Thermo Stress

1
Thermo Stress

• Lawrence S. Wong, CIH
• University of California Office of the President

2
Cold Stress
3
Cold Environment

• Bodys Energy Used to Keep Internal Temperature
  Warm
• Shift Blood Flow From Extremities/Outer Skin to
  Body Core (Chest Abdomen)
• Results in Rapid Cooling of Extremities and
  Exposed Skin
• Increases Chance for
• Hypothermia
• Frostbite
• Trench Foot

4
Wind Speed

• 16 k/hr (10 mph)
• Light Flag Fully Extended
• 24 k/hr (15 mph)
• Raises Newspaper Sheet Off the Ground
• 32 k/hr (20 mph)
• Wind Capable of Blowing Snow

5
Hypothermia - Means Low Heat

• Body Heat Lost Faster than Replaced
• Onset Body Core Temperature Drops 95OF
• Symptoms Pale Cold Skin
• Shiver, Stomp Feet, Lose Coordination, Slurred
  Speech, Fumble Items with Hands
• Body Temperature Continues to Fall
• Symptoms Worsen, Shivering Stops, Unable to Walk
  or Stand
• Body Temperature of 85OF - Unconscious
• Body Temperature of 78OF Death Could Occur

6
Hypothermia Treatment

• Mild Hypothermia
• Move to Warm Area Stay Active
• Remove Wet Clothes Replace with Dry Clothes or
  Blanket Cover the Head
• Drink Warm (Not Hot) Sugary Drink
• Avoid Drinks with Caffeine
• More Severe Hypothermia Do All Above and
• Contact EMS
• Cover All Extremities Completely Place Warm
  Objects on Head, Neck, Chest Groin
• Arms Legs Are Warmed Last

7
Severe Hypothermia Treatment

• Treat Victim Very Gently
• Do Not Apply External Heat to Re-Warm
• Hospital Treatment is Required

8
Frostbite

• Typically Affects Extremities Feet Hands
• Skin Freezes and Loses Water
• Usually Occurs at Temperatures lt 30OF
• Affected Body Part Cold, Tingling, Stringing or
  Aching, Followed by Numbness
• Skin
• Color Red, Then Purple, Then White
• Cold to the Touch
• Severe Cases - Blisters

9
Frostbite Treatment

• Do Not Rub Affected Area to Warm It
• Wrap Area in Soft Cloth
• Move to Warm Area Contact Medical Personnel
• Do Not Pour Water on Affected Part
• If Affected Part May Get Cold Again Do Not Warm
• Warming Re-Cooling Cause Severe Tissue Damage

10
Trench Foot

• Feet Immersed in Cold Water at Temperatures Above
  Freezing for Long Periods of Time
• Similar to Frostbite, But Not as Severe
• Symptoms Tingling, Itching, or Burning
  Sensation. Blisters May Be Present
• Soak Feet in Warm Water Then Wrap with Dry
  Cloth Bandages
• Drink Warm Sugary Drinks

11
Cold Stress Prevention

• Plan for Work in Cold Weather
• Wear Appropriate Clothing 3 Layers
• Outer Layer Gortex or Nylon Break the Wind
  Allow Some Ventilation
• Middle Layer Down or Wool Absorb Sweat
  Provide Insulation Even When Wet
• Inner Layer Cotton or Synthetic Weave To
  Allow Ventilation
• Layering Creates Air Pockets Helps Retain Body
  Heat

12
Cold Stress Prevention

• Wear Hat Exposed Head
• Up to 40 Loss of Body Heat
• Insulated Boots or Footwear
• Wear One Thick or Two Thin Pairs of Socks
• Too Many Socks Tighten Fit Restrict Blood Flow
• Hands Loose Dexterity lt 59OF
• Change of Dry ClothingIf Clothes Gets Wet
• Do Not Wear Tight Clothing Loose Air Pocket
  Insulation

13
Cold Stress Prevention

• Avoid Alcohol and Caffeine
• Increases Heat Loss Through Vasodilation
• Take Breaks Out of the Cold
• Schedule Work During Warmer Parts of Day
• Older Workers or Certain Medical Conditions
• May Be More Susceptible
• Radiant Heater
• Shielding Work Areas from Drafts Wind to Reduce
  Wind Chill

