The definition of “extreme cold” varies from region to region. In the south, near-freezing temperatures feel downright cold, while in the north it’s not surprising if the mercury dips well below zero this time of year.

No matter where you are, if you’re working outside on a daily basis the cold is going to affect you. Heat leaves the body more quickly, causing the body to work much harder to stay warm and keep a normal core temperature. If you’re not careful and properly dressed, this can lead to cold stress.

Cold stress is caused by a lowered skin temperature, which eventually drives down body temperature. This causes various illnesses and injuries ranging from hypothermia and frostbite to trench foot.

Besides just freezing weather, other factors can contribute to these complications, including exhaustion, wearing wet or damp clothing, not dressing properly for the weather and being out of shape. Pre-existing health conditions like hypertension, hypothyroidism and diabetes can also make a person more susceptible to cold stress.

OSHA doesn’t have a specific standard for working in extreme cold, but it does say employers should provide training on preventing, recognizing and treating cold-stress illnesses.

One of the most important factors in preventing cold stress is dressing properly when working outside in inclement weather. Recommendations include:

•    Wear layers of loose-fitting clothing. The inner layer should be moisture wicking.
•    Wear a hat that covers your ears. A lot of body heat escapes from your head.
•    Use a knit facemask.
•    Wear insulated, waterproof gloves.
•    Wear insulated and waterproof boots.

Other tips for workers include:

•     Monitor your physical condition and that of your co-workers. All workers at risk should know the signs of cold stress and what to do if symptoms develop.
•     Stay dry in the cold. Getting wet or sweating can increase heat loss from the body.
•     Keep extra clothing handy in case something gets wet.
•     Drink plenty of fluids. You can quickly become dehydrated in cold weather.
•     Use proper engineering controls (heaters, work shelters), safe work practices and personal protective equipment. 

For more on cold stress and first-aid recommendations, visit the OSHA guidelines or tips from the CDC.

And for more on dressing properly for extreme cold, we share some tips on clothing and layering from the experts at Under Armour.