Heat Safety Awareness Day May 25, 2012

The Hazards of Excessive Heat

When the body heats too quickly to cool itself safely, or when you lose too much fluid or salt through dehydration or sweating, your body temperature rises and heat-related illness may develop. Heat disorders share one common feature: the individual has been in the heat too long or exercised too much for his or her age and physical condition.

Studies indicate that, other things being equal, the severity of heat disorders tends to increase with age. Conditions that cause heat cramps in a 17-year-old may result in heat exhaustion in someone 40 years old, and in heat stroke in a person over 60. Sunburn, with its ultraviolet radiation burns, can significantly retard the skin's ability to shed excess heat. Acclimatization has to do with adjusting sweat-salt concentrations, among other things. The idea is to lose enough water to regulate body temperature, with the least possible chemical disturbance--salt depletion.

The atmosphere and the windows of a car are relatively transparent to the sun’s shortwave radiation (yellow in figure below) and are warmed little. This shortwave energy, however, does heat objects it strikes. For example, a dark dashboard or seat can easily reach temperatures in the range of 180°F to more than 200°F. These objects, e.g., dashboard, steering wheel, childseat, heat the adjacent air by conduction and convection and give off longwave radiation (infrared), which efficiently warms the air trapped inside a vehicle.

Heat Safety

Child Safety Tips

• Make sure your child's safety seat and safety belt buckles aren't too hot before securing your child in a safety restraint system, especially when your car has been parked in the heat.
• Never leave your child unattended in a vehicle, even with the windows down.
• Teach children not to play in, on, or around cars.
• Always lock car doors and trunks--even at home--and keep keys out of children's reach.
• Always make sure all children have left the car when you reach your destination. Don't leave sleeping infants in the car ever!

Adult Heat Wave Safety Tips

• Slow down. Reduce, eliminate or reschedule strenuous activities until the coolest time of the day. Children, seniors and anyone with health problems should stay in the coolest available place, not necessarily indoors.
• Dress for summer. Wear lightweight, light-colored clothing to reflect heat and sunlight.
• Put less fuel on your inner fires. Foods, like meat and other proteins that increase metabolic heat production also increase water loss.
• Drink plenty of water, non-alcoholic and decaffeinated fluids. Your body needs water to keep cool. Drink plenty of fluids even if you don't feel thirsty. Persons who have epilepsy or heart, kidney or liver disease, are on fluid restrictive diets or have a problem with fluid retention should consult a physician before increasing their consumption of fluids. Do not drink alcoholic beverages and limit caffeinated beverages.
• During excessive heat periods, 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, go to a library, store or other location with air conditioning for part of the day.
• Don't get too much sun. Sunburn reduces your body's ability to dissipate heat.
• Do not take salt tablets unless specified by a physician.

Heat Disorder Symptoms

SUNBURN: Redness and pain. In severe cases swelling of skin, blisters, fever, headaches. First Aid: Ointments for mild cases if blisters appear and do not break. If breaking occurs, apply dry sterile dressing. Serious, extensive cases should be seen by physician.

HEAT CRAMPS: Painful spasms usually in the muscles of legs and abdomen with heavy sweating. First Aid: Firm pressure on cramping muscles or gentle massage to relieve spasm. Give sips of water. If nausea occurs, discontinue water.

HEAT EXHAUSTION: Heavy sweating; weakness; cold, pale, clammy skin; thready pulse; fainting and vomiting but may have normal temperature. First Aid: Get victim out of sun. Once inside, the person should lay down and loosen his or her clothing. Apply cool, wet cloths. Fan or move victim to air conditioned room. Offer sips of water. If nausea occurs, discontinue water. If vomiting continues, seek immediate medical attention.

HEAT STROKE (or sunstroke): High body temperature (106° F or higher), hot dry skin, rapid and strong pulse, possible unconsciousness. First Aid: HEAT STROKE IS A SEVERE MEDICAL EMERGENCY. SUMMON EMERGENCY MEDICAL ASSISTANCE OR GET THE VICTIM TO A HOSPITAL IMMEDIATELY. DELAY CAN BE FATAL. While waiting for emergency assistance, move the victim to a cooler environment reduce body temperature with cold bath or sponging. Use extreme caution. Remove clothing, use fans and air conditioners. If temperature rises again, repeat process. Do NOT give fluids. Persons on salt restrictive diets should consult a physician before increasing their salt intake.

Heat Stress in the Elderly

Elderly people (that is, people aged 65 years and older) are more prone to heat stress than younger people for several reasons:

• Elderly people do not adjust as well as young people to sudden changes in temperature.
• They are more likely to have a chronic medical condition that changes normal body responses to heat.
• They are more likely to take prescription medicines that impair the body's ability to regulate its temperature or that inhibit perspiration.

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 body loses its ability to sweat, and it is unable to cool down. Body temperatures 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.

Signs and Symptoms of Heat Stroke

Warning signs 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

For more information about Heat Safety contact the National Weather Service or request the Excessive Heat Events Guidebook.