Cold Stress Factors Cold stress is the loss heat to the environment due to: – Low temperature: Cold air temperatures The Cold will forces body to work harder to maintain it’s temperature The Cold air, water, and snow all draw heat from the body – Wind: High velocity air movement Wind chill is combination of air temperature and wind speed and capable of bringing cold stress in the 50’s with rain and wind – Wetness: Contact with cold water or surfaces The body’s first response to cold stress is to conserve body heat by reducing blood circulation through the skin.
Cold Stress Factors Normal body temperature is 98.6 degrees F. When body temperature drops below 86 degree F, the temperature control system becomes ineffective. When body temperature drops below 59 degrees F, it begins to experience impairment of many functions.
Basic Hypothermia Concepts Hypothermia means “ Low Heat ” and is a potentially serious health condition The major injuries associated with cold temperatures are: – General hypothermia – Immersion hypothermia – Frostbite Prolonged exposure to cold causes the body to lose energy faster than it is produced
Conditions Affecting Hypothermia Aging, allergies, poor circulation & illness Self-imposed conditions, such as alcohol use, anti-depressants, or sedatives – The body may have difficulty regulating temperature. Wet clothing, windy conditions, & poor physical condition
Hypothermia Signs & Symptoms Mild Hypothermia (98 – 90 degrees F) – Shivering – Numbness in limbs, loss of dexterity, and clumsiness – Slurred speech – Memory loss – Pale, cold skin
Hypothermia Signs & Symptoms Moderate Hypothermia (90 – 86 degrees F) – Shivering stops – Confused and irrational – Unable to walk or stand Severe Hypothermia (86 – 78 degree F) – Severe muscle stiffness – Very sleepy or unconscious – Ice cold skin – Reduced pulse – Death is a possibility
Safety Procedures Proper treatment depends on the severity of the hypothermia – Mild Hypothermia Move to warm area Stay active Remove wet clothes and replace with dry clothes or blankets, cover the head Drink warm (not hot) sugary drink
Safety Procedures Cont. Moderate Hypothermia – Use all of the Mild Hypothermia procedures and plus the following: Call 911 for an ambulance Cover all extremities completely Warm center of body first with warm objects Severe Hypothermia – Call 911 for an ambulance – Treat the victim very gently – Do not attempt to re-warm, the victim should receive treatment in a hospital
Frostbite Frostbite occurs when the skin actually freezes and loses water. Freezing of deep layers of skin Pale, waxy-white skin color Skin becomes hard and numb Usually affects: – Fingers and hands – Toes and feet – Ears and nose
Frostbite Cont. Three stages of frostbite – Frost nip Individual experiences a “pins and needles” sensation and skin is unusually white and soft. – Superficial Characterized by waxy feeling, frozen, numb, and possible blistering skin. – Deep The most serious type of frostbite affects the blood vessels, muscles, nerves, tendons, and even bone -leading to possible permanent damage, blood clots, and death of body tissues.
Emergency Procedures What to do: – Call – Move to warm area – Remove wet clothing – Drink warm sweet fluids – Do not rub the affected area – Wrap in soft cloth
Preventing Cold Stress Engineering Controls – Provide for general or spot heating, including hand warming. – Use insulating material on equipment handles. – Provide wind barriers if possible. Administrative & Work Practices – Train employees about cold stress, cold-related disorders, and first aid. – Schedule work at warm times, if possible. – Move work to warm areas, if possible. – Take regular breaks in warm places.
Preventing Cold Stress Cont. Administrative & Work Practices Cont. – Use the buddy system (work in pairs when possible) – Drink warm, sweet fluids, avoid caffeine and alcohol – Recognize the environmental conditions that lead to cold stress Personal Protection – Properly selected, insulated, and layered clothing – Waterproof boots and gloves – Eye protection for snow or ice-covered terrain
Cold Stress Revision Dated: September 29 th, 2014