Thermo StressThermo Stress

Lawrence S. Wong, CIHLawrence S. Wong, CIH

University of California Office of the University of California Office of the PresidentPresident

Cold StressCold Stress

Cold EnvironmentCold Environment►Body’s Energy Used to Keep Internal Body’s Energy Used to Keep Internal

Temperature WarmTemperature Warm Shift Blood Flow From Extremities/Outer Shift Blood Flow From Extremities/Outer

Skin to Body Core (Chest & Abdomen)Skin to Body Core (Chest & Abdomen) Results in Rapid Cooling of Extremities Results in Rapid Cooling of Extremities

and Exposed Skinand Exposed Skin► Increases Chance for:Increases Chance for:

HypothermiaHypothermia FrostbiteFrostbite Trench FootTrench Foot

Wind SpeedWind Speed►16 k/hr (10 mph)16 k/hr (10 mph)

Light Flag Fully Light Flag Fully ExtendedExtended

►24 k/hr (15 mph)24 k/hr (15 mph) Raises Newspaper Raises Newspaper

Sheet Off the Sheet Off the GroundGround

►32 k/hr (20 mph)32 k/hr (20 mph) Wind Capable of Wind Capable of

Blowing SnowBlowing Snow

Hypothermia - Means “Low Hypothermia - Means “Low Heat” Heat”

►Body Heat Lost Faster than ReplacedBody Heat Lost Faster than Replaced Onset – Body Core Temperature Drops – 95Onset – Body Core Temperature Drops – 95OOFF

►Symptoms – Pale & Cold SkinSymptoms – Pale & Cold Skin Shiver, Stomp Feet, Lose Coordination, Shiver, Stomp Feet, Lose Coordination,

Slurred Speech, Fumble Items with HandsSlurred Speech, Fumble Items with Hands►Body Temperature Continues to FallBody Temperature Continues to Fall

Symptoms Worsen, Shivering Stops, Unable Symptoms Worsen, Shivering Stops, Unable to Walk or Standto Walk or Stand

Body Temperature of 85Body Temperature of 85OOF - UnconsciousF - Unconscious Body Temperature of 78Body Temperature of 78OOF – Death Could F – Death Could

OccurOccur

Hypothermia TreatmentHypothermia Treatment►Mild HypothermiaMild Hypothermia

Move to Warm Area & Stay ActiveMove to Warm Area & Stay Active Remove Wet Clothes & Replace with Dry Remove Wet Clothes & Replace with Dry

Clothes or Blanket & Cover the HeadClothes or Blanket & Cover the Head Drink Warm (Not Hot) Sugary DrinkDrink Warm (Not Hot) Sugary Drink Avoid Drinks with CaffeineAvoid Drinks with Caffeine

►More Severe Hypothermia – Do All Above More Severe Hypothermia – Do All Above and:and: Contact EMSContact EMS Cover All Extremities Completely & Place Cover All Extremities Completely & Place

Warm Objects on Head, Neck, Chest & GroinWarm Objects on Head, Neck, Chest & Groin Arms & Legs Are Warmed LastArms & Legs Are Warmed Last

Severe Hypothermia Severe Hypothermia TreatmentTreatment

►Treat Victim Very GentlyTreat Victim Very Gently►Do Not Apply External Heat to Re-Do Not Apply External Heat to Re-

WarmWarm►Hospital Treatment is RequiredHospital Treatment is Required

FrostbiteFrostbite►Typically Affects Extremities – Feet & HandsTypically Affects Extremities – Feet & Hands►Skin Freezes and Loses WaterSkin Freezes and Loses Water►Usually Occurs at Temperatures Usually Occurs at Temperatures << 30 30OOFF►Affected Body Part – Cold, Tingling, Affected Body Part – Cold, Tingling,

Stringing or Aching, Followed by NumbnessStringing or Aching, Followed by Numbness►Skin Skin

Color – Red, Then Purple, Then WhiteColor – Red, Then Purple, Then White Cold to the TouchCold to the Touch Severe Cases - BlistersSevere Cases - Blisters

