sean, I see teathers as a huge possible risk of entangle ment and limit the dive more than necessary. Risk management.. can be in the eye of the beholder. I believe that teathering is nessesary for commercial work SAR work and moving water diving. I also believe that Ice diving should never be done in moving water. As none of the lakes that we ice dive have currents then teathers seem to be not needed. by using a reel as in cave/wreck diving you have a continuous line to the surfaceand thus back to the entrance hole. you spoke of zero vis. Usually (at least the sites we ice dive (ALBERTA LAKES)) the visibility is much much better in the winter time especially on a brite and sunny day. We take lights but have never had to use them. As fare as following a small diameter line in open water as oppossed to a confined space (just try closing your eyes and reeling it in)its not difficult. I also believe that the diver is more efficient at layin line and taking it up than the tender. Lets face it a reel isn't that hard to run. As far as communication over the last few years we have been using AGA masks with full com gear(keeps the face much warmer and allows for much better communication than rope pulls if you so desire. The ice should always be cut in one piece and pushed under the ice. The key thing is to anchor the triangle at a minimum of two points. this prevents the ice from moving into the hole by itself but also allows one to responsible close the hole(and still mark it properly)after the dive is done As far as surface personal go Keeping the hole free of ice is a comfort thing. in the time of an ice dive the ice forming in the hole is so minimal as to negligable. tho keep people away from the hole as a diver you should ensure that it is adaquately marked. To assist entry and exit. a rope ladder works great as well(i have entered many small cenotes via a ladder without surface support.) I feel that there are many improvements that can be made in the ice diving communities without compromising safety. By using common sence ant the proper gear and gas management rules there should never be any problems unless it is with trhe divers ability ar previous training safe diving STEVE > >Steve, first off, do you mean to say that you dive with only the two of you? (ie. no surface >support?) Surface support is a necessary part of any ice dive, although I don't think you need to >have five people, necessarily. It is comforting to know that the hole will be kept clear for your >return, and that you have some assistance in getting out of the water and your gear, especially on >long dives when you want to reduce the risk of a DCS hit. Tethers are a method of risk management >based on the possible lack of visibility. Most ice diving is in open water as opposed to confined >passages, as would be encountered in a cave or wreck. Imagine yourself diving under ice in zero >vis and finding your way to the surface (and the hole) in open water by a small diameter free >floating line. This scenario is further complicated by currents or line entanglements. Using a >tether provides you with line pull communication with the surface, as well as a guide back to the >hole that is easy to follow. As well, you don't have to deal with laying line or taking it in >during the dive, as your tender does this for you. There is no need for multiple tender lines, as >each diver should be connected to the lead diver by a buddy line, and may communicate with the same >line pull signals. I remember a report of two ice divers who cut their hole in a single piece and >couldn't lift it out so they pushed it down and underneath the adjacent ice, then went diving >without surface support. During the course of their dive the piece shifted and plugged up the >hole. There is no reason for events like this to occur. > >-Sean > > >On Fri, 09 Jan 1998 11:45:42 PST, Steve Schinke wrote: > >>i recently had a debate about the correct way to ice dive and i thought >>i would see what this lists reaction was. We live in northwestern >>canada and have ice coverd lakes for about eight months of the year so >>unless one has alot of travel dollars you have to leard to ice dive to >>get wet. >> >>This person was in support of some of the large diving factions >>standards involving a five person team requiring the divers to be >>teathered and a teathered safety diver plus two line tenders. >> >>my argument was that this seemed to be a little over excessive. I >>argued that Ice should be dove like any other overhead environment >>using reels, and gas management principles, and that teathering >>unnesessary. The divers should be competant enough with there skills >>that being roped together and to the surface is ridiculous.(perhaps >>eight dives doesn't classify you as a competent advanced diver.....) >> >>usually the way my buddy and i dive is with reels and ice screws in a >>two man team using thirds. We also carry min of two lights although it >>is usually unnesesary to use them. the only drawback is thaqt cutting >>the hole takes more effort. I was wondering how other people dove ice >>as our tech community is rather isolated and small up here. >> >>STEVE SCHINKE >> >>______________________________________________________ >>Get Your Private, Free Email at http://www.hotmail.com >>-- >>Send mail for the `techdiver' mailing list to `techdiver@aquanaut.com'. >>Send subscribe/unsubscribe requests to `techdiver-request@aquanaut.com'. >> > > >-- >Send mail for the `techdiver' mailing list to `techdiver@aquanaut.com'. >Send subscribe/unsubscribe requests to `techdiver-request@aquanaut.com'. > ______________________________________________________ Get Your Private, Free Email at http://www.hotmail.com -- Send mail for the `techdiver' mailing list to `techdiver@aquanaut.com'. Send subscribe/unsubscribe requests to `techdiver-request@aquanaut.com'.
Navigate by Author:
[Previous]
[Next]
[Author Search Index]
Navigate by Subject:
[Previous]
[Next]
[Subject Search Index]
[Send Reply] [Send Message with New Topic]
[Search Selection] [Mailing List Home] [Home]