Diving after a bounce dive

[wKkaY]

So this happened on my most recent dive. There were 3 groups of us diving a 27m deep wreck, on EAN32, first dive of the day.

My two buddies and I jumped in and visibility was around 1m - worse than anything I've done before After descending down the anchor line, we proceeded to swim along the wreck, but after a few kicks buddy #2 went missing. Buddy #1 and I looked around for a while, then aborted and went up. On the surface, we met buddy #2 and another group who aborted. Total dive time was 12 minutes.

The diver from the other group was regretful that he couldn't finish the dive, as was I. At that point I was thinking of going back down with just him. But I didn't ask, as I was unsure about diving shortly after bouncing and wanted to be prudent. So we all sat together on the boat waiting for the last group to finish their dive

What are your thoughts about this situation, from a decompression theory/practice perspective?

 

[Stoo]

To start with, I wouldn't really consider that a bounce... more a really short dive. I would have gone back down, but added several minutes of stop over anything my 'pooter might have told me.

I'm assuming you had lots of air left and all that stuff.

I should add that had this been the third dive of the day, I probably wouldn't have.

 

[RainPilot]

If you were only on the surface briefly, most DC would treat it as a single dive. With a really short dive time like that I would personally be fine with going down again.

The major issue is normally when you have bubbles from a previous dive and then recompress these on a short bounce (fetching an anchor etc) which can allow bubbles to pass through to the arterial side with varying levels of mayhem ensuing.

The amount of ongassing from a short dive like that would I think be low enough that it should be fine.

Maybe @Dr Simon Mitchell or @Duke Dive Medicine could help out...

Edit. Seems Stoo and I were simul-typing. I agree with his points as well.

 

[RyanT]

I concur with Stoo and RainPilot

 

[scubadada]

I concur with Stoo and RainPilot

Exactly, as long as your surface time was relatively short, your computer would consider it a single dive and all the dive information would be taken into consideration.

 

[BoltSnap]

Was the diver from the other group you were thinking of diving with going to be an "insta buddy" and you would have just gone down without making a real dive plan together? I wouldn't have done that if that were the case. I don't like last minute rush type of diving where the two buddies aren't really buddies and no one discussed anything in detail and confirmed it before going diving. It usually ends up another cluster-f dive. If my dive went bad for any reason and I had to surface from any depth deeper than 15 meters , I usually don't go immediately back in to deeper depth. I need to sit on the surface and think about what went wrong and discuss it with my buddies and learn something from it before I continue diving. I certainly wouldn't go in right away with an "insta buddy" from the surface before having the chance to make a real dive plan especially when the depth is going to be deeper than 15 meters on this dive.

 

[wKkaY]

Thanks everyone for your input, and the additional perspectives to think from (gas, repetitive dives, instabuddy)!

 

[boulderjohn]

whether your computer thinks of it as one dive or two depends upon the computer. Mine would probably treat it as two. I get a lot of one or two minute dives on my computer because I dropped down and did something like set a safety bottle at 20 feet before coming back up, joining the group on the surface, and then descending on the real dive. It really doesn't make any difference on the second dive--you just have to decide if you want to bother with making a correction when you download the dive profiles.

On the PADI table version of the class, there are questions in which students have to calculate the minimum surface interval required between dives. On one case, the correct answer for the imperial version is 4 minutes, and the correct answer for the metric version is 0 minutes.

 

[Bob DBF]

whether your computer thinks of it as one dive or two depends upon the computer. Mine would probably treat it as two.

My dive computer will count any dive within 10 minutes of surfacing as the same dive. Another good reason to read your computer manual.


Bob

 

[Patoux01]

Much like others have said...
I won't do a bounce dive after a bigger dive (ie one in which there could be a substantial level of bubbles in the blood).
What you did however, does not typically allow the bubbles to be really there (not enough gas load).

That's my view on it...