Triggers of Dive Accidents

[LiveBait]

If the BOWD stays anywhere near the limits of her training, she'll max out at 60 feet or so and even on air she will have a long time to look around -- PER THE NDLs. But, if she is in the tropics, she'll probably be breathing off an 80 (that's what, 12 L in the rest of the world?) with a SAC of 0.6 (and if male, 0.8). Now IF she has followed her training, she has done the basic calculation (here I'm using the PADI RDP) and found she can stay down for 55 minutes so that is her plan -- afterall, the shop is giving me a tank and shouldn't I be allowed to dive for the whole time? Ooops, at a SAC of 0.6 (which is being very generous for a new diver) she runs out of air at 42 minutes while her boyfriend runs out at 32 minutes.

That is exactly what I was trying to say!! Good job.

I think almost everyone here thinks more quality training is needed. The only problem is what should that be...

 

[Jax]

spoolin wrote
But it appears your assumption is just flat out wrong -- at least IF the DAN stats are anywhere near accurate.

I admit I don't know much about DCS, why it occurs for example, but I do know that there does appear to be a very significant link between time and depth. And what do we know about the Basic Open Water Diver -- she doesn't (or at least isn't supposed to) go very deep nor can she stay there very long.

If the BOWD stays anywhere near the limits of her training, she'll max out at 60 feet or so and even on air she will have a long time to look around -- PER THE NDLs. But, if she is in the tropics, she'll probably be breathing off an 80 (that's what, 12 L in the rest of the world?) with a SAC of 0.6 (and if male, 0.8). Now IF she has followed her training, she has done the basic calculation (here I'm using the PADI RDP) and found she can stay down for 55 minutes so that is her plan -- afterall, the shop is giving me a tank and shouldn't I be allowed to dive for the whole time? Ooops, at a SAC of 0.6 (which is being very generous for a new diver) she runs out of air at 42 minutes while her boyfriend runs out at 32 minutes.

So tell me, which is more important to plan, your NDL or your Air supply?

----------------------
John, SURE!!! But are we going to have an agency if Lesser has his way?

<ran out of thanks clicks>

 

[Thalassamania]

Let's look at this from a different direction for a moment.

41% of the DAN identified fatalities involved running out of air.

There are two ways to deal with that:

1. learn how to never run out of air, no mater what, because you know, full well, that if you do so ... y're gonna die! or

2. learn how to deal effectively with running out of air so that it is no big deal, just like many of us did for many decades.

I have always taken the later approach. I have always taught divers what to do when they are in an OOA situation. I have always stressed good watermanship and free diving skills along with the usual stuff.

Should we not give some thought to solving this on a skills basis rather than just on an avoidance basis?

 

[gcbryan]

I think the issue is that if running out of gas is a very common thing...it shouldn't be.

 

[Thalassamania]

OOA is an easy thing to avoid and an easy thing to deal with. Most instructors, however, do not seem to be doing either, when they should be doing both.

 

[gcbryan]

OOA is an easy thing to avoid and an easy thing to deal with. Most instructors, however, do not seem to be doing either, when they should be doing both.

Agreed. My take on the point the OP was trying to make however was that the latter is being addressed at least somewhat but for whatever reason too many people are running out of air when it should be a very infrequent thing.

Some instructors seem a little too cavalier in their approach to this subject. It should be very infrequent that an instructor would have to deploy his/her octo but its done all the time with very little lecturing regarding having to deploy it.

 

[lamont]

I agree completely.

I disagree completely.

The thing that is missing are the stats on how often divers survive being OOA. If there are a small number of OOA situations and they usually lead to fatalities (unlikely IMHO), then it would suggest a need to train to avoid OOA situations entirely. If there are a large number of OOA situations and very few lead to fatalities (very likely IMHO), then it would lead to the conclusion that being OOA isn't as dangerous as not knowing how to react safely to it and would suggest that training how to deal with OOA is the way to go to limit the relatively few fatal situations.

If a majority, or a large chunk of fatalities have OOA as the triggering factor, then it makes sense to train better to prevent that or mitigate the risk irregardless of how often OOAs are successfully dealt with.

 

[lamont]

There are two ways to deal with that:

1. learn how to never run out of air, no mater what, because you know, full well, that if you do so ... y're gonna die! or

2. learn how to deal effectively with running out of air so that it is no big deal, just like many of us did for many decades.

Door #3: Learn both. Gas Management and S-drills.

 

[Thalassamania]

Lamont, I agree.

The point of the discussion, however, is that Ken feels that if you learn how to not run out of air dealing with it will never be a problem, while I am saying that no mater what you do going OOA has a certain level of inevitability and that if you know how to deal with it, then running out of air will not be a problem.

 

[gcbryan]

and I think Ken's real point was not that OOA will never happen. His point was that under the current system running OOA is tacitly condoned in many ways.