heat cold stress

HEAT STRESS

1293 Airport Road

Beaver, WV 25813

Phone: (304) 253-8674

Fax: (304) 253-7758

E-mail: [email protected]

Vincent J. Giblin, General President

This material was produced under grant number 46C5-HT16 from the Occupational Safety and Health Administration, U.S. Department of Labor. It does not necessarily reflect the views or policies of the U.S. Department of Labor, nor does mention of trade names, commercial products, or organizations imply endorsement by the U.S. Government.

Operating Engineers National Hazmat Program

RECENT HEAT RELATED DEATHS

Korey Stringer 7-31-01– 27 Yrs Old 6’3” 335 lbs

Eraste Autin 7-25-01– 18 Yrs Old 6’2” 250 lbs

Preston Birdsong 8-13-00– 18 Yrs Old 5’11” 190 lbs


COMMON FACTORS(Worker vs. Athlete)

Protective clothingFocus on task at handJob security concernsDesire to succeedDesire to be acceptedMachismoPeer pressureDelayed thirst mechanism


U.S. HEAT STROKE STATS

At least 300 deaths/year7421 deaths from 1979-19981700 deaths in 1980 aloneCauses more deaths annually than

hurricanes, lightning, tornadoes, floods, and earthquakes combined

18 high school and college football player deaths since 1995

PHYSIOLOGICAL RESPONSES TO OVERHEATING

English Translation: What happens when you get too dang hot


“TOO DANG HOT RESULTS”

Excessive sweat loss results in dehydration

The body loses its ability to cool

Increased blood flow to skin causes decrease in organ function


HEAT-RELATED ILLNESSES

HEAT CRAMPS

HEAT EXHAUSTION

HEAT STROKE


HEAT CRAMPS

Caused by excessive loss of electrolytes

Early warning sign of heat stress

Painful cramps usually in legs or abdomen

Stop activity, hydrate, rest in cool place

Get medical attention if condition continues


HEAT EXHAUSTION

The body’s response to excessive water and electrolyte loss

Stop activity and seek treatment immediately


HEAT STROKE

The body’s cooling mechanism shuts down

50% that reach the heat stroke stage die even with medical attention


LIVE OR DIE?

HEAT EXHAUSTION

Skin is pale Excessive sweating May faint but usually

conscious Headache Nausea and vomiting Blurred vision Dizziness

HEAT STROKE

Skin is redNo sweatingUnconscious or

incoherent


TREATMENT

HEAT EXHAUSTION

Call 911Rest in cool placeLoosen and remove

unnecessary clothingShower or sponge

with cool water

HEAT STROKE

Call 911 Immediate,

aggressive, effective cooling

DO NOT give anything by mouth

Transport to hospital


HUMAN RISK FACTORS

Poor nutritionPoor physical

conditionHigh and low % body

fatPrevious heat illness

Lack of acclimatizationOver 40 Illness (diabetes, asthma)PregnancyDiet plans


ENVIRONMENTAL RISK FACTORS

Air temperatureDirect sunlightRadiant heatHumidityLittle air movement


JOB RISK FACTORS

Work intensityWork durationLocation (roof, road, enclosure)Clothing (weight, impermeability)Respiratory protection


WORKER RESPONSIBILITY

Follow instructions of IH and health care professionals

Be watchful for symptoms (self and others)Properly hydrate (before, during, after)Get adequate restAvoid alcohol, unnecessary medication,

and caffeine


MANAGEMENT RESPONSIBILITY

Ensure that environmental conditions are monitored

Adjust work practices as necessary

Be watchful for signs of overexposure

Know workers medical history

Assure workers are properly trained

Conduct pre and post job safety meetings

Assure that affected workers receive treatment


MONITORING

Environmental monitoring– WBGT (heat index= temp+humidity+radiant) used

for guidance in establishing work/rest ratioPersonnel monitoring

– Oral thermometer– Ear probe– R*&%$! Thermometer– Core Temp– Pulse rate– Blood pressure


COOLING WEAR

Traditional ice vestsChem-pack vests, headbands, & bandanasActive cooling garment (water circulating)SAR and PAPR with active cooling

systemsNew material development (breathable,

lighter weight, waterproof)


COLD STRESSCOLD STRESSHypothermiaHypothermia


Cold Stress Cold Stress (Hypothermia)(Hypothermia)

• Acute problem resulting from prolonged Acute problem resulting from prolonged cold exposure and heat losscold exposure and heat loss

• ““Hypo” (too little) “Thermia” (heat)Hypo” (too little) “Thermia” (heat)• 750 deaths/year in USA750 deaths/year in USA• Generally doesn’t present the same level Generally doesn’t present the same level

of danger as heat stressof danger as heat stress– Does not occur as quicklyDoes not occur as quickly– Workers will simply come in out of the coldWorkers will simply come in out of the cold


MAJOR CAUSESMAJOR CAUSES• Cold TemperaturesCold Temperatures

– 41 degrees F is cold enough with other contributing 41 degrees F is cold enough with other contributing factorsfactors