Frostbite TreatmentFrostbite Treatment►Do Not Rub Affected Area to Warm ItDo Not Rub Affected Area to Warm It►Wrap Area in Soft ClothWrap Area in Soft Cloth►Move to Warm Area & Contact Medical Move to Warm Area & Contact Medical

PersonnelPersonnel►Do Not Pour Water on Affected PartDo Not Pour Water on Affected Part► If Affected Part May Get Cold Again Do If Affected Part May Get Cold Again Do

Not WarmNot Warm Warming & Re-Cooling – Cause Severe Warming & Re-Cooling – Cause Severe

Tissue DamageTissue Damage

Trench FootTrench Foot►Feet Immersed in Cold Water at Feet Immersed in Cold Water at

Temperatures Above Freezing for Long Temperatures Above Freezing for Long Periods of TimePeriods of Time

►Similar to Frostbite, But Not as SevereSimilar to Frostbite, But Not as Severe►Symptoms – Tingling, Itching, or Symptoms – Tingling, Itching, or

Burning Sensation. Blisters May Be Burning Sensation. Blisters May Be PresentPresent

►Soak Feet in Warm Water & Then Soak Feet in Warm Water & Then Wrap with Dry Cloth BandagesWrap with Dry Cloth Bandages

►Drink Warm Sugary DrinksDrink Warm Sugary Drinks

Cold Stress PreventionCold Stress Prevention►Plan for Work in Cold WeatherPlan for Work in Cold Weather►Wear Appropriate Clothing – 3 LayersWear Appropriate Clothing – 3 Layers

Outer Layer: GortexOuter Layer: Gortex®® or Nylon – Break or Nylon – Break the Wind & Allow Some Ventilationthe Wind & Allow Some Ventilation

Middle Layer: Down or Wool – Absorb Middle Layer: Down or Wool – Absorb Sweat & Provide Insulation Even When WetSweat & Provide Insulation Even When Wet

Inner Layer: Cotton or Synthetic Weave – Inner Layer: Cotton or Synthetic Weave – To Allow Ventilation To Allow Ventilation

►Layering Creates Air Pockets – Helps Layering Creates Air Pockets – Helps Retain Body HeatRetain Body Heat

Cold Stress PreventionCold Stress Prevention►Wear Hat – Exposed Head:Wear Hat – Exposed Head:

Up to 40% Loss of Body Heat Up to 40% Loss of Body Heat

► Insulated Boots or FootwearInsulated Boots or Footwear Wear One Thick or Two Thin Pairs of SocksWear One Thick or Two Thin Pairs of Socks Too Many Socks Tighten Fit & Restrict Blood Too Many Socks Tighten Fit & Restrict Blood

FlowFlow

►Hands Loose Dexterity < 59Hands Loose Dexterity < 59OOFF►Change of Dry Clothing–If Clothes Gets WetChange of Dry Clothing–If Clothes Gets Wet►Do Not Wear Tight Clothing – Loose Air Do Not Wear Tight Clothing – Loose Air

Pocket InsulationPocket Insulation

Cold Stress PreventionCold Stress Prevention►Avoid Alcohol and CaffeineAvoid Alcohol and Caffeine

Increases Heat Loss Through VasodilationIncreases Heat Loss Through Vasodilation

►Take Breaks Out of the ColdTake Breaks Out of the Cold►Schedule Work During Warmer Parts of DaySchedule Work During Warmer Parts of Day►Older Workers or Certain Medical Older Workers or Certain Medical

ConditionsConditions May Be More Susceptible May Be More Susceptible

►Radiant HeaterRadiant Heater►Shielding Work Areas from Drafts & Wind to Shielding Work Areas from Drafts & Wind to

Reduce Wind ChillReduce Wind Chill

Cold Stress TrainingCold Stress Training►Proper Clothing & EquipmentProper Clothing & Equipment►Safe Work PracticesSafe Work Practices►Guidelines for Eating & DrinkingGuidelines for Eating & Drinking►Risk Factors That Increase Health Risk Factors That Increase Health

