Cool and Cold Water MOBs--It Seems Like Even Easy Recoveries Fail

[thinwater]

Without question, a dry suit is the safe answer (a wetsuit in merely cool water). But above about 10-15C air temperature, depending on whether it's raining and depending on activity level, they get a little steamy. In spring weather conditions (meaning 20-25C air with 5-15C water here--could be summer in much of the UK) it would be nice to wear something like a dinghy suit, with tight wrist, waist, and neck seals. Perhaps that's not so different than a dry suit, but it certainly easier to put on and take off, and to adjust layers. That might be the critical difference.

Remember, I'm not talking dinghies, with continuous splash. In water that cold I would be wearing a wetsuit or dry suit. I'm talking about larger boats that are probably dry much of the time. In a way, that makes the problem worse; warm air and cold water. A dry suit is only pleasant if it's really cold or if there is rain or spray on the suit.

Another thought is soft shells with effective wrist and neck seals. I once went for a swim wearing a softshell (Windblocker fleece) in 5C water. While extremely unpleasant, that neck seal made an important difference in terms of the shock. I was in the water for about five minutes (seemed much longer) but in fact, did not even chill the point where I was shivering. Fortunately, I was slightly overheated when I went in, so I doubt my body temperature had a chance to go measurably below normal.

Thoughts?

 

[Kurrawong_Kid]

Thankfully, your instructor did not need to give evidence at a Coroner's inquiry followed by an appearance at Crown Court on a manslaughter charge.

More likely 50 years ago a Coroner would have given an Accidental Death verdict with an observation that clothing should be developed for safer winter sailing. The H&S blame culture was in its infancy then. Not saying H&S is a bad thing, only that 50 years ago times were different.

 

[Kukri]

I’m in the 60-70 bracket and I think I must get into the habit of wearing my drysuit routinely from October to June.

In fact I am starting to get into the habit of putting it on and taking it off at home, a couple of times a week, so I can do it quicker and faster.

 

[thinwater]

... I might be very wrong - but (assuming reasonable swimmers, and happy in water) throw a 10 year old head first into cold water and they will come up laughing, throw a 50 year old in the same way and he will struggle....

Jonathan

Since heart stress is one factor, intuitively this feels right, but I haven't found any information relating cold water shock to age. Just scattered anecdotes. If anyone comes across something, please share.

I'm more experienced than I used to be and can sail more efficiently. I remain quite active. But I'm under no illusions that I am tough as I once was.

 

[bikedaft]

Read sea survival by tipton and goldmann - us and uk navy and others' research into cold water 'shock'

We can acclimatise to very cold water so that we do not involuntarily gasp water in our airway/lungs when we go in head first (good point btw)

Tipton/goldman suggest yearly - personally i need to do it 6-9 monthly.

Even a dry suit will not stop you involuntarily gasping when your head is underwater.

Also consider inverted dinghies or helo's where you need to be able to hold your breath

 

[thinwater]

... Even a dry suit will not stop you involuntarily gasping when your head is underwater.

Also consider inverted dinghies or helo's where you need to be able to hold your breath

I will read that.

I can't agree with the drysuit comment, having done just that many times. I was wearing a hat, of course, but not generally a hood. The same could be said of countless kayakers. I suppose we are getting down to individual tenancies. A slap in the face, but not cause to gasp if braced for it. Of course, I acclimatize, as you call it, may times a year.

 

[lw395]

Search for Cold Water Shock. It is SUDDEN exposure to cold water that is the issue.
You can be physically fit, Best swimmer. Makes no difference.

The same person, gradually exposed to the same degree of cold will be fine.

An auto lifejacket that works is KEY. That means REGULARLY checking the cylinder is fitted correctly.

Foam will be PITA

Not convinced a suit will be the answer. There will always be a chance a zip is undone etc.

Keeping the person above the water gives them time to get past the initial shock which is where it all goes wrong... if your intial response is to breath in the water in shock you are screwed.

Is a certain level of permanent foam buoyancy really out of the equestion?
Dinghy sailors, canoeists, board sailors, kite surfers seem to manage to be fairly agile compared to your typical yacht crew, while wearing a 50N buoyancy aid. They also fall into cold (ish) water fairly often with a low level of tragedy.
I've worn dinghy buoyancy aids racing keelboats. When everything goes wrong, there is a certain comfort in being able to trust something with no moving parts.

Obviously a 50N buoyancy aid is not the full shiulling for a 'Titanic re-enactment', but for falling off a race boat that's competent to turn around and pick you up in short order, maybe it's better than something which has negative buoyancy until/unless it inflates?
Maybe 50N of permanent foam and 125N of CO2 might work?

