Protocol when diving in group

[TMHeimer]

A couple of times when I was diving air and the rest had nitrox I got the signal to ascend to the safety stop solo. Once my buddy was too cold for the second dive and the DM said to go ahead and dive it alone. I have also seen others being signaled to safety stop solo. These were all U.S. charters. I would imagine it is true that this varies with each dive op.

 

[spc751]

I like diving with Underwater Technical World in Riveria Maya because they group divers with DMs by experience. The DM keep track of everyone's air pressure and when one diver gets low the DM pairs that diver with the diver with the next lowest air pressure, deploys the SMB, sends them to the surface and the boat picks them up.

Two years ago I was the first diver to the surface. Now I am usually the last!

 

[TSandM]

If you really think about the issues involved, I think your question really answers itself.

New divers use gas faster. The solutions are several: Keep the new diver shallower than the rest of the group; give the new diver a bigger tank; send the new diver up when he's low on gas; and share gas with the new diver when he is low to continue the dive.

Consider those approaches: If you keep the new diver shallower, he uses gas less quickly, but he has to have someone with him, because of all the divers in the group, he's the most likely to have an issue which might require assistance. So this strategy, in a place like Cozumel, works only if the new diver hires his own DM, or is paired with another novice.

You can give him a bigger tank. I know Aldora uses steel 120s for their heavy breathers, which really does give a longer bottom time. But if everyone is diving them, we still have the problem.

Sending the new diver up alone when he's low on gas seems to me to be the absolute WORST answer. He is low on gas; that's why you are sending him up. His consumption rate is high, which is why he's low. Is there any guarantee he's going to be able to ascend and do a safety stop on the gas he has? Is there any guarantee he's going to be able to stay on the upline and get to the boat? Ascents are one of the times that things are rapidly changing in a dive, and things like alternobaric vertigo occur, and reverse blocks. I really hate to see ANYONE ever sent up alone, but new divers are the worst.

Sharing gas with a diver who is low seems like a pretty reasonable strategy, but not if you look at it closely. To begin with, as someone has already observed, this removes the DM as an emergency gas source for anyone else with a problem -- which wouldn't matter, if everybody were diving in defined buddy teams, and maintaining adequate gas reserves, but that's all too often not the case. Further, if you are sharing gas with the DM and, for example, have a buoyancy oops and lose that donated reg, are you going to be composed and calm in retrieving your own? And do you have enough gas to do your ascent by yourself when you're rattled? Do you know how to tell?

In my opinion, the new diver should be given the largest tank available, and his buddy should commit to ascending with him and making sure he gets back on the boat safely, even if that means the buddy has to accept a shorter dive. Since, in resort locations, everyone has paid significant money for the trip, and nobody wants a short dive, that really means that a novice should either be paired with another novice who is likely to use gas at the same rate, or should hire his own DM.

 

[Steve_C]

Diving in Cancun. Slow drift at 35 ft over a reef. Excellent viz of at least 60 ft. DM + two experienced divers + and one "swimmer". Swimmer was using air fast. DM took the swimmer, went up about 20 ft, passed his REG to the swimmer, and suspended swimmer below him. We all drifted as a group. Seemed to work very well in those particular circumstances. DM could easily observe the two of us below him, swimmer relaxed and was using much less air. With about 5 minutes to go DM switched swimmer back to his own air and let him go so we could all ascend separately. In an emergency DM could have swapped swimmer back to his own air and gone and offered assistance with the group all making an ascent together from that point. For that kind of easy dive, DM probably had a fair chunk of an 80 left at the end of the dive.

 

[nolatom]

I recall in West Palm/Riviera Beach that the drift dives were pretty much 'group' dives and not particularly buddy dives. When I got to 900 or so and wanted to ascend, I let the DM know (he was dragging a flag for the boat to see). Then I headed up and the boat was there, I could see it anyway from depth which was about 50-60' along the tops of the reefs.

Others did the same. It seemed safe enough to me at the time. Now I guess after reading some bad accounts over the years about ascending alone, I'd probably look for someone else who was signalling ascent and go with them, or pick a buddy at the outset where we agreed we'd surface together.

 

[Steve_C]

I recall in West Palm/Riviera Beach that the drift dives were pretty much 'group' dives and not particularly buddy dives.

At nearby Jupiter we were buddied and went in as a group. My instabuddy had a camera the size of a small mini-sub. We splashed together but by the time he was oriented and ready it was the just two of us. Reduced viz (30ft) probably contributed so we did a buddy drift dive (I carry an SMB with me). Probably better since we both liked to stop and photograph anyway.

