Heat Stress is a serious concern in occupational health and safety. It is important we carry out more awareness on heat stress to reduce incidents relating to heat stress.

1. MANAGING HEAT STRESS
Developed By: Naveed Ahmed

2. MANAGING HEAT STRESS
Heat stress can be more than a minor inconvenience for those who work in
extremely warm conditions. Knowing how to prevent, identify and treat its
symptoms can literally save lives.
 Heat from the sun or work environment can create a
life threatening emergency.
 Heat stress occurs when the core body temperature
rises and cannot be cooled by sweating.
 Our bodies maintain a fairly constant internal
temperature even though exposed to varying
environmental temperatures.
 To keep internal body temperatures within safe limits in hot conditions, the
body gets rid of excess heat by evaporating sweat and varying the blood
flow to the skin. These responses are controlled by the brain and usually
occur when the blood exceeds 98.6º F.

3. The Body’s Response to Heat
 The body tries to maintain a constant internal
temperature
 When the internal temperature rises, the body
attempts to get rid of excess heat by:
 Increasing blood flow to skin surface
 Releasing sweat onto skin surface

4. Effects of Heat Stress On Your Body
 Skin rash
 Muscle cramps
 Exhaustion
 Fainting
 Heat Stroke - life threatening!

5. Effects of Body’s Response
 Reduced blood flow to brain
• Reduced mental alertness and
comprehension
 Reduced blood flow to active
muscles
• Fatigue, loss of strength
 Increased sweating
• Slipperiness
Potential result of = a Higher rate of mistakes/injuries
too much heat

6. External FactorsAffecting Heat Stress
 Humidity
 Radiant heat (hot equipment, vessels and
sun)
 Air movement
 Clothing
 Work rate (difficulty of work)
If these not controlled,
HEAT STRESS MAY OCCUR!

7.  High air temperature reduces
effectiveness of the cooling system
 High humidity reduces evaporation rate of
sweat
 Excess loss of sodium
 Dehydration (common)
When Cooling Mechanisms Fail

8. Heat Rash
Heat rash is the most common problem in hot work environments.
Symptoms
 Prickly heat shown as red bumps on
the skin; usually appears in areas
where the clothing is restrictive
 Sweat ducts plug; sweat cannot
freely evaporate from skin
Prevention
 Wear breathable clothing (e.g. cotton)
 Cleanse skin thoroughly
Treatment
 Keep skin dry
 Apply calamine lotion
 Sleep in cool location

9. Heat Cramps
Cramps may result after excessive sweating and dehydration.
Symptoms
 Shriveled skin, sunken eyes, dry mouth / tongue
 Severe pain and cramps in legs and abdomen
 Weakness, dizziness or fainting
 Profuse sweating
 Headaches
Treatment
 Increase fluid / salt intake
 Drink at least 16 ounces of water per hour
 Rest and move to a cool place

10. Heat Exhaustion
Blood moves toward the outer body to remove heat. Blood pools in
the skin leaving less for the brain.
Symptoms
 Fatigue, headache, dizziness, profuse sweating, rapid
pulse, thirst, loss of appetite, nausea, vomiting and
fainting
Treatment
 Get to a shaded area and cool off; use cold wet towels
or ice and fan
 Drink lots of water; may need IV
 Loosen clothing and elevate legs above heart
 If condition worsens, seek medical attention
immediately
If left untreated, heat exhaustion can lead to HEAT STROKE!

11. Heat Stroke
A medical emergency and life-threatening condition caused byfailure
of heat-regulating mechanisms of the body due to high heat and
humidity. The body’s core temperature rises and stops sweating.
Symptoms
 Hot, red skin and NO sweating
 Rapid pulse, confusion and nausea
 Possible convulsions and unconsciousness
Treatment
 Move to a cooler location and loosen clothing
 Immerse in cool water or wrap in wet sheets
 Apply cold compresses to head, neck and groin
SEEK MEDICAL ATTENTION IMMEDIATELY!

12. Dehydration
SEEK MEDICAL ATTENTION IMMEDIATELY!
 Cause:
 Excessive fluid loss
 Signs & symptoms:
 Fatigue, weakness, dry mouth
 Treatment:
 Fluids and salt replacement

13. Work-related Factors
 Workload
 Type of work
 Level of physical activity
 Time spent working
 Clothing
 Weight (heavy v. breathable)
 Color (dark v. light)
 Personal protective equipment
and clothing

14. Personal Factors
 Age
 Weight/fitness
 Use of drugs, alcohol, caffeine,
medication
 Prior heat-related illness

15. Prevention
 Drink lots of water (at least 16 ounces per hour),
even if not thirsty
 Start drinking water before you start work
 Avoid beverages containing alcohol or caffeine
 Get used to the heat for short periods, followed by
longer periods of work
 Alternate work and rest breaks, with longer breaks
in cooler areas
 Work in teams to limit strenuous activity

16. Prevention (cont.)
 Ensure adequate ventilation
 Wear lightweight, loose-fitting, light-colored
clothing (e.g. cotton)
 Notify your Supervisor at first sign of any problem
 Keep an eye on your coworkers. Use a buddy
system.
 Check your urine color for signs of dehydration

17. WARNING!
 In the course of a day's work in the heat,
you could sweat as much as 2-3 gallons.
 Drink an adequate amount of water,
even when you are not thirsty.
 You should drink 16 ounces of fluids
every hour to replenish the necessary
fluids in the body.
 By the time you feel thirsty, you are
already 10% dehydrated.
 Urine color gives indication of hydration
state (i.e. if urine is dark, drink more
water).

18. What to Do When a Worker is ill from Heat
 Call a First Responder / Supervisor for help. If they
are not available, call 300 / 400
 Have someone stay with the worker until help
arrives
 Move the worker to a cooler / shaded area
 Remove outer clothing
 Fan and mist the worker with water; apply ice (ice
bags or ice towels)
 Provide cool drinking water, if able to drink
IF THE WORKER IS NOT ALERT or seems confused, this may be a heat
stroke. CALL MEDICAL EMERGENCY IMMEDIATELY and apply ice as
soon as possible!

19. Quiz
Circle the best answer to each statement.
1. In the courseof aday’s work in heat, aperson cansweat asmuch as2-3 gallons. True or False
2. Heat stress occurs when the core body temperature rises and cannot be cooled by sweating. True
or False
3. Humidity is not an external factor associated with heat stress. True or False
4. Heat rash occurs when sweat ducts plug and sweat cannot freely evaporate from the skin. True or
False
5. Heat cramps are treated by drinking 16 ounces of water every 4 hours. True or False
6. Headaches and dizziness are not symptoms of heat exhaustion. True or False
7. Hot, red skin and no sweating are symptoms of heat stroke. True or False
8. If someone is having a heat stroke, seek medical attention immediately. True or False
9. Applying ice is not recommended for treating someone taken ill from the heat. True or False
10. If you are not thirsty, you must be well-hydrated. True or False
11. Drinking beverages with caffeine is a good way to prevent dehydration. True or False
12. Darker urine color is an indicator of dehydration. True or False