 
  • Drink cool, nonalcoholic beverages.
  • Rest.
  • Take a cool shower, bath, or sponge bath.
  • Seek an air-conditioned environment.
  • Wear lightweight clothing.
  1. What are heat cramps and who is affected? 
    Heat cramps are muscle pains or spasms – usually in the abdomen, arms, or legs – that may occur in association with strenuous activity. People who sweat a lot during strenuous activity are prone to heat cramps. This sweating depletes the body’s salt and moisture. The low salt level in the muscles causes painful cramps. Heat cramps may also be a symptom of heat exhaustion. If you have heart problems or are on a low-sodium diet, seek medical attention for heat cramps. 
  2. What should I do if I have heat cramps? 
    If medical attention is not necessary, take the following steps:
  • Stop all activity and sit quietly in a cool place.
  • Drink clear juice or a sports beverage.
  • Do not return to strenuous activity for a few hours after the cramps subside because further exertion may lead to heat exhaustion or heat stroke.
  • Seek medical attention for heat cramps if they do not subside in 1 hour.

  1. What is heat rash? 

    Heat rash is a skin irritation caused by excessive sweating during hot, humid weather. It can occur at any age but is most common in young children. Heat rash looks like a red cluster of pimples or small blisters. It is more likely to occur on the neck and upper chest, in the groin, under the breasts, and in elbow creases.
  2. What is the best treatment for heat rash? 

    The best treatment for heat rash is to provide a cooler, less humid environment. Keep the affected area dry. Dusting powder may be used to increase comfort, but avoid using ointments or creams -- they keep the skin warm and moist and may make the condition worse. 
  3. Can medications increase the risk of heat-related illness? 

    The risk for heat-related illness and death may increase among people using the following drugs: (1) psychotropics, which affect psychic function, behavior, or experience (e.g. haloperidol or chlorpromazine); (2) medications for Parkinson’s disease, because they can inhibit perspiration; and (3) tranquilizers such as phenothiazines, butyrophenones, and thiozanthenes.
  4. How effective are electric fans in preventing heat-related illness? 
    Electric fans may provide comfort, but when the temperature is in the high 90s, fans will not prevent heat-related illness. Taking a cool shower or bath or moving to an air-conditioned place is a much better way to cool off. Air conditioning is the strongest protective factor against heat-related illness. Exposure to air conditioning for even a few hours a day will reduce the risk for heat-related illness. Consider visiting a shopping mall or public library for a few hours. 
  5. How can people protect their health when temperatures are extremely high?

    Remember to keep cool and use common sense. Drink plenty of fluid, replace salts and minerals, wear appropriate clothing and sunscreen, pace yourself, stay cool indoors, schedule outdoor activities carefully, use a buddy system, monitor those at risk, and adjust to the environment.
  6. How much should I drink during hot weather? 

    During hot weather you will need to drink more liquid than your thirst indicates. Increase your fluid intake, regardless of your activity level. During heavy exercise in a hot environment, drink two to four glasses (16-32 ounces) of cool fluids each hour. Avoid drinks containing alcohol because they will actually cause you to lose more fluid.
  7. Should I take salt tablets during hot weather? 

    Do not take salt tablets unless directed by your doctor. Heavy sweating removes salt and minerals from the body. These are necessary for your body and must be replaced. The easiest and safest way to do this is through your diet. Drink fruit juice or a sports beverage when you exercise or work in the heat.
  8. What is the best clothing for hot weather or a heat wave? 
    Wear as little clothing as possible when you are at home. Choose lightweight, light-colored, loose-fitting clothing. In the hot sun, a wide-brimmed hat will provide shade and keep the head cool. If you must go outdoors, be sure to apply sunscreen 30 minutes prior to going out and continue to reapply according to the package directions. Sunburn affects your body’s ability to cool itself and causes a loss of body fluids. It also causes pain and damages the skin.
  9. What should I do if I work in a hot environment? 
    Pace yourself. If you are not accustomed to working or exercising in a hot environment, start slowly and pick up the pace gradually. If exertion in the heat makes your heart pound and leaves you gasping for breath, STOP all activity. Get into a cool area or at least in the shade, and rest, especially if you become lightheaded, confused, weak, or faint.

Tips on Preventing and Managing Heat

The best defense is prevention.  Here are some prevention tips:

  • Drink more fluids (nonalcoholic), regardless of your activity level.  Don’t wait until you’re thirsty to drink.  Warning: If your doctor generally limits the amount of fluid you drink or has you on water pills, ask the doctor how much you should drink while the weather is hot.
  • Don’t drink liquids that contain caffeine, alcohol, or large amounts of sugar–these actually cause you to lose more body fluid.  Also avoid very cold drinks, because these can cause stomach cramps.
  • Stay indoors and, if at all possible, stay in an air-conditioned place.  If your home does not have air conditioning, go to the shopping mall or public library–even a few hours spent in air conditioning can help your body stay cooler when you go back into the heat.  Call your local health department to see if there are any heat-relief shelters in your area.
  • Electric fans may provide comfort, but when the temperature is in the high 90s, fans will not prevent heat-related illness.  Taking a cool shower or bath, or moving to an air-conditioned place is a much better way to cool off.
  • Wear lightweight, light-colored, loose-fitting clothing.
  • NEVER leave anyone in a closed, parked vehicle.
  • Although any one at any time can suffer from heat-related illness, some people are at greater risk than others.  Check regularly on: 
    • Infants and children up to 4 years of age.
    • People aged 65 or older.
    • People who have a mental illness.
    • Those who are physically ill, especially with heart disease or high blood pressure.
  • Visit adults at risk at least twice a day and closely watch them for signs of heat exhaustion or heat stroke. Infants and young children, of course, need much more frequent watching.


Heat Wave Graphic

Forecast Products

Heat Index Chart heatin~1.gif (63709 bytes)
Click on image

If you must be out in the heat:

  • Try to be outdoors before noon or in the evening.
  • Cut down on exercise.  If you must exercise, drink two to four glasses of cool, nonalcoholic fluids each hour.  A sports beverage can replace the salt and minerals you lose in sweat.  Warning: If you are on a low-salt diet, talk with your doctor before drinking a sports beverage.  Remember the warning in the first “tip” (above), too.  
  • Try to rest often in shady areas. 
  • Protect yourself from the sun by wearing a wide-brimmed hat (also keeps you cooler) and sunglasses and by putting on sunscreen of SPF 15 or higher (the most effective products say “broad spectrum” or “UVA/UVB protection” on their labels).



de to beating the Heat 

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