Prolonged exposure to cold can lead to a drop in body temperature that can potentially become dangerous. This condition is known as hypothermia, and it is something that sailors may encounter given the wet and cold conditions in which they operate. I don't worry too much about hypothermia while sailing in the warm British Virgin Islands, however it should be noted that hypothermia can develop even when temperatures are not very low. Multiple people have died in my home state of Colorado falling in the water sailing in lake Dillon, a high alpine lake where air temperature can warm but the water frigid. In New England where I grew up, as in many other places, the risk increases in the spring and fall when the weather starts to cool down. The longer the exposure and the more wet and cold it is, the higher the risk of developing hypothermia.
Lake Dillon in Colorado
Causes of Hypothermia
Exposure to cold is what leads to Hypothermia, especially in wet environments. Water cools the body about 25 times faster than air, so a person is most likely to become hypothermic if they fall in cold water or get wet while onboard.
Avoiding heat loss is the main goal. Do everything you can to stay dry and to avoid falling in the water. This may include wearing a wet suit to help keep your body warm, as well as wearing gloves and a hat to prevent heat loss from your head and hands. Keep a set of dry clothes you or your crew can change into the event you get wet. Other supplies that can help reverse or prevent hypothermia include blankets and something to heat up liquid you can drink to warm up, such as a tea kettle.
How You Know You're Becoming Hypothermic
Hypothermia is a gradual process, hence learning to recognize its signs can help you take action before things get worse.
With mild hypothermia, most people will simply start feeling cold and may develop slurred speech or start shivering. As it progresses and becomes more moderate, a hypothermic person may become more confused, sleepy, and possibly even stop shaking as the body begins to shut down. As the body continues to cool and the hypothermia becomes more severe, their body will eventually reach a point where it no longer functions properly, causing the person to lose consciousness, go into respiratory distress, and if untreated, possibly die.
Someone with hypothermia should be kept warm and dry. Get them somewhere dry, remove their wet clothes, and cover them with blankets. Try to keep their head covered to prevent additional heat loss.
Focus on their core, not their extremeties. Do not rub their arms and legs, as this can cause their veins to dilate and take body heat away from core organs like their heart and brains, and possibly lead to shock.
If they are conscious and able, give them something hot to drink like tea or hot water. Do not give them alcohol or caffeine. Alcohol creates the illusion of feeling warm, however it actually lowers your core body temperature. This is because it is a vasodilator, causing your blood vessels to dilate which increases the volume of blood close to your skin's surface that is in contact with the cold environment. The greater the volume of blood in close contact to the air or water around you, the faster you will cool.
If hypothermia is moderate or severe, you may need to seek medical help. Don't be afraid to cut your sailing trip short and return to port if necessary. You can also use VHF channel 16 to contact the coast guard, or if within cell coverage, dial 911.
Studying For The ASA 103 Exam
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