Air hog etiquette.

[CUMBIAMAN]

A few days ago I was asked by a fellow diver some questions regarding air consumption and etiquette, your opinion will help to have a consensus.


Case 1

After planning for group dive (charter type) 1 hrs long, being an air hog you find out after 30 min that it would be wise to start surfacing (700 psi). Your choices are to signal the divemaster and abort everyone’s dive early or switching to the divemaster octo and share +10 more minutes of air (which you are not 100% sure you like). A third one might be surfacing alone or with your buddy.


Case 2

After some dives, considering your SAC, nitrogen, etc you find out your max dive time is 45 minutes. The dive group is planning a 55 minutes dive. What to do? Abort the dive at your 45 min? prolong to 55 min and make a deco stop? (the divemaster is aware of your time limit)

 

[dlofting]

I use more air than others. I just shoot my SMB and my wife and I ascend, do our safety stop and surface together.

 

[Aviyes]

Request a bigger tank and prevent the issue from happening.

 

[broncobowsher]

I dove with a couple that the husband was a hog. Started as a threesome. halfway through he would get our attention, wave and head to the boat. It was known and planned that way. No surprises. I think he eventually got a bigger tank to stay a little longer. But the key it the known and agreed to prior to diving that he is leaving. I stayed with his wife.

 

[caydiver]

If you are with a group it shouldn’t matter. Usually the last ten minutes or so are close to the mooring line. You sumply signal to tje others that you are going up and off you go. You can give everyone the heads up before you get in the water. If you are in a buddy team with one person you both need to go up. The DM is not there to share air for the purpose of prolonging your bottom time so rule that out. There are several techniques to improving your air consumption. Have you considered hiring a personal DM for a dive and using it specifically to get better control if your breathing? For some something ad simple as humming can help.

 

[Diver0001]

A few days ago I was asked by a fellow diver some questions regarding air consumption and etiquette, your opinion will help to have a consensus.


Case 1

After planning for group dive (charter type) 1 hrs long, being an air hog you find out after 30 min that it would be wise to start surfacing (700 psi). Your choices are to signal the divemaster and abort everyone’s dive early or switching to the divemaster octo and share +10 more minutes of air (which you are not 100% sure you like). A third one might be surfacing alone or with your buddy.


Case 2

After some dives, considering your SAC, nitrogen, etc you find out your max dive time is 45 minutes. The dive group is planning a 55 minutes dive. What to do? Abort the dive at your 45 min? prolong to 55 min and make a deco stop? (the divemaster is aware of your time limit)

In case 1 I agree with Aviyes. If you use more air than average and you're aware then you can always request a bigger tank. Alternatively, you don't necessarily need to make the dive at the same depth as the other divers. I once dove in Turkey with a guy who used a lot of air. We arranged for a 15l tank for him (the other divers were using 10l tanks) and the dive sites we dove mostly lent themselves to swimming a line 5 meters shallower than the other divers. Doing that he was never the first one on the surface.

Secondly, I would think the DM would want to know if you think you'll be out of air earlier than the rest. Sometimes it's ok to surface with your buddy once your air is up and let the rest of the group carry on. In that case, give the DM a chance to adjust the dive plan in order to accommodate.

In case 2 it sounds like you're using tables when the other divers are using computers. In that case you need to follow your table. Again, it is important to tell the DM about that before the dive so he/she can adjust the plan if necessary. Personally I think that everyone diving in groups with a guide should have their own computer these days. Rent one or buy one (they're getting very affordable).

R..

 

[Lorenzoid]

In either case, buddies should have some idea of each other's consumption rate and thus some idea of how long their dive will be. My two cents: Assuming the buddies use tanks of the same capacity--which does not necessarily have to be--the "group" dive is over when the buddy with the higher rate reaches some agreed-upon turn pressure, and at that time the buddy team should turn around and/or ascend, either to the surface or at least a shallower depth. Unless the dive profile needs to be square for some reason, the buddy team can ascend to a shallower depth before the rest of the group. But the dive is over for the buddy team when the dive is over for the buddy team--simple as that. I don't like the idea of relying on the DM. The DM should be aware of the buddy team's anticipated dive time, and the DM should be aware that the team may need to turn around and/or ascend to a shallower depth (or the surface) sooner than the rest of the group.

 

[Nick Steele]

+1 for requesting a bigger tank.

For my first 6 dives after open water I had a chance to use a cave filled 84, 4 hp120’s, and a hp100. So far with the lp84 and 120’s I wasn’t the first one done with air. With the hp100 I was first to use my air.

I will always try to get hp120’s if possible and even if I come up with 1500psi left I won’t mind. I am mindful of my SAC after dives and I hope to get it under control one day.

 

[Seaweed Doc]

Another in favor of "larger tank."

I've been in a non-supervisory role (as far as SCUBA goes) with marine biology students where I wasn't sure about their air consumption relative to mine. I wanted to keep an eye on them for the whole dive, so I trailed behind them as a divemaster led us on a tour, hanging out with a second divemaster. I also made a point of being about 5' shallower than the rest of the group for most of the dive. That little bit shallower was all it ever took to hit time limits (usually set by DMs) rather than air limits for me.

I am NOT a fan of sharing air with a divemaster. The divemaster has a responsibility to all divers in the group. If a diver loses buoyancy control while on a safety stop, [SARCASM] which of course never really happens and certainly never under a moving dive boat [/SARCASM], the divemaster needs to be able to intervene physically and immediately, not dragging or even taking time to signal his or her parasite. Or pick your alternate crisis. The divemaster doesn't get a +1 to the party.

 

[Rred]

I sometimes get tunnel vision when I'm diving. That is, I don't have eyes in the back of my head. So one day I was surprised by the feeling of my custom-bite-wing regulator being ripped out of my mouth, puzzled with a "that's not hardly right" feeling, only to find an OOA buddy hanging and panting off it.

Another time I felt a drag at my side, since I had a nice fat 90+cf steel tank and my buddy just had an 80, he just figured he'd borrow some air from my octopus. Hmm...

It is nice to have spare air, but I think that if I had burned my tank out, I'd remember that the spares are FOR EMERGENCY USE and you really want to leave that extra air alone, not burn it as a convenience. I'd signal the divemaster (if possible) and ascend. I'd signal "you" "sit/stay" "me" "up" "ok" and make my way up. I would not expect everyone to terminate their dive. Obviously, your divemaster and group may have their own thoughts on that.

But to me it is not so different from the usual "I'm going up to take a look around and see where we are, you stay down here."

That's also part of why I like J-valves. As the USN and NOAA both point out, the J will reach out and remind you that you're almost out of air--even if you've been distracted and haven't been watching your gauge.