Effects of Cold ExposureEffects of Cold Exposure►How to Recognize Signs & Symptoms of How to Recognize Signs & Symptoms of

Hypothermia, Frostbite, & Trench FootHypothermia, Frostbite, & Trench Foot►Appropriate First Aid Treatment, Appropriate First Aid Treatment,

Including Warming ProceduresIncluding Warming Procedures

Heat StressHeat Stress

Heat StressHeat Stress►Body Produces/Stores More Heat Body Produces/Stores More Heat

Than You LoseThan You Lose Metabolism/ExerciseMetabolism/Exercise Heat AbsorbedHeat Absorbed

►Radiant Energy (Sun, Fire)Radiant Energy (Sun, Fire)►Conductive (Direct Contact)Conductive (Direct Contact)

►Primary Heat Loss – EvaporationPrimary Heat Loss – Evaporation Sweat/EvaporationSweat/Evaporation Function of Humidity & TemperatureFunction of Humidity & Temperature

Heat IllnessesHeat Illnesses►Heat RashHeat Rash

Clogged/Irritated Sweat GlandsClogged/Irritated Sweat Glands

►Heat CrampsHeat Cramps Painful Muscle Spasms–Electrolyte Painful Muscle Spasms–Electrolyte

ImbalanceImbalance

►Heat ExhaustionHeat Exhaustion Heavy Sweating/Pale Clammy SkinHeavy Sweating/Pale Clammy Skin Normal Heart Rate/Body TemperatureNormal Heart Rate/Body Temperature

►Exert ional Heat IllnessExert ional Heat Illness Stuporous Appearance, Nausea, High Stuporous Appearance, Nausea, High

Temperature, HeadacheTemperature, Headache

Heat Illnesses Heat Illnesses

►Heat StrokeHeat Stroke High Body High Body

TemperatureTemperature Hot, Red (Gray) Dry Hot, Red (Gray) Dry

Skin, Rapid PulseSkin, Rapid Pulse Confusion, Loss of Confusion, Loss of

ConsciousnessConsciousness Death is ImminentDeath is Imminent

►Heat Stroke First AidHeat Stroke First Aid Loosen Tight ClothingLoosen Tight Clothing Cool with Wet ClothCool with Wet Cloth If Conscious, Slowly If Conscious, Slowly

Give 4 oz of Water Give 4 oz of Water Every 15 MinutesEvery 15 Minutes

Get Victim to Get Victim to Emergency Room Emergency Room ASAPASAP

Heat Illness PreventionHeat Illness Prevention

►Drink FluidsDrink Fluids Water – 4 Cups (1 Quart/Hour)Water – 4 Cups (1 Quart/Hour) No Alcohol or Caffeine - DiureticsNo Alcohol or Caffeine - Diuretics

►EatEat Replace Electrolytes Lost by Replace Electrolytes Lost by

PerspirationPerspiration

Heat Illness PreventionHeat Illness Prevention

►AcclimationAcclimation Slow Process for Body to Condition Itself Slow Process for Body to Condition Itself

to Heatto Heat May Take Up to 10 DaysMay Take Up to 10 Days Quickly Lost in a Matter of DaysQuickly Lost in a Matter of Days

►Conditioning/General HealthConditioning/General Health Stay in Shape, Exercise RegularlyStay in Shape, Exercise Regularly Watch Your WeightWatch Your Weight

Cal/OSHA Heat Illness Cal/OSHA Heat Illness Regulation Regulation

Title 8 Cal. Code Regs., Title 8 Cal. Code Regs., §3395§3395

►Several Fatalities Due to Heat Stroke Several Fatalities Due to Heat Stroke in California in California ConstructionConstruction AgricultureAgriculture

►Became Permanent in April 22, 2006Became Permanent in April 22, 2006►Essentially Identical to Emergency Essentially Identical to Emergency

Regulation Regulation

Heat Illness Prevention Heat Illness Prevention Standard: ApplicationStandard: Application