14
Cold Stress Training

• Proper Clothing Equipment
• Safe Work Practices
• Guidelines for Eating Drinking
• Risk Factors That Increase Health Effects of Cold
  Exposure
• How to Recognize Signs Symptoms of Hypothermia,
  Frostbite, Trench Foot
• Appropriate First Aid Treatment, Including
  Warming Procedures

15
Heat Stress
16
Heat Stress

• Body Produces/Stores More Heat Than You Lose
• Metabolism/Exercise
• Heat Absorbed
• Radiant Energy (Sun, Fire)
• Conductive (Direct Contact)
• Primary Heat Loss Evaporation
• Sweat/Evaporation
• Function of Humidity Temperature

17
Heat Illnesses

• Heat Rash
• Clogged/Irritated Sweat Glands
• Heat Cramps
• Painful Muscle SpasmsElectrolyte Imbalance
• Heat Exhaustion
• Heavy Sweating/Pale Clammy Skin
• Normal Heart Rate/Body Temperature
• Exert ional Heat Illness
• Stuporous Appearance, Nausea, High Temperature,
  Headache

18
Heat Illnesses

• Heat Stroke
• High Body Temperature
• Hot, Red (Gray) Dry Skin, Rapid Pulse
• Confusion, Loss of Consciousness
• Death is Imminent

• Heat Stroke First Aid
• Loosen Tight Clothing
• Cool with Wet Cloth
• If Conscious, Slowly Give 4 oz of Water Every 15
  Minutes
• Get Victim to Emergency Room ASAP

19
Heat Illness Prevention

• Drink Fluids
• Water 4 Cups (1 Quart/Hour)
• No Alcohol or Caffeine - Diuretics
• Eat
• Replace Electrolytes Lost by Perspiration

20
Heat Illness Prevention

• Acclimation
• Slow Process for Body to Condition Itself to Heat
• May Take Up to 10 Days
• Quickly Lost in a Matter of Days
• Conditioning/General Health
• Stay in Shape, Exercise Regularly
• Watch Your Weight

21
Cal/OSHA Heat Illness Regulation Title 8 Cal.
Code Regs., 3395

• Several Fatalities Due to Heat Stroke in
  California
• Construction
• Agriculture
• Became Permanent in April 22, 2006
• Essentially Identical to Emergency Regulation

22
Heat Illness Prevention Standard Application

• All Outdoor Places of Employment
• At Time When Environmental Factors for Heat
  Illness are Present
• Air Temperature
• Relative Humidity
• Radiant Heat, Conductive Heat
• Workload Severity/Duration
• Personal Protective Clothing/Equipment

23
(No Transcript)
24
Outdoor Environments

• Agriculture
• Construction
• Equipment and Storage Yard
• Loading Docks
• Tents
• Structures with One or More Open Sides
• Lack of Insulation/Heating From Sun
• Limited Air Circulation

25
Potable Drinking Water

• Sufficient Quantity at Beginning of Work Shift
• Can Begin Shift with Smaller Quantities if
  Effective Replenishment Procedures Developed and
  Implemented
• gt1 Quart/Employee/Hour for Entire Shift
• gt2 Gallons/Employee/8-Hour Shift
• Encourage Frequent Drinking of Water
• Thirst Unreliable Indicator of Dehydration

26
Access to Shade

• Available for Employee(s)
• Suffering from Heat Illness or
• Believe a Preventive Recovery Period is Needed
• At Least 5 Minutes
• Cool Down (Metabolic Heat/Heart Rate)
• Rehydrate
• Shade is
• Open to Air or
• Provided with Ventilation or Cooling for a Period
  of No Less Than 5 Minutes
• Access to Shade Permitted at All Times

27
Heat Illness Prevention Training

• Employee Training
• Supervisor Training
• Training Completed Prior to Assignment in Outdoor
  Environment with a Potential for Heat Illness

28
Employee Training

• Risk Factors for Heat Illness
• Environmental
• Personal
• Employers Preventive Procedures
• Importance of Water Consumption
• Importance of Acclimation

• Types/Signs Symptoms of Heat Illnesses
• Immediate Reporting Signs/Symptoms to Supervisor
• Employers Procedures Responding to Signs
  Symptoms
• Emergency Medical Procedures

29
Supervisor Training

• Same Information in Employee Training
• Procedures for Supervisor to Implement Heat
  Illness Prevention Program to Meeting Cal/OSHA
  Standard
• Procedures Supervisor to Follow
• When Employee Exhibits Symptoms of Possible Heat
  Illness and
• For Emergency Response