Cold Weather Injuries, Hypothermia, Frostbite, Frostnip, Trenchfoot, Immersion Foot, Chilblains, First Aid
Extreme cold weather is a dangerous situation
that can bring on health emergencies in
susceptible people, such as those without
shelter, outdoor enthusiasts, and those who in
an area that is poorly insulated or without heat.
What constitutes cold injury and its effects can
vary across different parts of the country. In
regions relatively unaccustomed to winter
weather, near freezing temperatures are
considered factors for “cold injury.” Whenever
temperatures drop decidedly below normal
and as wind speed increases, heat can more
rapidly leave the body. These weather-related
conditions may lead to serious health
When exposed to cold, your body loses heat faster
than it can be produced. Prolonged exposure to
cold will eventually use up your body’s stored
The result is hypothermia, or abnormally low body
A body temperature that is too low, body reduces
circulation to extremeties to heat core (including brain)
making the victim unable to think clearly or move well.
This makes hypothermia particularly dangerous because a
person may not know it is happening and will not be able to
do anything about it.
vary based on how long you
have been exposed to the
Loss of coordination
Slowed pulse and
Loss of consciousness
And Obviously THEY MAY BECOME
IRRITABLE AND IRRATIONAL
Move the victim into a warm room or shelter
Remove their wet clothing, replace with warm dry
clothing or blankets, if possible.
Warm the center of their body first-chest, neck,
head, and groin using an electric blanket, if
available; or use skin to skin contact under loose,
dry layers of blankets, clothing, towels, or sheets.
Have victim drink warm sugar water or sports
drinks, if alert. No caffeine or Alcohol.
NO BODY RUBBING OR WARM WATER
This can stop their heart
No Pulse… CPR
Heat is lost 25 times faster in water!!!
Keep all clothing on. Button, buckle, zip, & tighten all
collars, cuffs, shoes, and hoods.
Keep head out of water and covered with hat or
hood… if possible
Get out, or find something to float on
Swimming reduces survival time by 50%, so only do so
in extreme situation, in close proximity to your goal.
To conserve body heat
Trapped layer of water provides insulation slowing loss of heat
Fold arms across chest, keep thighs together, bend knees, cross
Multiple People: Huddle chests together closely.
Chilblains are caused by the repeated exposure
of skin to temperatures just above freezing to
as high as 60degrees F. The cold exposure
causes damage to the capillary beds (groups of
small blood vessels) in the skin. This damage
is permanent and the redness and itching will
return with additional exposure. The redness
and itching typically occurs on cheeks, ears,
fingers, and toes.
Redness (Possibly Red Pimples)
Possible ulceration in sever cases
Slowly warm the skin
Use corticosteroid creams to relieve itching and
Keep blisters and ulcers clean and covered
Trench foot, also known as immersion foot, is
an injury of the feet resulting from prolonged
exposure to wet and cold conditions. Trench
foot can occur at temperatures as high as 60
degrees F if the feet are constantly wet. Injury
occurs because wet feet lose heat 25-times
faster than dry feet. Therefore, to prevent heat
loss, the body constricts blood vessels to shut
down circulation in the feet. Skin tissues begins
to die because of lack of oxygen and nutrients
and due to the buildup of toxic products.
Reddening of the skin
Blisters or ulcers
Bleeding under the skin
Gangrene (the foot may turn dark purple, blue,
Remove shoes/boots and wet socks
Dry their feet
Avoid walking on feet, as this may cause tissue
A common military practice to reduce chance
of TF is to change socks every few hours.
An untreated chilblain may develop into
frostnip. Frostnip freezes the outer layers of
fingers, toes, face and ears. Other than
exposure to severe cold, contact with cold
metal or liquid is often the cause. Poor
circulation in the extremities worsens the
situation. If treated immediately, the injury is
generally reversible. If not, the condition
develops further into the dangerous frostbite
Looks a lot like Frostbite: White and Waxy, but
rubbery, not hard since the deep layers are not
Turns Red, Painful, and Swollen when rewarmed
Similar to Immersion Foot
Remove victim from cold wet environment.
Remove shoes/boots and wet socks
Dry their feet
Avoid walking on feet, as this may cause tissue damage
Contact with warm object (Hands, Breath, Victim’s Own
The affected part will often tingle & become red during
A common military practice to reduce chance of TF
is to change socks every few hours.
Frostbite is an injury to the body that is caused
by freezing. Frostbite causes a loss of feeling
and color in the affected areas. It most often
affects the nose, ears, cheeks, chin, fingers, or
toes. Frostbite can permanently damage body
tissues, and severe cases can lead to
amputation. In extremely cold temperatures,
the risk is increased in people with reduced
blood circulation and among people who are
not dressed properly.
Reduced blood flow to hands and feet (fingers
or toes can freeze)
Bluish or pail, waxy skin
The following pictures are graphic in nature
and show the severity and the affects of
Get next to a fire or into a warm room as soon as possible and
remove tight clothing.
Unless absolutely necessary, do not walk on frostbitten toes-this
increases the damage.
Immerse the affected area in warm (105F)-not hot-water (the
temperature should be comfortable to the touch for unaffected
parts of the body.
Don’t Pour it over the area, you will cause damage!
This should take 25-40 min.
