Sharing air to extend bottom time

[redacted]

I think I see where this could go. But does it warrant an air sharing C-card or is it just something like a PADI specialty? Should a mask removal C-card be a prerequisite?

 

[Tigerman]

...
Whilst I live/dive in a 'vacation' area, I really don't see much of 'vacation divers', except occasionally sharing a boat with them - my diving is pretty specific nowadays. That said, in 20 years diving on 5 continents, I've never heard of divers doing this...and have never considered doing it myself. It always seemed wrong to me - and I've been prone to some very dubious undertakings in my time....

I have seen it and I havent been diving for 20 years nor on 5 continents (only 3 continents and only short of 6 years).

I would have no problem with two random doing it, but I do have an issue with seeing DM/instructor/guides doing it with one of the divers they are leading dives for, simply because once they are sharing air with a "guest" they are now unable to give aid to any other "guest" they have taken with them on the dive.
If its the DM/guide/instructors job to ensure everyone is safe or not is one thing, but the fact is that Ive seen several times that they need to aid divers for whatever reason and already having someone on your octopus would seriously hamper this task.

 

[caseybird]

Since cards are nothing more than cheap pieces of plastic, I consider mentoring sufficient training for voluntary air sharing.
The course would go like this:
When you reach 1000 pounds, signal me. I will then give you my 7 foot hose to breath from. We will swim closely together. You can hold onto my BC strap if necessary. When I reach 1000 pounds, I will signal you to put your own reg in your mouth, purge and breath normally. We will then commence a normal ascent, being careful to monitor ascent rates and NDL times.
See, Mentoring works perfectly in this situation. No need for fancy ageny nonsense.

 

[faze]

As a lot of people far more experienced than I have commented on the air assist I will not comment on that element but on the plan.

When we take people on a dive we stick to the plan - that plan is that we turn at 100 bar and we reach the line when the first diver reaches 50 bar - regardless. It's down to us to judge the usage underwater - so when the first person signals 100 bar you check the dive time and do a quick calculation as to how long you need to get back to the line (considering current, profile, etc.)

If we get back to the line and some in the party have plenty of air left then we extend their dive AFTER those approaching 50 Bar have started their accent.

So my point is - if the dive plan in the original post was to start the ascent at 700 psi, I would have an issue with the DM apparently deviating from that.

 

[supergaijin]

How long do you think we'll have to wait until we see cave divers sharing air at the beginning of their dives?

 

[DevonDiver]

Since cards are nothing more than cheap pieces of plastic, I consider mentoring sufficient training for voluntary air sharing.
.... No need for fancy ageny nonsense.

I think the suggestion to submit this as a course (at least, my suggestion to do so) was as a means to test agency response to the practice, rather than advocating the need for formalized training in the skill.

 

[Peter Guy]

How long do you think we'll have to wait until we see cave divers sharing air at the beginning of their dives?

In my very limited experience, I've seen cave divers share air at the beginning of many of their dives. In fact it is standard practice to do a round of air shares prior to the start of the dive.

 

[supergaijin]

In my very limited experience, I've seen cave divers share air at the beginning of many of their dives. In fact it is standard practice to do a round of air shares prior to the start of the dive.

For the purpose of extending bottom time?... or as a drill?

 

[SeaCobra]

You're right, although I have been reading this entire thread, I still just don't understand. I find this practice, at best, very unnecessary. If your skills are so elite, then I would imagine your SAC rate is as well and there would be no need for this. If your skills and comfort in the water mean that you cannot get a decent dive on a nice reef within recreational limits on AL80, well then, "borrowing a cup of air" is indeed dipping into your safety reserve.

 

[redacted]

You're right, although I have been reading this entire thread, I still just don't understand. I find this practice, at best, very unnecessary. If your skills are so elite, then I would imagine your SAC rate is as well and there would be no need for this. If your skills and comfort in the water mean that you cannot get a decent dive on a nice reef within recreational limits on AL80, well then, "borrowing a cup of air" is indeed dipping into your safety reserve.

Would you care to define the "safety reserve" you have referred to?

While you are imagining things, see if you can imagine short fills or limited tank size availability.