Bottom Time, beginner question

[Mike Majoris]

Just wanted to ask real quick if bottom time is a consideration when diving in extremely shallow depth in a swimming pool. I was testing out some new gear over the weekend and spent a lot of time underwater but only in 6 - 8 ft. Is it fine to essentially spend all day down there or do you still have to watch how long you're under? Naturally, the gas will last a very long time doing this so I was curious.

 

[TMHeimer]

I believe it is either 18' or 22' the depth that you could stay down indefinitely (air permitting) and ascend directly to the surface with no decompression stops. I guess the ongassing and offgassing pretty much cancel each other out at that depth. There is probably a more in depth explanation.
I routinely dive to 20-30', doing 2 dives in a day and not worrying at all about my residual nitrogen.
I do my written profiles for such dives when they're done (just for my log book)--not a practice I'd advise. If I'm doing dives deeper than that I will do the profile beforehand and stick to the plan.

 

[formernuke]

Just wanted to ask real quick if bottom time is a consideration when diving in extremely shallow depth in a swimming pool. I was testing out some new gear over the weekend and spent a lot of time underwater but only in 6 - 8 ft. Is it fine to essentially spend all day down there or do you still have to watch how long you're under? Naturally, the gas will last a very long time doing this so I was curious.

It is totally dangerous to spend that much time underwater......unless I'm with you.

Welcome

 

[Scuba Lawyer]

spent a lot of time underwater but only in 6 - 8 ft. Is it fine to essentially spend all day down there

From a nitrogen clock standpoint, yes.

 

[Esprise Me]

Really, as a beginner you'd have a hard time exceeding the NDLs on a single tank down to about 60 feet before running low on air. Just remember that a rapid breath-hold ascent can still kill you even at pool depths. Don't worry about your bottom time in there, but still come up slow and exhaling.

 

[broncobowsher]

Considering that 10' is generally the shallowest stop made, you never get deep enough to get to that stop.
You will run out of air before anything else.

 

[Mike Majoris]

Ok, I thought so but I also try to adhere to "The only dumb question is one you dont ask" practice. I've done my aow and am doing my rescue diver now but never thought to ask about something that seems as silly as sitting on the bottom of a pool.

I was mostly doing it because during this covid stuff I was desperate to get underwater but I also wanted to try out my new reg and bcd. I didn't realize how valuable getting used to the new gear in a pool would be. I feel wayyyyy more confident with it all now and am really glad I played around and spent all that time down there.

I burned through 2 bottles of air in 2 days in the pool if that gives you any indication on how long I was staying down, lol.

Also, worth noting, if you're really itching to dive but can't, turning all the lights off and hovering at 6 feet in a big pool can help you imagine you're somewhere cooler.

Thanks for all the replies!

 

[ScubaWithTurk]

I didn't realize how valuable getting used to the new gear in a pool would be. I feel wayyyyy more confident with it all now and am really glad I played around and spent all that time down there.

ALWAYS get give new a gear a go in the pool before taking it on a dive. I find that it allows me to rework my weighting (if needed) and also lets me become more familiar with the ins and outs of it prior to be someplace much less forgiving such as the ocean.

Glad to see you are getting some time underwater but have to admit I am jealous.

 

[moose_grunt]

Even the Navy’s shallow table starts at 30 ft, and you get 371 min no deco time for that.

 

[Angelo Farina]

At such shallow depths the risk of decompression-related injuries is totally zero.
But this does not mean that there are no other risks.
The main risk is caused by the fact that you are breathing very dry air, and you are not drinking.
Staying hours in these conditions can cause two adverse effects. The first is the most obvious, your throat and mouth will become extremely dry, causing irritation and favouring the attack of bacteria.
The second is even more insidious: if you stay almost still for hours breathing dry air, you will loose a lot of water, your blood will become ticker, and you risk a Deep Vein Thrombosis (DVT) exactly as staying 6 hours or more trapped in the seat in economic class on an aircraft.
This happened to me in a long flight, and I risked my life, so now I am very cautions not to come again in the conditions which favour DVT.
If you plan to spend hours breathing compressed dry air in the bottom of a pool, I recommend you hydrate yourself periodically (every 30 minutes), drinking a lot of water, keep your legs and body moving (swimming around) . Substantially the same recommendations given to aircraft passengers on long-haul flights.