What's the Survival Time for UK waters in Drysuit in Summer?

[Helen F H]

Ok, interesting question.

What is the predicted survival time in UK waters for a diver in standard kit (drysuit not wetsuit) during the summer and during the winter?

I can recall reading this somewhere, but cant find the article or the thread.

Cheers people!

[onthetrain]

there was an article on this in one of the diving mags last month

[Twinset & Wing]

winter depending on thermal underwear about 3 hours from memory in winter
about 5 in summer

In normal clothes or waterproofs it is about 15-30 mins in winter and about an 1-1.5 hours in summer

Puts it into perspective doesn't it

[Sipadan]

Originally Posted by Twinset & Wing

winter depending on thermal underwear about 3 hours from memory in winter about 5 in summer

Now that does make you think, I assumed it would be a lot longer in a drysuit.

[Bogwoppit]

I think I remember from my Sea Survival training that you had approx 4 minutes in the North Sea in the winter before you would be dead from the cold which would cause shock and convulsions quickly followed by drowning. This is of course only without the correct exposure equipment. Nice eh..

[Scuby]

Originally Posted by Twinset & Wing

winter depending on thermal underwear about 3 hours from memory in winter
about 5 in summer

Surely that can't be right, not for drysuits at least. I kow people on rebreathers have done 3 hour dives in Stoney in the winter. Probably not the warmest end of a dive, but certainly much more left in them in terms of survival...
And in the summer people play in the sea for hours on end with just shorts and don't get cold, so with my fluffy undersuit and drysuit i'm sure i'd last significantly longer than 5 hours...

David

[Sipadan]

Originally Posted by Scuby

Surely that can't be right, not for drysuits at least. I kow people on rebreathers have done 3 hour dives in Stoney in the winter.

I was kinda thinking that too.

???

[Helen F H]

I remember the story of two guys who were lost off the farnes for 24 hours when i was learning to dive, but it may well have been boswelox.

I think part of it is keeping active while underwater, i always seem to get cold fairly quick if i am hanging about fizzing off - if you are sat on the surface waiting for a boat you are not moving and probably not mentally prepared for it hence fare worse than if you plan to be in the water for 4 hours.

[Mick F]

One diver over here spent 9 hours adrift off North Donegal last year (drysuit, dumped kit) and survived, albeit on the edges of severe hypothermia, so those figures do seem shortish.

Also, wouldn't it depend on the rate of heat loss from the individual. I know that the rate of loss is dependant on several individual based factors including physical size, respiration rate, and lung capacity. These factors are in addition to the external factors such as clothing etc.

Hypothermia is defined as a core temperature of less than 35C, and moderate hypothermia which I think is less than about 33C is enough to cause sufficient loss of muscular control to induce drowning.

So how long would it take to drop the 4°C of core temperature to create the right conditions for drowning?

[Janos]

I thought that there were oil rig workers who were picked up in the North Sea after longer times then that. Sadly, that's when they found out about immersion shock, so remember to pick them up out of the water horizontally

Janos