Baby, it's Cold Outside!
Wednesday, December 19th, 2018
As we move deeper into the winter months with several weeks of Ole Man Winter presenting us with a variety of conditions, we’re still faced with the reality that, Baby, it’s cold outside! Given this, how can we avoid typical cold injures in 2019?
Our bodies work so hard in winter to maintain a core temperature of 98.6ºF. It does this through decreasing blood flow to extremities to keep internal organs warm. The downside is that it increases chance of frostbite in the extremities. Your body also starts to shiver to generate heat and, under prolonged cold exposure, our bodies slowly lose its body heat. This entire process happens much more quickly when we’re wet.
So what are the cold injuries we work to prevent? Hypothermia and frost bite.
Most cases occur between 30ºF and 50ºF and can occur in temperatures as high as 65ºF because these temperatures are so far below our core temperature! When in water, it can start at 72ºF! Our bodies lose heat through the skin primarily through radiation. This loss speeds up when skin is exposed to wind or moisture. If cold exposure is due to being immersed in cold water, heat loss can occur 25 times faster than it would if exposed to the same air temperature.
Symptoms of mild hypothermia include: shivering and chattering teeth; blue lips and fingers; and poor coordination. Moderate hypothermia symptoms include: mental impairment and confusion; disorientation and poor decision making; inability to take precautions from the cold; slower heart and breathing rates; and slurred speech. More urgently, symptoms of severe hypothermia: resembles death; unconsciousness; irregular or hard-to-find pulse; no shivering, and no detectable breathing.
What does first aid look like for those with signs and symptoms of hypothermia?
- Call for medical help
- •Move victim to shelter
- •Remove wet clothing
- •Apply direct body heat
- •Warm neck, chest, abdomen, and groin
- •Wrap victim in covers, if necessary
Frost bite is exposure of our bodies to severe cold temperatures or cold objects, It can affect fingers, toes, cheeks, nose and ears. These tissues can freeze at 30ºF! What’s worse, after having frost bite, these areas are susceptible to future frost bite. In extreme cases, frostbite may cause gangrene, amputation, or loss of function.
Frost bite symptoms include: sensations of coldness; tingling, stinging or aching sensations, skin feels numb or cold to the touch, skin is waxy and appears white; and skin blisters that turn red, then black.
How do we treat frost bite?
- Do not rub
- Use water between 102°F and 110°F
- Apply sterile dressing to blisters
- Do not thaw if risk of re-freezing
- Get medical attention
Dehydration is another risk we face in cold conditions. It’s important to drink plenty of liquids, especially when sweating due to exertion or heavy clothing.
Another important factor in assessing cold conditions is wind chill. Wind chill is the combined effect of air temperature and air movement or wind, so it’s important to check the weather throughout out the day to assess dangerous conditions.
Preventing cold injuries starts with identifying the hazard and working through the typical steps to eliminate or control for the hazardous cold conditions through engineering controls, administrative controls, and protective clothing as outline below.
Engineering controls – heated shelters, windscreens, on-site sources of heat like vehicle access, and thermally insulated tools and work surfaces.
Administrative controls include: frequent breaks or rotations; warming up on breaks; and working during warmest hours of the day
Protective clothing includes wearing: several layers of clothing; synthetic fibers next to skin to whisk away sweat (cotton can be hazardous!); water-repellent, wind-resistant outer clothing; hats, hoods, or face covers; insulated, waterproof footgear; insulated, waterproof gloves; and access to spare clothing.
Safe work practices include: fueling the body with high calorie foods; consuming warm soups and sweet drinks; avoiding coffee and caffeinated drinks, acclimating to cold conditions, staying in good physical shape, avoiding heavy perspiration – especially wearing cotton, minimizing prolonged sitting or standing, watching for symptoms of cold-related injuries, and not working alone in cold conditions.