I need help re: practicing safety stops in a pool

[Juardis]

I need help. And a lot of practice. My wife and I took our OW certification dives yesterday and I seriously screwed up my safety stop. We were at 30' for about 20 minutes when our instructor called for us to surface and stop for a 3 minute safety stop. So I ascended to 15 feet....and kept ascending. I was going slow (maybe not slow enough), breathing continuously, but I couldn't stop. I hit about 4', then remembered to dump all my air. So I sunk....down to 25 feet. I'm trying to control my buoyancy by breathing only (no BC inflates/deflates) so I'm breathing frantically trying to control my ascents/descents. I wound up having to use the inflator button anyway, which probably contributed to my problems.

Anyway, long story short, I spent about 5 minutes yo-yoing between 5 feet and 25 feet until my ears wouldn't clear. So finally I slowly surfaced.

On our 2nd dive we stayed at about 20 feet the entire time so it was relatively easy to maintain our safety stop at 15 feet, but going from 30 to 15 proved more difficult than I anticipated.

So here's the question. How do you practice this in a 15 foot pool? Or can't you?

 

[EastEndDiver]

You can pick any depth you want to practice considering you only have a 15 foot pool.I mean to say choose ,lets say 10 feet,and try to maintain that depth for 3 minutes.The object is to "hover" in a controlled fashion at what ever depth you need/choose.Whether you practice at 15 feet or 10feet or 5 feet it will still give you the opportunity to Practice.

 

[Juardis]

Thanks EastEnd. I haven't had any trouble hovering or controlling my ascent in 15 feet of water, but then again, I don't have any air in my BC at 15 feet. Maybe add weight so I have to use air in my BC to maintain neutral buoyancy at 15 feet? Would that work so I could try stoping at, say, 7 feet?

 

[RTee]

Keep in mind that pressure doubles or half within the first 33 feet which means that volume will be inversely affected. For such a change, lungs by themselves no longer compensate...you also need to equalize your BCD accordingly, ie let some air out (under control) as you slowly come up and then add air in the same fashion as you slowly go down (and equalize your inner ears, drysuit squeeze, etc).

Properly weighted not only means that you can still hover at 15 ft (safety stop) on a near empty tank but that you will also be able to ascend to the surface in a controlled fashion.

In terms of practice in a pool, you should be able to hover at 15 ft then come up slowly (breath and BCD controls) and stabilize at 10 ft and then repeat the process at 5 ft, etc

 

[The Chairman]

Few, if any, hit their stops on their first dives. Depth control takes PRACTICE. If I might offer some insight: dump or add less air and WAIT. Go through a breath cycle or two unless you are plummeting down or rocketing skyward. Overcompensating causes more problems than it solves. If you are on/near the bottom you'll find that a well placed finger will support your entire weight. Obviously, not touching the reef is best and if it's soft billowy mud its not going to help at all. But, practice makes perfect... just slow it down a bit.

 

[ScubaSteve1962]

I have buoyancy problems too, I practice alot in a pool, in the 12ft, and 3ft, swimming through hoops at 12, and hovering in the 3, here's a site that might help you. also padi has a peak performance buoyancy specialty course.

Scuba Buoyancy Masterclass 1of9 - Buoyancy Control for Scuba Divers -Scuba Tech Philippines

 

[Peter Guy]

It is very hard to practice this in a pool -- unless the pool is REALLY deep.

A few comments:

a. Breath control should be good for depth variations approaching +/- 4 feet -- beyond that 8 (approximately) foot window, air expansion/contraction will make your BC/Wetsuit/Drysuit change enough so that it will (probably) effect your overall displacement volume (buoyancy). Thus you WILL have to put some air into somewhere if you change your depth beyond that window.

b. The closer you are to the surface, the greater the percentage volume change in all of your non-rigid (i.e., NOT your lungs but your BC/Wetsuit/Drysuit) air chambers. So as you get closer to that 15 foot stop, you may well need to dump air from a chamber and then use your lungs (breath control) to fine tune it.

c. THIS TAKES TIME AND PRACTICE.

As far as I can tell, the only time this isn't relevant is when you are using NO buoyancy control devices other than your lungs such as the attached picture of me in the Red Sea -- no wetsuit, no BC, no Drysuit. I was weighted for neutral plus the weight of the air in my tank at the start of the dive -- otherwise, yes, you will have to vent on the way up and add air on the way down to stay neutral.

 

[divad]

c. THIS TAKES TIME AND PRACTICE.

View attachment 105885

Ouch.

 

[TSandM]

Peter's right -- the first thing that struck me in the original post was that OP was trying to control his entire ascent with his breath. You simply cannot do that, unless you have almost no air in the BC, and are wearing no, or extremely thin exposure protection. At some point, you are going to HAVE to use the BC to do what it does -- compensate for buoyancy losses, and for buoyancy gains.

A tip that helped me a lot came from a former SB member named Jonnythan. He told me to ascend a little and then EXHALE. If I stopped ascending, fine; if I didn't, I needed to vent my BC a little. This pretty much matched my strategies for descents, which was to put air in the wing every time I cleared my ears. Both will keep you close enough to neutral that you can use body posture and finning to hold position while you make other adjustments.

Another point -- make sure you know the location of everyplace you can vent gas from your BC, because if you end up swimming down, your inflator hose will not be a good choice.

And don't feel bad -- I did 50 dives before I successfully held a shallow stop, and today I hold a technical cert (which means HAVING to hold stops, even while being harassed in various fashions). If I can learn this, anybody can!

 

[dumpsterDiver]

Peter's right -- the first thing that struck me in the original post was that OP was trying to control his entire ascent with his breath. You simply cannot do that, unless you have almost no air in the BC, and are wearing no, or extremely thin exposure protection. At some point, you are going to HAVE to use the BC to do what it does -- compensate for buoyancy losses, and for buoyancy gains.

A tip that helped me a lot came from a former SB member named Jonnythan. He told me to ascend a little and then EXHALE. If I stopped ascending, fine; if I didn't, I needed to vent my BC a little. This pretty much matched my strategies for descents, which was to put air in the wing every time I cleared my ears. Both will keep you close enough to neutral that you can use body posture and finning to hold position while you make other adjustments.

Another point -- make sure you know the location of everyplace you can vent gas from your BC, because if you end up swimming down, your inflator hose will not be a good choice.

And don't feel bad -- I did 50 dives before I successfully held a shallow stop, and today I hold a technical cert (which means HAVING to hold stops, even while being harassed in various fashions). If I can learn this, anybody can!

Exactly, I have no idea why someone who was learning to dive would try to control an ascent from 30 to 10 feet without touching their BC. If you are wearing a wetsuit or dry suit, it will be impractical if not impossible and would serve no good purpose.

You want to use the BC so that it makes the ascent easy and effortless and you can breathe comfortably. Trying to do it all with breath control makes no sense at all. It is kinda strange that your instructor would not explain this to you.

The problem with trying to practice ascents in a pool is that you don’t have enough depth to really feel the expansion of the suit and the air in the BC….so you can hang fine neutral in the water column in the pool, but you are NOT changing depths much, so it is easy and you are not having to really deal with the root cause of all the trouble and yo-yo-ing.

I suppose if you want to practice this in the pool, you could deliberately wear like an extra 8 lbs of lead, which would give you an extra gallon of air in the BC (more than normal) and learning to manage this larger than needed bubble in the small depth changes in a pool would probably help you get the feel for how hard it is to manage the increase in buoyancy as you ascend a larger distance in open water (when correctly weighted). But, this will make you more likely to lose control of buoyancy in the pool and you should know the dangers associated with that.