# of dives vs. time under water

[Scuba]

The standard for diving experience is the number of dives a diver has accumulated, while the time spent underwater is a non-subject.

The importance of number of dives is that it demonstrates experience and hopefully some degree of competency in what are sometimes two of the most potentially dangerous aspects of diving: descent and ascent.

On the other hand time under water can be an indicator of, hopefully, diving experience and competency. A large amount of time under water denotes many descents and ascents. Also under water is where we learn to be competent divers and encounter a much wider diverse range of experiences.

Some proffesions where experience is very important measure it more by hours logged than times experienced, such as pilots.

What are some of yours thoughts on this.

Why does diving measure experience by number of dives?

Peter

 

[100days-a-year]

It would be hard to compare even times without taking into consideration the conditions,whether the dive was run by an Instr/DM or not,the depth and whether or not there was planned deco,multiple gasses etc....I'd say one cold water wreck dive to 250' on mix with a drysuit would be equal to 100+ dives in Coz

 

[neil]

A single scuba dive is a series of connected skills that must be performed in a particular order. It seems to me that the more you have performed this series of skills, the better you will be at diving. Which gives more experience in your opinion, 4 twenty minute dives, or one 80 minute dive? It's a really good question. I think it's some combination of time and number of dives, and my preference when judging experience would be number of dives and the conditions they were done in.

Neil

 

[Scuba]

Which gives more experience in your opinion, 4 twenty minute dives, or one 80 minute dive?

Let us use this ratio as an example.

If both divers have 100 hrs experience

20 min. diver will have: 300 dives

80 min. diver will have: 75 dives

Someone looking at the number of dives will consider the 20 min. diver much more experienced, even though they have the same amount of underwater experience.

In this case I think its safe to say that the 20 min. diver will have been exposed to a wider range of descent and ascent conditions. While the 80 min diver will have the greater exposure to underwater experiences.

Now lets look at it from a different perpective, the number of dives standard in used today.

Assume both divers have 100 dives:

20 min. diver will have: 33 hrs. underwater

80 min. diver will have: 133 hrs. underwater

Quite a different view now. Is it not?

Granted experiences will vary widely dependent on conditions encountered. But all things being equal, the sole emphasys on number of dives can be quite misleading.

I think both number and time are very important and should both be considered, along with type of dive perhaps.

Peter

 

[Liquid]

The 80 min diver will had made only shalow dives, while the 20 made all kinds of dives. Some go the extreme of logging not single dives, but DAYS of diving. As there are skilled used once every day (like planning, that is if you do exactly what you plan).

 

[TexasMike]

we must also take into consideration the environment where the diver has accumulated the X number of dives for Y time underwater.

I dive frequently in two local scuba parks. One has an average depth of 20 feet, the other 35 feet. Both have almost swimming pool like conditions with decent vis and hardly anything to reach out and grab or hurt you.

Theoretically, it's possible for someone to build up a log book of lots of dives and time in either one of these venues.

And while gaining tons of experience here is a good thing, it won't really prepare the diver for what they might encounter diving off a boat in moderate to rough seas, moderate to ripping current, on a wreck or challenging reef.

So if I encountered a diver who could show me that they have "X" successful dives in conditions I just described, I would be more likely to give them deferrence over a diver who had twice to three times as many dives in the scuba parks.

A personal example was my first trip to the wrecks off of the NC coast. Fortunately there was no current, but the rest of the dive profile definitely had me "outside my box" from previous experience. I had fun and was able to complete most of the dives, but the trip as a whole definitely got my attention.

Additionally, we must take into consideration how well the diver performs in the water. It's entirely possible for one diver to have bunches of dives in their log and still not have all the necessary items down as cold as needed, while another diver with just 25 dives would give the best of us a run for their money.


But enough of this rant.....let's agree to say that we are all still learning to do our best for the type of diving we aspire to, AND GO DIVING!

 

[art.chick]

Would seem to me that for commercial diving, you may be lowered & raised by means other than your own power & thus the "ups & downs" have little to do with your overall experience.

In recreational diving, having gone thru the whole process repeatedly matters. Texas Mike made some great points about the type of dive differing. When someone looks at my logbook (a mentor, for instance) they are observing the variety of conditions & circumstances in which I have dove, not just the numbers or total bottom time. Other divers are loathe to recommend certain training programs or sites unless they have more details about a diver's history.

 

[Mike Newman]

I wouldn't get too worried about time under water. It's going to vary greatly depending on what your dive plan intended you to achieve, how deep it required you to go and other factors.

Just for the record, my average dive duration is currently about 35 minutes. My longest time (I dive on air only) runs out at some 48 minutes.

Incidentally, I believe (but someone, I'm sure will correct me if I'm off the mark) that PADI qualifying dives have to be in excess of 20 minute duration.

MN

 

[g2]

Originally posted by Mike Newman
Incidentally, I believe (but someone, I'm sure will correct me if I'm off the mark) that PADI qualifying dives have to be in excess of 20 minute duration.

All the certifying agencies seem to have minimum standards for how long a dive must be, how deep, etc., but isn't that for the purposes of classes and teaching?

IMHO a log book is for you, and you should log what ever you like. Short dives? You bet! Shallow? Of course! Want to log pool dives? Why not! It's your log book.

Yesterday I logged a 30 minute dive with a maximum depth of 6 feet. Why bother? Because I spent the whole time practicing OOA, equipment adjustments and emergency procedures, which is important to me.

Have fun with it!

g2

 

[Rick Murchison]

In diving we pay by the dive.
In flying we pay by the hour.
Therefore, we log dives and flight time.
Neither is a very good indicator of experience or competence, but both are better than nothing.
Rick