 

[TSandM]

I just shake my head. If you don't have a buddy, what is your guarantee that ANYBODY will be close enough to help you if there is a problem? What information do you have to suggest that anybody in the group will have enough gas to get you and them up to the surface, if you have a freeflow or a blown hose, or --shudder -- fail to monitor your own gas until you're low or out?

Diving in a gaggle and depending on the DM is the way people learn to get themselves into the kind of situations we read about in the Near Misses section, all too often. Separated . . . low on gas . . . poorly controlled emergency ascents. It all comes easier when you have no plan, no buddy, and a misplaced confidence that somebody else is going to save you.

Sorry . . . I'm tired and grumpy tonight, but I really feel strongly about this.

 

[BabyDuck]

my protocol? i don't dive in a group. even if there is a wad of people on the same dive, i have a buddy. my strong preference is that *everyone* has a buddy and that we all know if we're going up as a wad or going up in buddy pairs/triplets, but on a dive such as outlined in the original post, with dm's riding herd, that might not be possible. but *i* will have someone i'm responsible to who is also responsible to me. not negotiable. diving in a wad is an invitation to disaster.

 

[USFpsychDiver]

Same thing happened to me in my first post-certification dives in the Bahamas. I had no confidence in my dive skills and was sucking down air like crazy. On each of my first two dives the DM shared air with me when I got low well before the rest of the group so that the whole group didn't have to surface after a 30 minute dive. As the week went by I got more relaxed and my air consumption got better and we were able to ascend with the 'early' part of the group (was a mixed bag of divers, some off in buddy pairs, plus a couple of groups with DMs, one coming up earlier than the other). Experience, relaxation, good buoyancy and trim, going slow, will all improve air consumption. Soon you'll be one of those folks who floats up and down effortlessly and manouvers at will with tiny fin flutters, and consumption will be much better. There are arguments about the overall benefit of bigger tanks; true, they hold more air, but they also have more drag, and some argue that the extra effort of managing the larger tanks increases air consumption offsetting the greater capacity. I'm going to try an experiment on my next dive and do back-to-back dives in LP85s and LP95s (doubled) and see how much using the bigger tanks actually buys me.

 

[MeraSonnet]

If you keep the new diver shallower, he uses gas less quickly, but he has to have someone with him, because of all the divers in the group, he's the most likely to have an issue which might require assistance. So this strategy, in a place like Cozumel, works only if the new diver hires his own DM, or is paired with another novice.

As a fairly new diver myself with 30 drift dives in Cozumel (the OP's next destination), I second this advice to consider a private DM if the OP is diving in Coz without an established dive buddy. Being new to drift diving in Cozumel, and ascending to controlled safety stops and surfacing without ropes, there are HUGE benefits to such a strategy. All 30 of my Cozumel dives have been off of the smaller fast boats with 6 divers, rather than the big cattle boats which I find chaotic. Without exception in those 30 fast boat drift dives, we all dove as a group trailing behind/beside the single DM. The DMs never ensured the divers were buddied up -- leaving that up to the divers themselves. Though I always had my buddy, there were frequently solo divers present in the group. I would not myself want to do that solo-but-in-a-group strategy in Cozumel, because though the solo folks were close to us, they were also kinda doing their own thing and we buddies were focused on our own thing... not really close enough for an emergency. And no guarantee for the solos that someone was watching their back, which could be a concern in Cozumel's fast-moving currents. Consistently, the DMs would turn and periodically check everyone's air via hand signals, and we would begin ascent as soon as anyone in the group responded that they were at 700-1000 PSI remaining. For those not real experienced in drift diving at a location like Cozumel... again, there are no ropes. You must control your ascent and achieve the safety stop all on your own, while floating in the current in a cluster with your dive group. This ascent plan happened as described for all 30 dives across 3 different fast boat dive ops and many different diver groupings, with no exceptions. The Cozumel DMs never shared air, never sent a lone diver or buddy couple to the surface alone. On some of the trips, because we had a brand spanking newly certified companion join us, we used a private DM at both Scuba Mau and at Blue XTSea, with superb experiences at both. The private DM allowed us to keep our newbie's dive profile safe and at a good pace for him, without hijacking the experience for other advanced divers on the boat. The Private DM was an extra ~$50 a day (2-tank dives). It was worth it for us.