• Improper clothing and equipmentImproper clothing and equipment

• WetnessWetness– Sweating, contact with waterSweating, contact with water– Water conducts heat away from the body 25 Xs faster Water conducts heat away from the body 25 Xs faster

than airthan air


Contributing FactorsContributing Factors• FatigueFatigue

• DehydrationDehydration

• HungerHunger

• Alcohol intakeAlcohol intake


Cold Stress HazardsCold Stress Hazards• SYSTEMICSYSTEMIC

– HypothermiaHypothermia• LOCALIZEDLOCALIZED

– FrostnipFrostnip– FrostbiteFrostbite– Trench FootTrench Foot


Signs and SymptomsSigns and Symptoms• HypothermiaHypothermia

– Body temp <95 degrees FBody temp <95 degrees F– EuphoriaEuphoria– Slow weak pulseSlow weak pulse– Slurred speechSlurred speech– ShiveringShivering– UnconsciousnessUnconsciousness


Signs and SymptomsSigns and Symptoms• Frostnip/FrostbiteFrostnip/Frostbite

– Itching/burning/numbItching/burning/numb– Skin color changeSkin color change

• WhiteWhite• Grayish yellowGrayish yellow• Reddish violetReddish violet• BlackBlack

• Trench FootTrench Foot– Severe pain/itch/tingleSevere pain/itch/tingle– SwellingSwelling– BlistersBlisters


First AidFirst Aid• HypothermiaHypothermia

– Move to warm areaMove to warm area– Remove wet clothingRemove wet clothing– Modest external Modest external

warmingwarming• Blankets/heat packsBlankets/heat packs

– Drink warm sweet Drink warm sweet fluids (non-caffeinated)fluids (non-caffeinated)

– Transport to hospitalTransport to hospital

• Frostnip/FrostbiteFrostnip/Frostbite– Move to warm areaMove to warm area– External warmingExternal warming

• Warm waterWarm water

– Drink warm sweet Drink warm sweet fluids (non-caffeinated)fluids (non-caffeinated)

– Treat as burn (do not Treat as burn (do not rub)rub)

– Transport to hospitalTransport to hospital


Body Response Body Response MechanismsMechanisms

• VasoconstrictionVasoconstriction– Blood vessel constrictionBlood vessel constriction– Reduces heat loss/makes skin better insulatorReduces heat loss/makes skin better insulator

• ShiveringShivering– Increases body temp as vasoconstriction failsIncreases body temp as vasoconstriction fails

• **NEITHER ARE AS EFFECTIVE AS **NEITHER ARE AS EFFECTIVE AS SWEATING AND ACCLIMATION ARE SWEATING AND ACCLIMATION ARE FOR HEAT STRESSFOR HEAT STRESS


Behavior Is The Key!Behavior Is The Key!• Behavior is the primary protection factor Behavior is the primary protection factor

for cold stress preventionfor cold stress prevention– Increase clothing insulationIncrease clothing insulation– Increase activityIncrease activity– Seek warm locationSeek warm location– Get the H$!! out of thereGet the H$!! out of there


Cold Stress SolutionsCold Stress Solutions• Engineering Controls-Engineering Controls- Warming shelters, spot Warming shelters, spot

heating (i.e. hand warmers), minimize air heating (i.e. hand warmers), minimize air movement (shielding)movement (shielding)

• Work Practices- Work Practices- fluid replacement, change wet fluid replacement, change wet clothes immediately, buddy systemclothes immediately, buddy system

• Administration Controls-Administration Controls-work/rest cycles, work/rest cycles, warm period work, allow for productivity warm period work, allow for productivity reductionsreductions

• PPEPPE


Clothing TipsClothing Tips• Dress in LayersDress in Layers

– Add or remove for comfortAdd or remove for comfort– Allows free movement and dexterityAllows free movement and dexterity

• Layer closest to skin should be “water Layer closest to skin should be “water vapor permeable”vapor permeable”– Wicks away moisture, allows evaporation, Wicks away moisture, allows evaporation,

prevents accumulationprevents accumulation


This material was produced under grant This material was produced under grant number 46C5-HT16 from the Occupational number 46C5-HT16 from the Occupational

Safety and Health Administration, U.S. Safety and Health Administration, U.S. Department of Labor. It does not Department of Labor. It does not

necessarily reflect the views or policies of necessarily reflect the views or policies of the U.S. Department of Labor, nor does the U.S. Department of Labor, nor does

mention of trade names, commercial mention of trade names, commercial products, or organizations imply products, or organizations imply

endorsement by the U.S. Government. endorsement by the U.S. Government.


ENDEND•This publication was made possible by grant numbers 5 U45 ES06182-13 AND

5 U45 ES09763-13 from the National Institute of Environmental Health

Sciences (NIEHS), NIH. Its contents are solely the responsibility of the authors and do not necessarily represent the

official views of the NIEHS, NIH.

heat cold stress

Health & Medicine