1. Heat Stress
I told you to bring water, you dummy! Turn the AC on.

2. Heat Stress

3. Heat Stress
Types of Heat Transfer
• Conduction.
• Convection.
• Radiation.
• Evaporation.

4. Heat Stress

5. Heat Stress
Convection

6. Heat Stress
Radiation

7. Heat Stress
Evaporation Cooling

8. Heat Stress
Normal Body Cooling
• The average 160 lb. adult has approx. 10 pints
(5 quarts) of blood and approx. 60,000 miles of
plumbing.
• When the body core temperature rises, blood is
pumped to the skin to dissipate heat.
• The skin is the largest organ of the body.
• Sweating increases (evap cooling).
• Heart rate increases to speed up the flow of
blood to the skin.

9. Heat Stress
• If everything is working correctly, the
excess heat will dissipate and the core
temp. will drop and stabilize.
• Primary cooling of the body is by radiation.
• Secondary is by evaporation (sweating).

10. Heat Stress
Types of Heat Related Stress
• Transient Heat Stress
• Heat Rash (Prickley Heat)
• Heat Cramps
• Heat Exhaustion
• Heat Stroke

11. Heat Stress
Acclamation

12. Heat Stress
Risk Factors Risk Factors
• Age- young children • Use of illegal drugs.
and the elderly. • Prescription meds.
• Over age 40. • Use of alcohol.
• Overweight or obese. • Caffeinated drinks.
• Poor physical • High blood pressure.
condition. • Kidney, liver problems
• Coronary problems. • Respiratory problems.

13. Heat Stress
Risk Factors
• Previous heat illness.
• Diabetes.
• Pregnancy.
• Fever.
• Sleep deprivation.
• Low salt diet.
• Poor diet

14. Heat Stress
FIRST AID
• Transient Heat Stress
a. Training and acclamation.
• Heat Rash (Prickly Heat)
a. Keep affected area clean, dry, use
medicated powder.

15. Heat Stress
FIRST AID
• Heat Cramps
Symptoms – Cramping of large muscles during
or after exertion.
First Aid:
a. Stop and rest in cool area.
b. Drink cool water or sports drink.

16. Heat Stress
First Aid
• Heat Exhaustion
Symptoms – Fatigue, weakness, dizziness, faint,
nausea, headache, cool moist skin, normal or
slightly elevated temperature, rapid pulse, pale
or flushed skin.
First Aid:
a. Move victim to cool area, rest, sip cool water
or sports drink, sponge or cool shower. Seek
medical assistance.

17. Heat Stress
First Aid
• Heat Stroke
Symptoms – Hot dry skin, skin is flushed, red or
bluish, confusion, rapid pulse, convulsions,
elevated temperature, unconsciousness. May be
fatal. May suffer permanent damage to brain,
heart, lungs, muscles, liver and/or kidneys.
First Aid:
CALL911 This is a medical emergency.
a. Remove victim to cool location.
b. Remove clothing, sponge, hose, immerse.
c. Do not give fluids, they won’t keep it down.

18. Heat Stress
• Once the body core is overheated, it takes a
minimum of 30 minutes to cool and stabilize.
• Heat is a stressor that increases strain,
accelerates fatigue and increases the possibility
of an accident.
• Heat stress is preventable through training.
• Approximately 29 people die from heat related
stress in Arizona every year.

19. Heat Stress
Water Intoxication
• Abnormally low concentration of sodium in the
blood.
• Drinking too much water.
• Symptoms the same as heat exhaustion and
heat stroke.
• Disrupts electrical signals in the brain and
nervous system.
• Can be fatal due to swelling of the brain.
• Mostly occurs in endurance athletes and
marathon runners.

20. Heat Stress
Questions????
It’s a dry heat, ya, right!