hypothermia table

-- Last Updated: May-18-08 5:21 PM EST --

hi folks ...rather than post replys on various threads about dry suits and cold water wear, i'll post it on it's own thread. this is the only link i could google up fer hypothermia tables. As has been said here..dress for the water , not the air.
PS: I've read a few online articles that stated a few people have drowned b4 swimming 100 ft in water under 50F. So the caveat is: going cheap won't save your life in cold water.

http://www.fintalk.com/resources/boats/hypothermia.html

"going cheap won’t save your life …“
in cold water”









But it will save you money!

Not When You Factor In…
…the cost of a funeral.

a problem with tables
is that it really doesn’t tell you how long your hands will work, how well your head or breathing will work, simply that at X range of minutes a slab of warm meat will get cold. If your hands lose substantial strength and dexterity in five minutes but the chart says you will be exhausted in 30 minutes then five minutes is the time you’ve got, not 30. If an unprottected head gets vertigo in 20 seconds of immersion in very cold water then you have 20 seconds, not 30 minutes.

how about this
1/10/1 rule.



1 minute to control your breathing, 10 minutes of useful time with your hands, 1 hour till near death.



assuming near freezing water. a hypothermia researcher devised it and thinks it’s the the end all be all.

re: hypothermia
hi again all…i think most ppl here are aware that the tables stated are not absolute and vary and assume a lot of things, i think ppl are smart enough to read between the lines and understand out of that XX minutes in XX temp water…you really only have a very small percentage of useful time to rescue yourself or someone else b4 hypothermia sets in. I think the 1 good thing I seen in replies is having appropiate, effective head covering also. safe paddling folks

that makes sense
except I’d apply that to 50 degree water. If I stick my bare hands in 50 degree water they’re not doing too well after a couple minutes. I did an immersion in 39degree water for twenty minutes using the equivalent of 5mm wetsuit with hood, gloves and drytop. My arms had the equivalent of 2mm neoprene in various layers of fuzzy rubber, skin shirts and dry top. While my core and extremities were fine the very cold water on forearms where water entered the dry top through the bottom resulted in significant loss of strength,but without being aware of it until I did some basic rescues.

head gear make a BIG difference
But reading between the lines isn’t experience.



People are smart enough to make assumptions and hypothesize scenarios before heading out on a recreational paddle in COLD water but not that many are smart enough to actually go out into that water and test their responses IN that water BEFORE playing in it.



I was assisting an ACA IDW five years ago that was in 48degree water and air in flat water. All of the participants are what you’d call intermediate to experienced paddlers. About 1/4 had inadequate head gear and a couple disregarded the need for head gear in a filmed test on paddle technique, bracing and rolling. To say nothing of the number who simply didn’t haver their pfds on tight enough for being in the water.



One fellow finished up his demonstration of paddling techniques with three rolls. I offered him one of my beanies or hoods and he said no thanks. He had a few years of whitewater experience and was a big strong guy with the capacity to generate LOTS of calories. Except we were in a pretty low calorie environment with short distance paddling, waiting, etc.

He did everything great then did the three rolls, then tried a hand roll for fun and showing off. Except he couldn’t pull it off and wet-exited, as he was getting the spins. After that he walked like a drunk getting out on shore 20’ away.



He’d never experienced the spins like that. It wasn’t the rolling, it was the cold water flushing into his head and ear canal.

I am with the others…
I agree with the others - the hypothermia table is definitely not perfect, and barely serves as a guideline. Someone trying to figure out what to wear will likely use the upper end numbers to support their decisions to wear jeans and a t-shirt on 50 degree water, figuring they will stay close enough to shore to swim in the time allowed.



But, once you start swimming, you take yourself off any chance of being on the upper end of the limit, as heat loss is much greater when swimming than when staying still.

exactly
the graph is useful for rescuers guessing whether they’re rescueing a person or a hunk of cold meat. It’s not useful for a paddler determining THEIR survival times where survival is dependant on THEIR skills.

Not much use in knowing you got 20 more minutes of lucidity because you didn’t know you didn’t have more than 10minutes of functioning dexterity.