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NeurosurgeryNP
03-09-2008, 11:36
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
03-09-2008, 11:47
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
03-09-2008, 12:20
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
03-09-2008, 12:50
Thanks for your replies. I know that the question is silly! :smiley29: I just wanted to know how to log each dive in my logbook.

NoTime58
03-09-2008, 15:56
Thanks for your replies. I know that the question is silly! :smiley29: 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
03-09-2008, 16:16
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
03-09-2008, 22:33
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. :smiley20::smiley20:

ChrisA
03-09-2008, 23:02
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
03-11-2008, 12:34
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
03-11-2008, 12:51
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. ;)

Rockhound76
03-11-2008, 14:29
About logging dives (in general):
My 15yr. old didn't want to record a river clean-up dive he want on because it was "too short" and "not deep enough". We both aborted after 20 minutes or so, after we were swept downstream.

I asked him "why" did he log dives? He sort of shrugged and i pointed out that we discussed some of what went wrong that day and what we would do differently (i.e., more weight and lines to help us work the bottom.)

"Wouldn't it be worth logging that dive and noting what you would do differently next time? Wouldn't it be worth pulling out that old log many years from now and using it to remember that we had a good time?" I

I showed him my ragged old logbooks, lamenting the fact that about 10yrs. of some very good diving was missing because i got too lazy to log it.

So, he pulled out his book and logged the dive.

About your specific case: Log any dive of merit. I always log any series of dives as seperate events unless my SI is under 10 minutes. Even then, I have a couple of dives I logged in that circumstance (jumping in to retrieve an anchor, I noted what happened.) For Table planning, it was still one dive, but showed up as two in the book. It's only paper, you know...

mark44883
03-11-2008, 22:34
dives a dive good or bad just hope you have more good then bad

solodiver
03-11-2008, 22:36
Going on 34 year now certified,.... what's a log book?

ScubaJW
03-11-2008, 22:37
Going on 34 year now certified,.... what's a log book?

Uh, is that a joke? ;)

Kabniel
03-12-2008, 15:52
Thanks for your replies. I know that the question is silly! :smiley29: I just wanted to know how to log each dive in my logbook.


To use a popular quote..."the only stupid question is the one you don't ask"

:smiley20:

cummings66
03-12-2008, 21:07
I don't count the number of tanks as anything regarding the number of dives. I often will get 5 dives per tank, I dive an HP120 and my buddy is an airhog. I'll log how many times I go down for the purpose of diving.

Sort of like flying, you can log the flight if you intended to do it and had to abort it even, ie engine failure at takeoff can be counted as a flight for logging purposes. Now if I taxi to the fuel pumps I can't log that unless I meant to fly. I treat diving the same way, I must have been in the process of diving. I've logged 1 minute dives where I either learned or found something special, and I've not logged short dives because it didn't meet any of my requirements, although the computer did log it.

In the end, it's your logbook of memories, log what you wish to remember.

cmburch
03-12-2008, 21:54
I don't know. If I dive then surface, then dive again without getting out of the water, my computer logs it as 2 dives. I would only count it as 1 dive unless I got out of the water or changed my tank. This question seems strange to me. I have never really given it much thought. I guess I would only count a dive if I got out of the water or changed my tank in the water. I would never changed my tank in the water though.

finflippers
03-12-2008, 22:21
If I am up 10 minutes or longer I count it as another dive. Less then 10 Minutes I count it as the same dive.

emcbride81
03-12-2008, 23:29
I don't know. If I dive then surface, then dive again without getting out of the water, my computer logs it as 2 dives.


Strange..most computers have a surface interval time requirement to distinguish between dives. If I had that happen to me I would have 4 times the dives I do :smiley36:

I am with Finflipper, 10 minutes between means a new dive...in fact I think that is the interval my computer uses. I also agree that more than one dive can be done on a tank. Some of my lakes and quarries are too boring to spend using an entire tank on one dive!

cmburch
03-13-2008, 04:49
Strange..most computers have a surface interval time requirement to distinguish between dives.

Yes, mine resets at 3 feet or less after 10 min. I am responding to what I would consider is one dive (the way I would count it). The only time I would not use up my tank would be an aborted dive due to bad conditions or some other problem. Upon further contemplation once when diving for less than 10 min my fin strap broke. I went back to the beach to replace the strap then back in to finish the dive - I would only count it as one dive since I am completing my dive. So I would define one dive:
1. Getting out of the water and resting before next dive.
2. While on the surface moving to a new location.
3. Or if there were someway to change my tank in the water then start a new dive.
I would not log in my logbook (other than possibly the profile and perhaps the reason as a side note) having to surface then remain on the surface for over 10 min for some reason before completing my hunting/diving. I consider each dive a hunting session, I guess. I only SCUBA dive in the ocean.

cummings66
03-13-2008, 07:23
I find that because I dive with new divers a lot that they use up their tanks way before I do mine. So for me I have got as many as 4 dives on one tank to theirs, but solo by myself I have got as many as 5 dives. Those aren't short dives, usually 30 minutes or so, sometimes down to 60 or 70 feet. I can use up a tank, but depending on location it can take forever and frankly, in a quarry there's just not that much to see.

Maybe if I had an ocean nearby I would do as you do and be able to do one dive per tank, but now that I'm diving double HP120's there is absolutely no way on Earth I can do one dive on those without exceeding NDL on paper, tables, and any other way you count it.

When I finish my deco course it may change, but for now I can't do only one dive per tank.

Of course, as I said, the log is for memories, sometimes proof for courses, so log what you wish to log because it's your memories. Never be creative, or lie. Make it an honest accurate account and all will be well.

divergirl
03-14-2008, 13:30
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. ;)


I use this one too :P

mobeeno
04-12-2008, 20:03
I think you can do it anyway you want as long as you are consistent and it is the system you understand