Under ice diving?

[shiney]

It’s interesting to read about divers who want to dive under the ice using cave dive or modified cave diving rules. I am only a cavern diver with hopes of becoming a cave diver soon. I have been diving in ice cold water for many years and have logged hundred of dives in winter conditions. The idea of going under the ice with a cave dive reel and heading off into the deep blue water really scares me. When you enter the water with only a dive real and head away from the hole it does not take very long to loose sight of the hole. Once you loose sight of the hole you your life is hanging on the hopes that that one line does not break.
The one thing I did learn from the cave divers I talked to in Cave country in Florida is that they have as many redundant safety features as possible. If you enter the water and dive under the ice you better be tethered to the hole and have at the very lest one dive team at the surface ready to help you if you end up in trouble. I might entertain the idea of using a reel, but I would also insist that my buddy also had one. Unlike diving in a cave that actually has some sort of reference back to the surface. Diving under the ice offers little of no reference back to the hole. Once you get a very short distance from the hole and look towards the surface everything looks the same. If you get in trouble under the ice and don't have a solid plan all you have is a guess which way is back to the little 10 foot triangle cut in the ice. I won't use ice diving training for cave diving don't use cave diving training for ice diving.

This is one of the reasons we wanted to have a dialogue on. What should the base line be for executing a safe dive using cave techniques (environmental, training)? We have had a couple of deaths over the years, and with access to training becoming easier, there seems to be more and more divers wanting to ice dive. There are really no hard and fast rules you can use on all ice dives. I know of more people who have free flow issues in fresh water at 32-34F then I know of divers doing dives in salt water at 28-31F.

The quarry we use has fantastic viz, if you are somewhat familiar with it and you cut the hole in a logical place. You can use the UW terrain to navigate to the hole. The water is a balmy 37 which doesn't seem to lend itself to causing free flows easily. Modified cave techniques works very well in this environment.

On the other hand, in a completely ice covered river, where current & debris may cause a line to be cut, doing a dive using cave technique is stupid, and the diver should probably be tethered.

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-not exceed a depth of 150 feet on any dive and not exceed a depth of 100 feet on most dives based on certain criteria. ***

-only dive when a suit heater is available. ...................

I personally wont do a deco dive when the water is that cold, suit heater or not. I do not feel like deciding if I should bail on my deco due to hypothermia, if I ever got a suit flood . Furthermore, though your core will be warm with a suit heater what about the off gassing in the extremities?

We choose to keep our depths relatively shallow, as we have concerns about adiabatic cooling at depth where there is more flow going through your reg...possibly causing free flows again.