Our winters in The County are so very long, that one of the first things folks want to do, when the ice is gone, is to get out on our pristine rivers and lakes.
But before you get out there, it is critical that you know the facts about cold water.
The specific information in this column, in terms of human physiological response to cold water, comes from the National Center for Cold Water Safety.
Have you ever wondered why, when reading of a drowning, the incident report sometimes states that the victim jumped into the water and never resurfaced? Well, here’s the reason. When the body is immersed in cold water, the physiological response is to gasp, to take in a sudden breath (or breaths). If you are still under the surface of the water, those “breaths” will be water and not air. And here’s the shocker: it only takes about five ounces of water in the lungs, which is about two big gulps, to drown a person. And when that happens, the person does not resurface.
KEY POINT: Cold shock drowning, described above, is just as possible between 50 and 60 degrees, as it is at 35 degrees.
The problem is, the average person does not think “life threatening” when they hear about water temperatures in the 50s.
So let’s back up just a bit. Where on the Fahrenheit temperature scale does “cold water” start?
Well, surprisingly, problems can begin to arise with water temps in the upper 60s.
Here’s what starts to happen at different water temperatures.
Controlling your breathing becomes progressively more difficult as water temperatures fall from 70, down through the 60s.
When the water temperature gets down into the 50s, there is a total loss of breathing control. You become unable to control gasping, and if there are even just small wavelets on the lake, you will “gasp in” some of that water, and over a period of time, you will reach the “drowning threshold” of five ounces of water in the lungs. This is known as gradual drowning.
Hypothermia, which is a potentially fatal lowering of the body’s core temperature, is also a great danger in cases of cold water immersion. However, when you look at the charts showing that even in ice-cold water, it can take an hour or more for hypothermia to kill a person, it makes some folks think that cold water is not as dangerous as it really is. People think that there would be plenty of time for self-rescue or to be rescued.
But here’s the problem. With water temperatures between 60 and 70 degrees, with no protective clothing, loss of coordination occurs in 30 to 40 minutes, with exhaustion or unconsciousness occurring in 2 to 7 hours, depending on the individual. Now lower that water temperature down into the 50s, and you are talking about loss of coordination in only 10 to 15 minutes, with unconsciousness in only 1 to 2 hours.
So, to sum up, drowning from cold water immersion can occur in three primary ways: the “never resurfaced” scenario (cold shock), gradual drowning, where you are gasping due to breathing control loss, and inadvertently take water into your lungs, and hypothermia.
As the National Center for Cold Water Safety says, “…people who “never capsize” simply have not capsized yet.”
A final note, putting on a life jacket after falling into cold water is extremely challenging. There is no good reason not to have it on before you leave shore.
A final, final note, there is cold water protective clothing, such as wetsuits, which are skin-tight, and designed to keep you warm in cold water. That’s the kind of thing that cold-water surfers wear.
Ted Shapiro holds the Broadcast Seal of Approval from both the American Meteorological Society and the National Weather Association. An Alexandria, Va. native, he has been chief meteorologist at WAGM-TV since 2006. Email him at tshapiro@wagmtv.com.