Warm the affected area using body heat; for example, the heat of
an armpit can be used to warm frostbitten fingers.
Do not rub or massage the frostbitten area; doing so may cause
Do not use a heating pad, heat lamp or heat of a stove, fireplace, or
radiator for warming. Affected areas are numb and can be easily
Gangrene (permanent cell death), can occur
when tissue is frozen and certain chemical
changes can occur in the cells.
Wind-chill involves the combined effect of air temperature and
air movement. Wind-chill cooling rate is defined as heat loss
(expressed in watts per meter squared) resulting from the
effects of air temperature and wind velocity upon exposed
skin. The higher the wind speed and the lower the temperature
in the work environment, the greater the insulation value of the
protective clothing required. Chart 1 compares the effects of air
temperatures with and without wind. For example, when the
air temperature is -28.9šC (-20šF) there is little danger of flesh
freezing with no wind, increased danger with a wind of 8
km/h, and extreme danger with a wind of 32 km/h or more.
When air speed and temperature produce a chill temperature
of -32šC (-25.6šF), continuous skin exposure should not be
permitted. Unprotected skin will freeze only at temperatures
below -1šC (30.2šF), regardless of wind speed.
Cold conditions can be expected in the coming
months. Furthermore, open exposed areas, mean
that windy conditions create a greater hazard in
cold environments and can contribute significantly
to cold temperatures (also know as the wind chill
factor). The collective effect of these conditions is
heat loss which places extra demands on the body.
For example, a drop in core body temperature of
just 1 degree C causes the muscles to shiver, which
in turn can lead to low blood sugar levels
(hypoglycemia) and reduced energy and
BLISTERS-the friction of wet socks and badly
fitting footwear can cause blisters to the toes, feet,
and the heels.
SPRAINS AND STRAINS-cold muscles and
connective tissues have less elasticity and are
therefore more prone to injury. Falls are also more
likely when sporting performance is reduced in
cold conditions, and this increases the likelihood of
these soft tissue injuries. Ligaments and muscles
spanning the knees, shoulders, wrists, and spinal
joints are the most common injuries of falls.
SUNBURN-ultraviolet radiation is present,
even in cold and cloudy conditions. This, and
the reflections off the snow, can cause sunburn
to exposed skin. What many people may think
is ‘windburn’ is actually sunburn.
SNOW BLINDNESS-this is sunburn of the
cornea of the eye, caused by ultraviolet
radiation. Symptoms include painful, watery
eyes and temporary blurring of vision.
Listen regularly to weather reports and avoid
weather extremes, such as a predicted
The best way to avoid many cold related
injuries in winter is to maintain an adequate
fitness level all year round.
Condition the muscles particular to your
chosen winter activities for at least a few weeks
or months beforehand.
Acclimatize yourself to exercising in
Treat any ailments you may have before
taking part in winter activities. Feet are
particularly vulnerable to cold, so if you
have a pre-existing medical condition
that can affect your feet, such as bunions
or diabetes, see your doctor for
information and advice before engaging
in cold weather.
Wear insulating, lightweight, multiple layers of
clothing as this traps more body heat than one
bulky layer. This also allows you to add or subtract
layers according to your comfort.
Wear adequate headgear since a lot of body heat is
lost through the scalp.
Avoid getting wet, THIS MEANS SWEATING
BECAUSE YOU WORKED TOO HARD! Wear
outer layers that waterproof and breathable.
Pit zips on jackets and zip on pants are useful to
release heat when you’re exerting excessively and
in danger of overheating.
Take spare glove, socks and hat in case the ones
you are wearing get wet.
Wear appropriate footwear (such as insulated and
waterproof shoes) and wear a blend sock that
wicks sweat away from the skin.
Make sure all footwear fits you properly. Footwear
that is too tight or too loose will cause a wide
range of avoidable injuries, including impaired
blood circulation (which could contribute to
frostbite) and blisters.
Wear close fitting sunglasses or goggles to help
avoid eye injuries.
Never go alone in extreme cold weather. With a
partner you can use the buddy system to check for
signs of hypothermia.
Be aware that you are exposed to UV radiation
even on cold or cloudy days.
Drink plenty of water before, during and after cold
Don’t drink alcohol. While and alcoholic drink
seems to warm you up, it actually narrows your
blood vessels, particularly those in the hands,
which can increase your risk of hypothermia.
Carry some snacks or energy bars as fatigue
increases the risk of injury.
Cold muscles, tendons and ligaments are
vulnerable to injury. Warm up thoroughly
before performing any work or activities in
cold temperatures. Remember to take cold
temperatures into account and spend more
time warming up than usual. Back pain and
muscle strains are always more common in
If you are wet, you can actually use snow on
the skin to dry it off quickly, but you must get
to a heat source right away.
When cold environments or
temperatures can not be avoided,
you should follow these
recommendations to protect yourself
from cold injury:
Wear several layers of loose clothing. Tight
clothing reduces blood circulation.
Boots should be waterproof and insulated.
Wear a hat.
Make sure to protect ears, face, hands, and feet.
Move into warm locations during breaks.
Spend extra time loosening your body
Monitor your physical condition and that of your
Acclimatize yourself to the cold weather
Avoid touching cold metal surfaces with bare skin.