Cold water survival....^

Places, technique, kayaks, safety, the sea...
Post Reply
User avatar
MikeD
Posts: 147
Joined: Wed Sep 13, 2006 12:06 pm
Location: Denmark
Contact:

Cold water survival....^

Post by MikeD » Tue Nov 06, 2007 7:42 am

In the latest edition of Ocean Paddler on page 56, ther are some guidlines for the expected survival times in cold water:

21-27c 3-12h(EU) 3+(EST)
16-21c 2-7h(EU) 2-40(EST)
10-16c 1-2h(EU) 1-6(EST)
4-10c 30-60min(EU) 30-90min(EST)
0-4c 15-30min(EST) 30-90min(EST)
under 0c 15min(EU) 15-45min(EST)
(EU) = Exhaustion / Unconsciousness
(EST) = Expected survival time

What level of clothing does these guidlnes use as the starting point ?
What is the increase in survival times with a good longjohn, neoprene boots, hat, wind jacket etc.
If the victim is in a drysuit with good insulation, ie. underclothes of wool & insulation consisting of good quality fleece, how much longer does the victim in reality have ??

Any thoughts or comments are welcomed, the water temp over the next month or so will probably dip to under 5c in my local waters so I will be using a drysuit thankfully

Mike

YvonneB
Posts: 625
Joined: Mon Aug 28, 2006 5:07 pm
Location: Bath

Post by YvonneB » Tue Nov 06, 2007 7:50 am

A Canadian paddler I met once pointed out that although a drysuit and thermals will keep you alive in the waters of Newfoundland where he lives for quite a while, he expected to lose the use of his hands in 3 minutes. He had a very good roll.

Matt Rees
Posts: 142
Joined: Mon Jan 08, 2007 9:16 pm
Location: Cardiff

Post by Matt Rees » Tue Nov 06, 2007 8:36 am

I read somewhere that unprotected, below 10c, you get a minute per degree before incapacitation. Presumably those figures you quoted are allow for protection.

User avatar
runswick2000
Posts: 532
Joined: Thu Jun 16, 2005 3:17 pm
Location: swanage
Contact:

Post by runswick2000 » Tue Nov 06, 2007 12:32 pm

I believe that the figures quoted are based on a person entering the water wearing ordinary clothes.

No idea what you can add if wearing wetsuit or drysuit but it will be a lot!
Perhaps the greatest flaw in democracy is the idea that, if a majority of the population believes arrant nonsense, it somehow makes the nonsense true.

Lifeboat Scrapbook

Cameron
Posts: 337
Joined: Fri Dec 30, 2005 4:41 pm
Location: Cumbria

Post by Cameron » Tue Nov 06, 2007 1:55 pm

I think it is the US Coastguard that refers to the 50-50-50 rule.

After 50 min in water at 50 deg F (10C) 50% of people would have died (or words to that effect).

Very good point about loosing the use of your hands after 3 min YvonneB. Must remember to buy some neoprene gloves.

Cameron

User avatar
Mark R
Posts: 24087
Joined: Thu Jan 10, 2002 6:17 pm
Location: Dorset
Contact:

Post by Mark R » Tue Nov 06, 2007 4:57 pm

I don't know about those figures, but this is the bible on the subject ...
http://www.amazon.co.uk/Essentials-Sea- ... iversguide

I could be wrong, but I think one of the authors popped up during the Kate Middleton paddling programme.
Mark Rainsley
FACEBOOK

OGB
Posts: 94
Joined: Sat Oct 09, 2004 10:40 pm
Location: Moray Firth

Post by OGB » Tue Nov 06, 2007 9:09 pm

[quote="Cameron"]I think it is the US Coastguard that refers to the 50-50-50 rule.

After 50 min in water at 50 deg F (10C) 50% of people would have died (or words to that effect).

Having done a bit of personal experimentation on this subject, I think the question of "how long have you got before you die" supposes that you will survive after the initial dunking.

The primary threat used to be thought of as hypothermia, which is what most people dress for/worry about and what all (hmmm, most?) manufacturers of drysuits etc stress they'll help protect you against. Most victims "go under" far sooner than that. Cold Shock on initial immersion (gasp reflex = a good lungful of water) has killed at least one aquaintance of mine, who was otherwise a good swimmer and reported to have a reliable roll. Dry Drowning (inabilty to breath due to muscle spasm) can also get you, and this is all in the first 2 minutes.

If you survive that, and my personal research (brrrr!) confirms that you can desensitize yourself with practice under controlled conditions, then you're into what's called Short-Term Immersion. 2-30 minutes. This is the period when your muscles stop working, hands go like claws and you stop being able to swim. You can do little to help yourself but you will probably stay alive for another hour, perhaps 2 (at 10C -ish) if you keep still and go into the HELP position, although you'll be unconscious long before that. Hopefully your paddling buddies will have got you out of the water by then.

