Logging dives

[KevinColl]

Hi, probably a fairly basic question but after diving today am unsure how to log my dive. The dive location led us to surfacing in a cave after 22 mins. Completed all safety stop etc before surfacing. We then descended to continue on the dive for another 27 minutes until the end of the dive. My computer recorded as two separate dives, but given we were on a single tank should I just add the dive time together and count as one dive?

Would appreciate any thoughts.

Thanks

 

[Lake Hickory Scuba]

Hi, probably a fairly basic question but after diving today am unsure how to log my dive. The dive location led us to surfacing in a cave after 22 mins. Completed all safety stop etc before surfacing. We then descended to continue on the dive for another 27 minutes until the end of the dive. My computer recorded as two separate dives, but given we were on a single tank should I just add the dive time together and count as one dive?

Would appreciate any thoughts.

Thanks

We recently just uploaded a video on YouTube discussing logging dives. So far it has been a great talking point. In regards to your situation, it will be ultimately your decision on whether you want to log it as 1 or 2 dives. Here are a few things to consider. First do you considered the amount of time you were out of the water between the actual submerged times, is a sufficient amount of time to bleed off any nitrogen that was saturated during the first 22 minutes (SURFACE INTERVAL TIME, the time we bleed off nitrogen). If so, then log each dive separately. Second, try not to over think the science and math behind Henry's law. If your computer says you did 2 dives, then go with it, and log 2 dives. Most gear manufactures will program a small time frame into the algorithm of the computer, primarily for training purposes, such as a student doing multiple ascents with an instructor during training. This way as long as they do not exceed that short time frame, as they descend back down to continue their training dive, the computer will read it as only one dive. Hopefully others will chime in on this topic, but I fill highly confident that it will be a 50/50 split in responses. If you fill like you made 2 dives then log 2 dives. If you fill like you made 1 long dive, then log 1 dive.

 

[SeaHorse81]

Personally, I'd make it a single dive. There was no surface interval as such, just momentary surfacing, which happens sometimes.

 

[scubadada]

I would log it as one dive, others probably think differently. My computer will not count as two dives unless SI more than 10 minutes. What was your surface interval? You surfaced in a cave? Are you cave certified at less than 25 dives?

 

[northernone]

I generally count a dive as once cycle dry/wet/dry. I know guys who log dives as a cycle of atmospheric air/ SCUBA / atmospheric air. Both I'm ok with.

With a free diving background counting a dive being finished upon surfacing makes logical sense but I have frequent ascents and a historic great dislike of logging dives anyway so I opt for the method that results in less paperwork.

Now I just let my computer log what it wants and don't think about it.

I'm guessing you may have enjoyed a cenote cavern dive?

Regards,
Cameron

 

[Chilly_Diver]

It’s whatever you feel comfortable with. Logs are primarily for your own use. Personally, I would log it as one dive if I never left the water.

 

[TMHeimer]

If you're following your computer (or even tables if appropriate) correctly then it really doesn't matter. Personally I agree that it depends on how much of a surface interval. I do a lot of shallow diving and occasionally surface to check exactly where I am. My usual day involves maybe a 25 min. dive followed by a 40 min. one or vice versa. And a 25 min. SI--enough time to take tank, etc. off, warm up, whatever. For me that's two dives, and usually on one AL80 tank. I have logged two with as little as 10 mins. SI. Really doesn't matter. But I'd never consider it a second dive if I just surfaced for a few minutes and didn't exit the water.

 

[stuartv]

Hi, probably a fairly basic question but after diving today am unsure how to log my dive. The dive location led us to surfacing in a cave after 22 mins. Completed all safety stop etc before surfacing. We then descended to continue on the dive for another 27 minutes until the end of the dive. My computer recorded as two separate dives, but given we were on a single tank should I just add the dive time together and count as one dive?

Would appreciate any thoughts.

Thanks

Number of tanks used is irrelevant. I have used 1 tank for 4 separate dives, and I have used 2 tanks for 1 dive.

I don't agree with everything @Lake Hickory Scuba said in his post, but I definitely agree with the last 2 sentences.

 

[Paul M]

Me, I would log it as 1 dive. A nice feature of Subsurface ( & perhaps others as well ) is that multiple dive records like these can be merged together quickly as 1 dive.
As everyone says, it's your choice and it doesn't matter much either way. Your time under water will total the same.

 

[Neilwood]

One question I would have is whether the surface in the cave was at "sea level" ie were you still at depth in the cave or were you at "surface" depth?

If the depth of the descent and ascent are the same (you were effectively at the surface), then probably log it as two dives. If you were in an air pocket at depth (which would still be pressurised), you are effectively still at depth the entire time so no effective SI for offgassing.