DIR and Ice Diving

[vioch]

Neither GUE, nor UTD have Ice diving procedures.

Diver connected with a rope to the tender on the surface is tought by most agencies.


How do DIR divers perform Ice dives?

 

[ppo2_diver]

There is not official "DIR" ice diving. However, most I've talked to deploy a shot line, then run like a cave or wreck environment. I'm not aware of an agency that doesn't require the diver-attached line.

 

[rjack321]

Typically as if it were a well lit cave - running line but minus a tether.

However penetrations are generally shorter, deco is avoided (not worth it) and current is now considered just not worth it as well. Short ice dives are good training exercises in the off season but longer and/or more committing dives done in the ice season rapidly exceed the tolerances of the gear and the value of the dive when it can also be done under friendlier conditions 6 months later.

These guidelines were roughly (& painfully) worked out by the Ontario GUE contingent.

 

[captndale]

Safe ice diving can be done using either the ice diving protocols established through the years by northern regional divers or using cave/wreck protocols. There are, however, two major problems with cave/wreck protocols:

There tend to be few, if any, tie points in an ice environment. The underside of the ice is smooth, so a diver would have to use screws to tie off there. Installing or removing ice screws would be difficult and time consuming. Rocks, trash, tree limbs and the like might be available on the bottom to be used for tie points but not always, and the bottom is usually covered with fine silt. Normal cave line is negatively buoyant, so dragging it across the bottom will raise silt. Small diameter floating poly line would be a better choice but it still must be tied at frequent intervals to reduce the probability of entanglement.

Using cave/wreck line techniques for ice diving eliminates the ability of the divers to communicate with the surface. A diver on a stout line can even be pulled back by his tender in an emergency. Catastrophic equipment failures are so common in ice diving as to be expected. They must be planned for.

 

[fppf]

Treating an ice dive like a cave or wreck dive can be hazardous to your life.

Try doing a lost line drill when you can go for a mile in either direction.

 

[vioch]

Why do you assume a mile? With proper line awareness safety spool should be more than enough for lost line drill.

 

[rjack321]

Rocks, trash, tree limbs and the like might be available on the bottom to be used for tie points but not always, and the bottom is usually covered with fine silt. Normal cave line is negatively buoyant, so dragging it across the bottom will raise silt. Small diameter floating poly line would be a better choice but it still must be tied at frequent intervals to reduce the probability of entanglement.

Most folks were consider the slack line dragging around a hazard unto itself. If the bottom is bereft of tie-offs people usually bring PVC stakes.

Using cave/wreck line techniques for ice diving eliminates the ability of the divers to communicate with the surface. A diver on a stout line can even be pulled back by his tender in an emergency. Catastrophic equipment failures are so common in ice diving as to be expected. They must be planned for.

The DIR solution to catastrophic gear failures is to bring doubles at a minimum. Doubles as backup and breathing a stage is also common. Good technique and breathing patterns minimize free flow failures - as well as using quality very low dewpoint gas.

Getting hauled back to the surface is not really an appealing contingency plan for cave and technical divers - even when they are doing less committing recreational dives.

 

[rjack321]

Try doing a lost line drill when you can go for a mile in either direction.

Dive like the PSD guys, stick to a tether, or pick a more benign site where this isn't an issue.

My untethered ice dives (a whopping 3) were done in a quarry that is not very deep, bounded, and virtually silt free. Kinda like a "well lite cave"

The current DIR solution is to back off on the dive parameters until its within the scope of the gear and conditions under the ice to avoid the dope on a rope factor and substitute shallow practice & fun.

Aggressive ice diving was tried and its now viewed as "not worth it". Search TDS for "Kinghorn Fatality" if you want some history.

 

[elan]

Yeah that particular quarry is very small and can be traversed within 10-15 mins range. That makes a lot of difference.

I think even if completely disregard free flow managing and breath out of the flowing reg you can still make to the exit point. Mind if you have the flowing stage you can modulate the valve and exit safe.

Another point to consider is that cave line is very thin and prone to wearing off easier when it freezes up on the surface.


Ice Diving Operations is a good book to start with regarding the safety and protocols of ICE Diving.

 

[fppf]

I'm just pointing out when under the ice in most cases is not like being in a tube or passageway. Most caves and wrecks give you very small cross sectional areas to search, where under the ice your in open water. Even our local DIR instructor teaches the diver/tender method.