►All Outdoor Places of EmploymentAll Outdoor Places of Employment►At Time When Environmental Factors At Time When Environmental Factors

for Heat Illness are Presentfor Heat Illness are Present Air TemperatureAir Temperature Relative HumidityRelative Humidity Radiant Heat, Conductive HeatRadiant Heat, Conductive Heat Workload Severity/DurationWorkload Severity/Duration Personal Protective Clothing/EquipmentPersonal Protective Clothing/Equipment

Outdoor EnvironmentsOutdoor Environments►AgricultureAgriculture►ConstructionConstruction►Equipment and Storage YardEquipment and Storage Yard►Loading DocksLoading Docks►TentsTents►Structures with One or More Open Structures with One or More Open

SidesSides Lack of Insulation/Heating From SunLack of Insulation/Heating From Sun Limited Air CirculationLimited Air Circulation

Potable Drinking WaterPotable Drinking Water

►Sufficient Quantity at Beginning of Sufficient Quantity at Beginning of Work ShiftWork Shift Can Begin Shift with Smaller Quantities if Can Begin Shift with Smaller Quantities if

Effective Replenishment Procedures Effective Replenishment Procedures Developed and ImplementedDeveloped and Implemented

► >>1 Quart/Employee/Hour for Entire 1 Quart/Employee/Hour for Entire ShiftShift >>2 Gallons/Employee/8-Hour Shift2 Gallons/Employee/8-Hour Shift

►Encourage Frequent Drinking of WaterEncourage Frequent Drinking of Water Thirst – Unreliable Indicator of Thirst – Unreliable Indicator of

DehydrationDehydration

Access to ShadeAccess to Shade►Available for Employee(s):Available for Employee(s):

Suffering from Heat Illness; orSuffering from Heat Illness; or Believe a Preventive Recovery Period is Believe a Preventive Recovery Period is

NeededNeeded►At Least 5 Minutes At Least 5 Minutes ►Cool Down (Metabolic Heat/Heart Rate)Cool Down (Metabolic Heat/Heart Rate)►RehydrateRehydrate

►Shade is:Shade is: Open to Air; orOpen to Air; or Provided with Ventilation or Cooling for a Provided with Ventilation or Cooling for a

Period of No Less Than 5 MinutesPeriod of No Less Than 5 Minutes►Access to Shade Permitted at All TimesAccess to Shade Permitted at All Times

Heat Illness Prevention Heat Illness Prevention TrainingTraining

►Employee TrainingEmployee Training►Supervisor TrainingSupervisor Training►Training Completed Prior to Training Completed Prior to

Assignment in Outdoor Assignment in Outdoor Environment with a Potential for Environment with a Potential for Heat IllnessHeat Illness

Employee TrainingEmployee Training► Risk Factors for Heat Risk Factors for Heat

IllnessIllness EnvironmentalEnvironmental PersonalPersonal

► Employer’s Employer’s Preventive Preventive Procedures Procedures

► Importance of Water Importance of Water ConsumptionConsumption

► Importance of Importance of AcclimationAcclimation

► Types/Signs & Types/Signs & Symptoms of Heat Symptoms of Heat IllnessesIllnesses

► Immediate Reporting Immediate Reporting Signs/Symptoms to Signs/Symptoms to SupervisorSupervisor

► Employer’s Employer’s Procedures Procedures Responding to Signs Responding to Signs & Symptoms& Symptoms

► Emergency Medical Emergency Medical ProceduresProcedures

Supervisor TrainingSupervisor Training►Same Information in Employee Same Information in Employee

TrainingTraining►Procedures for Supervisor to Procedures for Supervisor to

Implement Heat Illness Prevention Implement Heat Illness Prevention Program to Meeting Cal/OSHA Program to Meeting Cal/OSHA StandardStandard

►Procedures Supervisor to Follow:Procedures Supervisor to Follow: When Employee Exhibits Symptoms of When Employee Exhibits Symptoms of

Possible Heat Illness; andPossible Heat Illness; and For Emergency ResponseFor Emergency Response