How to calculate number of dives

[NeurosurgeryNP]

I am a novice diver. I was wondering how you calculate the number of dives you ave gone on - i.e. - a 4 hour boat trip with two dives, 2 tanks - does that count as two dives or a single dive in your log book? I know it is a silly question, but after getting certified over 8 years ago, I am just now getting back into diving after refreshing.

[crosseyed95]

Originally Posted by NeurosurgeryNP

I am a novice diver. I was wondering how you calculate the number of dives you ave gone on - i.e. - a 4 hour boat trip with two dives, 2 tanks - does that count as two dives or a single dive in your log book? I know it is a silly question, but after getting certified over 8 years ago, I am just now getting back into diving after refreshing.

Welcome back to diving!! To answer your question, if you did two dives off the boat then you would record this as two dives in your log book. Doesn't matter that you only took one trip with the boat or that it was a 4 hour boat trip. You still put your equipment on twice, splashed off the boat twice, safely came up twice, etc.

[IrishSquid]

If you're using a computer, most will log the dives as 1, 2, 3, . . . . . .
I use an Aeris and unless I'm at the surface for more than a few minutes, it is one dive.

[NeurosurgeryNP]

Thanks for your replies. I know that the question is silly! I just wanted to know how to log each dive in my logbook.

[NoTime58]

Originally Posted by NeurosurgeryNP

Thanks for your replies. I know that the question is silly! I just wanted to know how to log each dive in my logbook.

Logging each dive after I get back on the boat helps me to remember the dive better. If I forget something I can always ask my dive buddy for a little memory refresher.

[Zenagirl]

Your question isn't silly at all. To answer you another way, you've done 1 charter and 2 dives....so you log it as 2 dives.

[h2odragon1]

Log each dive as you finnish. Date, depth, time from submerging to surfacing, how much air you used ( pounds,or bar), some of the things you saw, who your dive partner was. You may want to add fresh/sea water, type of suit you wore, (mm,full/shorty,two piece),how much weight, pressure group surface interval.

[ChrisA]

Originally Posted by NeurosurgeryNP

I am a novice diver. I was wondering how you calculate the number of dives you ave gone on - i.e. - a 4 hour boat trip with two dives, 2 tanks - does that count as two dives or a single dive in your log book? I know it is a silly question, but after getting certified over 8 years ago, I am just now getting back into diving after refreshing.

Just remember the purpose of logging dives. Why divers started doing it. They had to keep track of their depth and time and length of the surface interval so they could use dive tables. Now that we have computers we forget this.

I use the Navy dive table definition. It is a dive if you were down long enough to have any residual nitrogen and the surface interval was over 10 minutes. Yes I know: Way to technical. The 10 minute rule allows you to come up an look without the need to count as two dives

Some training agencies that count logged dives say that a dive has to be at least 20 minutes. So if you need 60 dives for a DM card they can't be a series of 5 minute "dives" where you do 20 a day. (I actually heard of someone who tried to do that.)

[ScubaJW]

I log every dive so I can remember each issue, what I saw, and etc... - because every dive, there will be something new and you never know!

[MSilvia]

Originally Posted by NeurosurgeryNP

I was wondering how you calculate the number of dives you ave gone on.

I use a simple formula: The number of times I've submerged at the start of a dive, plus the number of times I've returned to the surface after a dive, divided by two.