Frostbite Risk Broken Down by Temperature

Frostbite risk by temperature can be reduced with the right clothing and strategy.
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Frostbite Risk Broken Down by Temperature: Plan Ahead

Frostbite is injury to the skin and if severe, underlying tissue, resulting from prolonged exposure to freezing temperatures often exacerbated by wind chill. And the best way to avoid frostbite is to prevent it.

Most of the time, it's exposed skin that's at risk of frostbite, but if temperatures are cold enough and one remains in the cold long enough with insufficient wardrobe protection, even unexposed skin can freeze.

The following guidelines, as put forth by Environment Canada, can give you a better idea of the level of frostbite risk to be expected depending on the temperature. Always remember when determining frostbite risk as categorized below to factor in any drop in temperature due to wind chill.

 

0°C to -9°C (32°F to 15.8°F): Low Frostbite Risk

There might be a slight increase in discomfort from prolonged exposure to cold. Otherwise, there's not much to worry about in these temperatures.

Advice:

 

-10°C to -27°C (14°F to -16.6°F): Low Frostbite Risk

Not the most comfortable temperatures, note that there is a risk of hypothermia with prolonged exposure to this temperature range if outdoors without adequate protection.

Advice:

  • dress for the weather, preferably in layers: consider at least three layers with the third being a wind-resistant coat
  • choose a down filled coat (polyester fill and even wool coats are inadequate for these temperatures)
  • cover exposed skin with a hat/earmuffs/tuque, gloves, scarf/neck tube and insulated, water-resistant boots, all a MUST at this temperature range
  • be active, keep in movement
  • stay dry

 

-28°C to -39°C (-18.4°F to -38.2°F): Risk of Frostbite in 10 to 30 Minutes

Adequate protection from the elements is absolutely essential at this point as the risk of frostbite as well as hypothermia are significantly heightened as soon as temperatures, with or without wind chill, dip below -27°C (-16.6°F). It's highly recommended that outdoor activities be engaged in at least pairs if not groups in order to check each other's faces for possible signs of frostbite.

Advice:

  • follow all previously listed advice on what to wear and keep in movement, this is not the time to stand or sit still
  • keep an eye out for whiteness or numbness in the skin, and
  • stay dry

 

-40°C to -47°C (-40°F to -52.6°F): High Risk of Frostbite of Exposed Skin in 5 to 10 Minutes (Even Less if Winds Are Sustained Over 50km/h (31 miles/h)

Adequate protection from the elements is absolutely essential at this point as the risk of frostbite as well as hypothermia are imminent if exposure is prolonged without adequate protection and shelter. Outdoor activities should be engaged in at least pairs if not groups in order to check each other's faces for possible signs of frostbite.

Advice:

  • follow all previously listed advice on layering and on the importance of staying active and in movement
  • periodically check for whiteness or numbness in the skin
  • stay as dry as possible

 

-48°C to -54°C (-54.4°F to -65.2°F): Very High Risk of Frostbite of Exposed Skin in 2 to 5 Minutes (Even Less if Winds Are Sustained Over 50km/h (31 miles/h)

Adequate protection from the elements is absolutely essential at this point as the frostbite as well as hypothermia are virtually guaranteed if exposure is prolonged without adequate protection and shelter. Outdoor activities should be engaged in at least pairs if not groups in order to check each other's faces for possible signs of frostbite.

Advice:

  • follow all previously listed advice on layering, which warm clothing to wear and how to keep dry and in movement at all times
  • be ready to cut short outdoor activities or even cancel them
  • consider staying indoors

 

-55°C or colder (-67°F or colder): Extremely High Risk of Frostbite of Exposed Skin in 2 Minutes or Less

Stay indoors. Outdoor conditions are too hazardous for any kind of activity.