Cold in the Water - What you SHOULD know!

So, my sharing of DAN's article wasn't as educational as I hoped. I do, however, stand by my first statement! :chuckle:

Jax:

I told you that stuff wasn't good for you! :scorned:


See how well you score on DAN's new safety quiz: Alert Diver | Thermal Stress and Diving Quiz

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So now, I invite everyone to come in and post a fact about cold water diving, or cold weather injuries as could be related to diving, and let's share the important knowledge we SHOULD know.


FACT: Hypothermia can happen before you recognize it, if you are not paying attention.

Know these symptoms: ( from: HowStuffWorks "How Hypothermia Happens" )

• Mild Hypothermia: shivering, goose bumps, difficulty with complex motor skills
• Moderate Hypothermia: violent shivering, sluggish, speech problems, difficulty with fine motor skills
• Severe Hypothermia: rigid muscles, dazed, shivering has stopped, blue skin, erratic heart beat, unconscious

If severe hypothermia sets in, complications can include coma and even death. Other cold weather injuries are also associated with hypothermia, such as frostbite, chilblains (ulcers on the toes) and trench foot (a foot infection).

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Well jax, having 8 to 1o drinks and going out to pull crab traps and falling in with just sweats on and in 10 mins going across the water when air temp 48 and water temp 48, Moderate Hypothermia set in and I had a hard time swiping keycard to get in clubhouse to jump in pool, so jumped in hot shower.

In summer I would say I get mild hypo after dive in wet suit from zodiac, once close to land it warms and once boat is on trailer and over at wash station while washing in sun it goes away, this happens from april through september.

Some deco dives my hands get gold in thermo cline, two days ago the shallows was 40 where in past 20' was 46. yesterday 14 min deco and hands not that cold 45 at deco depth.

It has been many years since shivering while diving, trying to remember the dives, just has not set in yet to explain.

Can't take it with the iPad but from question one it looks simple.

Shivering after getting out of the water was pretty normal in Northern California where I learned to dive in the early 1960s. Shivering while in the water, mostly in deep-sea rigs on Helium, was also pretty common while in the Navy before hot water suits. It is still pretty common in commercial diving in many areas of the world. About the only thing that was done to compensate was to bump the diver up on the decompression table (time or depth) — which extended the misery.

This is not to minimize the risks of hypothermia in any way, but I have not seen any negative effects beyond poor work performance. However, poor work performance is not only tactile, but also mental. A diver on the end of a hose and in communications with a dive supervisor in a heated gas shack is at far less risk of doing something stupid (hypothermia induced) than a Scuba diver.

You also must remember that the effects of hypothermia are much more serious and dangerous to people who aren’t in good physical condition, older (like me now), and aren’t acclimatized to cold water. When it comes to recreational diving, hyperthermia should never happen unless there is a catastrophic event — drysuit failure, lost at sea, etc. By definition, recreational diving is fun and being cold isn’t.

• Mild Hypothermia: shivering, goose bumps, difficulty with complex motor skills
• Moderate Hypothermia: violent shivering, sluggish, speech problems, difficulty with fine motor skills
• Severe Hypothermia: rigid muscles, dazed, shivering has stopped, blue skin, erratic heart beat, unconscious

If severe hypothermia sets in, complications can include coma and even death. Other cold weather injuries are also associated with hypothermia, such as frostbite, chilblains (ulcers on the toes) and trench foot (a foot infection).

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:shocked2:Awesome.

I appear to have Moderate Hypothermia after every dive I've ever done!

Remember that hypothermia, in addition to making you clumsy and stupid, also has implications for decompression. Don't push limits in cold water!

You have to use logic. If you're shivering a little doing a shallow shore dive, continuing the dive will most likely be fine. You have to know your own body and what becomes unacceptibly unpleasant. If it weren't for the obvious dangers of being underwater it would be the same as being topside and too cold. A major concern is what happens after the dive. Do you plan a 2nd dive? Is it 80F and sunny or 40 and cold? Is there a heater (or even a car) on board or nearby? Can you get changed to dry clothes quickly and out of the wind? Hypothermia can progress after the dive as well.

Hmmm, I am not convinced by the quizzes answer to question 13.

"The lower thermal conductivity of argon provides a theoretical advantage over air as a drysuit inflation gas in cold water. The effectiveness is probably chiefly limited, however, by the mobility of the gas bubble within the suit, since the gas rises to the highest point instead of maintaining a uniform insulating layer throughout the suit. Secondarily, the expense of argon may limit suit flushing to eliminate inert gas from the suit. Practically, argon may provide a small improvement in thermal protection, but this would likely only be meaningful for extremely long diving exposures."

Could one not extend this to argue,
"The lower thermal conductivity of AIR provides a theoretical advantage over Helium as a drysuit inflation gas in cold water. The effectiveness is probably chiefly limited, however, by the mobility of the gas bubble within the suit, since the gas rises to the highest point instead of maintaining a uniform insulating layer throughout the suit. [-]Secondarily, the expense of argon may limit suit flushing to eliminate inert gas from the suit.[/-] Practically, AIR may provide a small improvement in thermal protection, but this would likely only be meaningful for extremely long diving exposures."

Experience tells me otherwise. A while back I was running a series of almost identical profiles. I filled my suit with 55% He on two of them. I was shivering for the last 40mins of deco. Attached a drysuit inflation tank with air and no shivering for the remaining 4 dives.

Also, their secondary argument is that Argon doesn't work because I am not prepared to flush my suit when I use it. Kind of like arguing that helium doesn't work for deep dives because the cost prevents me from breathing it? If you are going to pay for it, you might as well use it properly.

Understand that it says violent shivering. One looks like a mild epileptic seizure. If you cannot control the shiver, get out of the stinking water.

What TSandM said about "clumsy and stupid" -- if you are super cold, you may fall into "follow the pack" mentality, and loose more and more of the brain's agility. Next thing you know, you stop shivering, you're kind of numb, no one can tell you're blue underwater . . . unconsciousness can follow quietly.

Stealing this also from the other thread:

This article from 2007 pretty much sums up the cold water issues. This young women died when her overly large wetsuit allowed too much circulation of 7^o - 9^o C [45^o - 48^o F] water. The hypothermia slowed her down, then she went unconscious and drowned. THIS is important data, not the technical names of cold water terms.


Diver died because her suit was too big | Mail Online[/QUOTE]

BTW, guys, please remember this is in the Basic forum . . .

How many people know that hypothermia can happen in 85^oF water? All it needs is for your core temperature to drop to 95^oF . . .