The above assumes reasonably sensible paddling clothing and no injuries. In a dry suit with reasonable insulation you'll survive a lot longer, but it's impossible to put a figure on this as individuals vary so much. A dry suit won't do anything to protect your extremities though, and you'll still lose the use of your hands pretty quickly, even with gloves.

Where does that leave us? Getting out of the water is obviously a priority - being wet but on the back deck of someone else's kayak is a lot better than being in the water. A rescue must be done quickly, before the swimmer loses the ability to help themselves. The risk of immediate incapacitation from Cold Shock etc may mean that your bombproof roll isn't, and you may not even be able to signal for help, so is your paddling group going to notice your upturned hull and get you upright before you expire? If you bail out, can you clip onto your boat somehow, before you lose the ability to hang on to it? If you lose the boat, what is going to keep you afloat - remember that treading water is going to lose a lot of body heat and you'll die more quickly....?

Oh, and assuming you are pulled out having got good and chilly you've got a 17% chance of croaking as a result of gravity pulling warm blood away from the core and replacing it with cold from the ends of your arms and legs. If you are still capable of speech, get your rescuers to keep you horizontal.

I guess that's enough to be going on with. I haven't read the Golden bible. Be grateful for a resume from someone who has.

User avatar
journeyman
Posts: 473
Joined: Sun Feb 11, 2007 9:57 pm
Location: South Wales
Contact:

Post by journeyman » Sun Nov 11, 2007 2:04 pm

Brief summary and useful reminder of cold water immersion that's been discussed recently on the forum (cold shock, HELP etc).

User avatar
Mark R
Posts: 24087
Joined: Thu Jan 10, 2002 6:17 pm
Location: Dorset
Contact:

Post by Mark R » Sun Nov 11, 2007 5:11 pm

OGB wrote:I haven't read the Golden bible. Be grateful for a resume from someone who has.
Well ... any book that can be summarised is a paragraph probably isn't worth reading. This one is.
Mark Rainsley
FACEBOOK

User avatar
journeyman
Posts: 473
Joined: Sun Feb 11, 2007 9:57 pm
Location: South Wales
Contact:

Post by journeyman » Sun Nov 11, 2007 8:14 pm

There is a fairly indepth analysis online here.
But the Bible as previously mentioned/linked must be Essentials of Sea Survival.
Some quite surprising information with references to real life occurances.
Certainly gives you a wake up call regarding immersion in cold water.
What stands out is that hypothermia, it seems, is not what claims the most lives.

User avatar
TechnoEngineer
Posts: 3292
Joined: Mon May 12, 2008 7:47 pm
Location: Berks, Hants, Essex

Re: Cold water survival....

Post by TechnoEngineer » Wed Feb 25, 2009 5:03 pm

Recently I've been reading this (I'm sure someone on this forum recommended it - though I can't find it):

Hypothermia, Frostbite and Other Cold Injuries: Prevention, Survival, Rescue and Treatment

Image

It is an excellent book, lots of information such as the ideal location on the body to apply heat, some information for medical practitioners that goes over your head, and some other interesting material such as how to escape from a sinking car and how to escape from a hole in ice.

Three things in particular that stood out for me:

1) the principle of convection - when you blow on something, you're forcing increased heat loss from a hot object by replacing the warm surroundings with cold. Frantically flapping your arms/legs about in cold water has a similar effect (better to adopt the HELP position and shiver).

2) feeding a shivering victim with sugary snacks to continue to fuel shivering

3) keeping a victim's body horizontal
XL-Burn-3 / Monstar / Kodiak / My Videos

burpblade
Posts: 25
Joined: Sun Jan 25, 2009 11:23 pm
Location: USA

Re: Cold water survival....^

Post by burpblade » Thu Feb 26, 2009 2:24 am

.....he expected to lose the use of his hands in 3 minutes.
Yup, a dry suit and under-layers will keep you going for hours, even at +5 eg C, but, having done a bit of professionally supervised bobbing around in cold water I agree that the hands can be a problem. A knowledge of the words and actions to "Underneath the spreading chestnut tree" will help though. ;-)

Ian_Montrose
Posts: 281
Joined: Tue Jun 17, 2008 9:16 am
Location: Montrose, East Scotland

Re:

Post by Ian_Montrose » Sun Mar 01, 2009 9:16 pm

Mark R wrote:
OGB wrote:I haven't read the Golden bible. Be grateful for a resume from someone who has.
Well ... any book that can be summarised is a paragraph probably isn't worth reading. This one is.
I'm currently about 2/3rds of the way through Essentials of Sea Survival and would also recommend it. It's fairly academic in its approach and I don't feel qualified to summarise it considering the importance of the subject matter, but It's opened my eyes to the variety of threats quite considerably. I would suggest that anyone who thinks a drysuit is the be-all and end-all of cold water survival makes a point of reading this book.

Post Reply