Coldest dive sites in USA

[DA Aquamaster]

Perhaps I was unclear, let me address it from the opposite side. I've been on many expeditions into the Arctic, water does not get any colder than it is there, I have never seen regulators that were properly handled freeflow. Every case of freeflow that we experienced could be quickly and easily traced to a clear error on the part of the diver involved, typically this was either having fresh water in the regulator as a result of improper washing, or breathing off the regulator before it was submerged.

We had a real comedy of errors once when an entire team of divers (who had been trained to do a giant stride with their regulators in their mouth, and would not listen) jumped off the side of the ship, and froze up almost instantly. They had to scrub their planned dive, and when ship time is running $12,000.00 a day that's a major error.

I think we agree on that - good technique always matters.

My favorite is a subset of OW divers who dutifully test their regs and inflate their BC's before jumping in to ver y cold water - ensuring the first stage cools to well below freezing before they even hit the water. You can't tell them anything different as the reg testing and BC filling process is practically engraved on the inside of their skulls.

Good cold water regulator technique in general:

But first the basic problem - The air expanding from tank pressure to intermediate pressure in the first stage has to take on a great deal of energy to get the molecules involved moving faster and it does this by drawing heat from the reg. The reg in turn has to draw heat from the surrounding water to stay above freezing. Heat transfer is much lesse efficient in air - on the order of 80 times less efficient.

So...

1. Don't test, breathe off of or in any way use the reg (fill a BC, dry suit, etc) until the first stage is fully submerged.

2. Don't over breathe the reg or put yourself in any high exertion situtations when ice diving.

3. Don't inhale and inflate at the same time.

4. If you inflate your BC, dry suit, lift bag, etc, do so in very small bursts with time in between to let the regulator draw heat from the surrounding water to rewarm itself. (ie: plan ahead and make small corrections, not large ones.

5. Do not let a freeflow occur (giant stride entry, letting the reg fall out of your mouth, bumping the octo purge button, etc.)

 

[David_57]

Yes I agree with DA 100% have to always consider the possibility of freeflow but should be able to greatly reduce the chance of this happening with good technique training and the right equipment.

But still stand by what I said before greater chance of freeflow in -2c than +5C water