The colder weather is here, and those of us that must work outside must be aware of the effects of cold stress, including hypothermia, trench foot and frostbite. When most people think of hypothermia, they think of frigid temperatures or blizzard-like conditions. Actually, hypothermia occurs most often in the spring and fall, rather than winter. A cold environment forces the body to work harder to maintain it's temperature. Cold air, water, and snow all draw heat from the body.
Wind chill is the combination of air temperature and wind speed.
So, while it is obvious that below freezing conditions combined with inadequate clothing could bring about cold stress, it is important to understand that it can also be brought about by temperatures in the 50's coupled with some rain and wind. When in a cold environment, most of your body's energy is used to keep your internal temperature warm. This allows exposed skin and the extremities to cool rapidly and increases the risk of frostbite and hypothermia. Combine this with cold water, and trench foot may also be a problem. This occurs when body heat is lost from being in a cold environment faster than it can be replaced.