 

[capnsensible]

Here we go again. Seems like a right time to repost this stuff thats been knocking around now for a few years:

http://www.coldwaterbootcamp.com/pages/1_10_60v2.html

Lots and lots of learny there for anyone interested in safety for you and your crew.

Enjoy. :encouragement:

 

[capnsensible]

 

[AntarcticPilot]

Worth bearing in mind that the gasp reflex is just that - a reflex. You can't suppress it any more than you can suppress the jerk of your leg when the doctor hits your knee, especially when it happens unexpectedly - and by definition, a MOB is unexpected when it happens for real. You MIGHT be able to control it if you are expecting the shock, as is the case in any training situation, but if it happens without notice - as in a real emergency - you can't.

 

[AntarcticPilot]

Without question, a dry suit is the safe answer (a wetsuit in merely cool water). But above about 10-15C air temperature, depending on whether it's raining and depending on activity level, they get a little steamy. In spring weather conditions (meaning 20-25C air with 5-15C water here--could be summer in much of the UK) it would be nice to wear something like a dinghy suit, with tight wrist, waist, and neck seals. Perhaps that's not so different than a dry suit, but it certainly easier to put on and take off, and to adjust layers. That might be the critical difference.

When in Antarctica it was mandatory to wear a full survival suit when in small craft (my avatar shows me in such a suit!). I can assure you that even in temperatures around zero, they are extremely hot and uncomfortable, precluding any serious physical activity! When the avatar photo was taken, mine was undone down to the waist (I was ashore), and even so I was far too hot! And I was about 100m or less from a) sea with lots of floating ice and b) a glacier!

 

[bikedaft]

Worth bearing in mind that the gasp reflex is just that - a reflex. You can't suppress it any more than you can suppress the jerk of your leg when the doctor hits your knee, especially when it happens unexpectedly - and by definition, a MOB is unexpected when it happens for real. You MIGHT be able to control it if you are expecting the shock, as is the case in any training situation, but if it happens without notice - as in a real emergency - you can't.

yes you can - if you have had your head underwater within the last year (tipton and goldman) or 6 months in my case (i must be soft!)

i don't think its as absolute as that tho - the colder the water, and the longer since you last had you head under the water, and was your "training" dip in as cold water etc etc

a wetsuit hood etc all helps in the real situation

i do check if i can jump in and hold my breath/not gasp in cold water, on entry to water. must try head first, but usually go a fair way underwater just jumping from deck or pulpit

 

[thinwater]

When in Antarctica it was mandatory to wear a full survival suit when in small craft (my avatar shows me in such a suit!). I can assure you that even in temperatures around zero, they are extremely hot and uncomfortable, precluding any serious physical activity! When the avatar photo was taken, mine was undone down to the waist (I was ashore), and even so I was far too hot! And I was about 100m or less from a) sea with lots of floating ice and b) a glacier!

Curious about the survival suit. I've spent 6-hours in 0C water (there was ice) in a standard dry suit as part of a test, with no drop in body temperature. I was just bored. So long as the air temperature was below ~ 5C I was fine for normal sailing activity. I was fine up to about 10C with fewer layers, which would still comfortable in 0C water for 30 minutes and safe for FAR longer. In other words, overheating was not a serious problem as long as it was reasonably cool. Heck, people kayak in drysuits (hard work) in 5-10C air temperatures all the time.

Water doesn't get colder than 0C, so I'm not sure why more insulation was needed. If you needed to open the suit to work, then function was compromised. Something doesn't make sense to me.

 

[AntarcticPilot]

Curious about the survival suit. I've spent 6-hours in 0C water (there was ice) in a standard dry suit as part of a test, with no drop in body temperature. I was just bored. So long as the air temperature was below ~ 5C I was fine for normal sailing activity. I was fine up to about 10C with fewer layers, which would still comfortable in 0C water for 30 minutes and safe for FAR longer. In other words, overheating was not a serious problem as long as it was reasonably cool. Heck, people kayak in drysuits (hard work) in 5-10C air temperatures all the time. Water doesn't get colder than 0C, so I'm not sure why more insulation was needed. If you needed to open the suit to work, then function was compromised. Something doesn't make sense to me.

The water temperature is only about -2 (remember it's salt water) but the air temperature may be much lower in Antarctica. Even in summer, -10 would be quite usual, and far lower in winter. These were also flotation suits; no separate lifejacket was required. The suits were totally self-contained, with integrated boots. They weren't designed for any form of activity and would be totally unsuitable for sailing wear.

 

[capnsensible]

Heres one thats been translated into Murican.