Curious question: Intentional deco dives in Coz?

[pipedope]

There are a couple of dives here that it is common for people to go into "deco" on their computer, but it's often not TRUE deco. For example. Maracaibo is best between 150 and 170. The top of the wall begins at 90 feet. This dive is too deep for nitrox, so invariably, people typically have deco obligations. However, those deco obligations typically go away as you rise to a shallower depth and stay there for awhile. This could be considered a deco stop, but it's in our dive plan as a multi-level dive. The computer typically clears before you reach the stop on your computer or stay for the time your computer initially tells you. We also do an extended safety stop on dive like this. I don't feel like I am explaining this very well...so I hope it makes sense

Punta Sur is another one that soemetimes puts people into deco for a short period of time.

While this practice is fairly common it is a good idea to plan these dives as deco dives with all the planning and equipment considerations that come with them.

The reason is that for a significant part of the dive you do not have the option of going directly to the surface so any problems must be solved in the water at depth.

I am in favor of divers doing dives the way they want as long as they understand what they are doing.

 

[miketsp]

There are a couple of dives here that it is common for people to go into "deco" on their computer, but it's often not TRUE deco. For example. Maracaibo is best between 150 and 170. The top of the wall begins at 90 feet. This dive is too deep for nitrox, so invariably, people typically have deco obligations. However, those deco obligations typically go away as you rise to a shallower depth and stay there for awhile.
..snip..

I find this a strange definition - "it's not TRUE deco".
If the dive has to end at that moment due to an OOA or other failure you have a deco obligation, you have a ceiling and it is a deco dive.
The fact that you will pay your deco off by doing a shallower part of the dive instead of hanging mid-water or on a shot line is not relevant. The tourists should be warned.
I have been on a few dives in tourist locations where there was a deco obligation during part of the dive and some divers without computers were not aware of the ceiling. This is wrong.

 

[Scuba_Steve]

Well put Mike. I was thinking the same thing.

All in all, this type of diving shouldn't even be talked about in a Rec forum, as it basically gives one the green light to do 150ft+- dives becuse it's warm and you can see a long way, on an ALU80 for pete's sake! (OK maybe you have a 100...so what?)

Maybe we wouldn't call this one an "undeserved hit" then ?

I do however realize that there is bascially no dive plan at all, for most doing these dives (other than ride the 'puter). Heaven help the unlucky, they're gonna need it.

 

[Charlie99]

The common phrase of "all dives are deco dives" is particularly appropriate for this discussion.

My rather liberal Oceanic computer will still shows NDL time remaining while divers doing the identical profile with Suunto computers show several minutes of deco obligation. Is one of us doing a deco dive and the other not? That clearly doesn't make sense.

The line between a required deco obligation and "immediate ascent to the surface is OK" is a very fuzzy one. The risk gradually increases with depth and bottom time. A few minutes of deco showing on a computer doesn't constitute a true overhead. You can still do direct ascent with high likelyhood of no problems. Not at all a good idea to do, but also something that I wouldn't hesitate to do to effect the rescue of a diver. OK, off of the

In addition to Punta Sur, the other place I've been into deco in Cozumel is at C-53, when doing it as a 2nd dive with about 1 hour SI after an earlier wall dive. Before the dive started, the DM knew that we would be pushing it a bit when he and I went hunting for seahorses for 10 or 15 minutes after the other DM and other divers finished the wreck dive and went up. The Captain also knew that we were going to be doing a long ascent.