COLD WEATHER ISSUES
Cold Weather Injuries
WET COLD > 14 F average 24h Freeze at night then thaw during day--ground slushy--wet snow/rain DRY COLD < 14 F average 24h Ground frozen--dry snow--no thaw
Summary of conditions:
Wet-cold conditions occur where variations in day and night temperatures cause alternate freezing and thawing. These conditions are often accompanied by wet snow and rain causing the ground to become slushy and muddy. Wet cold requires clothing with a waterproof or water-repellent, wind- resistant outer layer, and an insulated inner layer sufficient for moderately cold weather of 14°F and above. Waterproof footwear is essential.
Dry-cold conditions occur when average temperatures are lower than 14° F. The ground is usually frozen and the snow dry. These low temperatures and wind increase the need to protect the entire body. Dry cold requires layered clothing that insulates against a wind-chill. The inner layers of insulation must be protected by a water-repellent, wind-resistant outer layer.
Intense cold air temperatures ( -5 to -25°
F) are in the range where materials begin to change, adversely affecting operations. Fuels gel, back blast areas triple, artillery fires drop 100 per 1000 meters, water in containers freezes quickly. Appropriate protective clothing is required.
Extreme cold (below -25° F) inhibits full-scale combat. Special fuels and lubricants are required, rubber becomes stiff and brittle, and close tolerances are affected. Operator personnel must have special protection from the elements.
Water, Food, Shelter
* Will to survive* --Training/equipment
Head 60-80% of body heat
Loose, layered clothes
(air insulation layers on/off)
(mittens/socks on rucksack
unfolded, near body
near top of shelter
inside sleeping bag shell
keep sleeping bag dry)
Overheating can cause perspiration which can lead to hypothermia in cold weather situations.
COLD WEATHER INJURIES
FACTORS THAT INFLUENCE COLD WEATHER INJURIES (CWI)
Wind Chill Factor
Type of Mission
Alcohol, Drugs, Tobacco
Sharp Changes in Weather
PREVENTION OF COLD WEATHER INJURIES
Proper Use of Gloves/Headgear
Hypothermia is when your bodys heat loss exceeds the rate that your body can produce it. Your body can produce only a limited amount of heat to keep yourself warm. When your body is producing as much heat as it can and your body temperature is still lowering, you are suffering from hypothermia. Hypothermia can occur no matter what the temperature is.
It is important to know the symptoms and treatment for hypothermia.
CAUSES: Heat loss exceeds heat production Wind/water chill
Radiation--heat like light
Conduction--sitting on cold surface--handling cold objects
Respiration--breathing cold air
Symptoms: Intense shivering
Feeling of deep/cold numbness
Blueness of skin
Slow, weak, irregular pulse
Retreat inward psychologically
Treatment: Immediately raise body temperature
Shelter from wind and weather
Insulate from ground
Replace wet clothing with dry
Increase exercise if possible
Give hot drinks and food
Get in warm sleeping bag
Shared body warmth
Hot packs/hand warmers under armpits and groin area
Cause: Not consuming as much water as the body uses
Symptoms of normal dehydration: Higher temperature
Poor skin tugor
Dryness of mouth and throat
Symptoms of SEVERE dehydration: Similar to hypothermia
Typical hypothermia/dehydration differentiation test:
Cold belly-- hypothermia
Cold weather dehydration can lead to total body core cooling.
Cause: Exposure to wet and cold around freezing Symptoms: Feet and toes are pale and numb, cold, and stiff NOTE: If preventive action not taken at this stage feet will swell and become painful!
Treatment: Do NOT rub or massage
Clean carefully with soap and water if indoors
Dry, elevate, and expose to room temperature
Stay off feet and replace socks
Cause: Prolonged immersion in cold water < 50 F or in wet footwear > 12 hours. Aching and stinging pain on prolonged exposure. Initially no unusual Symptoms: Sensations of pain. Shin becomes shriveled and soft. NOTE: Handle gently--same as trench foot.
Cause: Freezing of skin or tissues due to exposure to temperatures at or below freezing.
Commonly by exposure to liquids that freeze at low temperatures such as gasoline, cleaning solvents, and salt water, or high velocity wind flow or metal surfaces.
EXPOSURE CAN OCCUR IN MINUTES!
Wind or contact with wet clothing may produce an effective temp in freezing range when air temperature is above freezing.
SYMPTOMS: First degree: Aching, tingling sensation with cold and numbness. Skin usually turns red. Second degree: Pale grey and waxy white. Third degree: Black--no feeling no blood flow
Handle gently--same as trench foot. DO NOT use water to warm affected areas.
CHEEKS: Cover with warm hands until pain returns FINGERS: Place uncovered under arm pits or belly next to skin. FEET: Bare feet against belly of companion, under clothing avoid rubbing or massaging. Dont pop blisters! CLOTHING: DRY, and proper for weather. EXERCISE: Routine exercise of face, fingers, and toes.