Practicing Solo Diving

[HungoverDiver]

Breathing gas with a slightly elevated pO2 is a smaller risk than the immediate risk of drowning.

Furthermore, it's not like breathing pO2 > 1.6 will instantly put you into O2 tox. Obviously you'd begin ascending, and then be in a safe pO2 range (assuming no deco ceiling).

 

[mrdre]

Even with a catastropic failure, you are likely to have atleast one minute of breathing gas. Or you could do a free ascend to 80' before breathing EAN40. Personally, I would continue breathing the primary bottom gas until back gas tank(s) is fully depleted, and, then swap to the EAN40. Breathing gas with a slightly elevated pO2 is a smaller risk than the immediate risk of drowning.

And what's the advantage of having EAN40 in this case then? Why not just the same gas as primary bottom? Or... if EAN40 is used for deco, why not carry then 2 pony bottles: 1 - with bottom gas, use it to extend bottom time, and 2 - used for deco. In this case regardless of depth, you switch to your spare, ascend, switch to EAN40. Isn't it better? (I'm NOT an experienced diver, I'm not arguing, I'm just curious).

 

[Nemrod]

And what's the advantage of having EAN40 in this case then? Why not just the same gas as primary bottom? Or... if EAN40 is used for deco, why not carry then 2 pony bottles: 1 - with bottom gas, use it to extend bottom time, and 2 - used for deco. In this case regardless of depth, you switch to your spare, ascend, switch to EAN40. Isn't it better? (I'm NOT an experienced diver, I'm not arguing, I'm just curious).

Because a pony bottle is never used to extend bottom time. There is no need for a no deco/no overhead solo diver to encumber themselves with two pony bottles, I am not completely sold on the idea of any pony bottle for much of my solo, much less two.

N

 

[sportxlh]

Interesting, BC exchange, in the sand on dive 1 and in mid-water on dive 2, was part of my SDI Solo Diver training with Jupiter Dive Center in FL. I hadn't done this exercise for several years, ever since my regulator was bonking me in the head on a dive off the east end of Grand Cayman several years earlier. This was an appreciated added skill, much easier mid-water.

I do practice deploying my pony, even if I do not breathe off of it, and I do deploy my SMB, reasonably frequently, when drift diving in Jupiter.

I got certified at the same place. I use a similar routine making sure I have the 'muscle memory' to get to my pony's reg and my extra mask in my pocket. I also deploy the SMB and reel at depth on all my solo dives, so complete that procedure several times each month. I've only messed with taking off and donning the BC underwater once at blue heron bridge (shallow site) since getting the cert. I should probably try that a few more times.

 

[mick allein III]

Interestingly, the SDI Solo materials that I have do not teach/ suggest doffing and donning your gear. The text recommends dealing with entanglement by avoidance and multiple cutting devices. We're other people's materials different? Sounds like the training has a lot of variability.


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[drrich2]

Mick:

Can't speak for the formal training position off-hand, but consider this. If a diver accidentally blundered under an entanglement hazard and got his tank valve & 1st stage royally wrapped in old netting or maybe poking through a thin piece of rusted metal yet unable to come back out, and he couldn't see the problem, rather than reaching up cutting by feel, it stands to reason that disengaging from the BCD and turning around to see what needs cutting or working loose would be a wiser course of action.

I'd think something like that would be very rare, but it could happen.

I swam under a rope at a local quarry and got my tank valve caught once. I could've cut myself free, but I doubt they'd like their 'link between attractions' cut up unnecessarily. I got lose without cutting or doffing, but the option would be one more potential tool to use.

Richard.

 

[mick allein III]

Dr rich do you dive dry? Wet? Can you describe how you don/ doff gear to free yourself?


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[drrich2]

Never been in a dry suit. If I were on a dive boat, based on past practices, I'd probably be in a warm, tropical destination, wearing swim trunks and a 'Champion' brand long-sleeve shirt (that keeps the sun off me and quick-dries; sort of the shirt equivalent of swim trunks) but no wet suit, as long as the expected temp.s are all over 75 degrees.

What I'm talking about is, you're swimming along, and entangle your tank valve/1st stage in rope, netting, kelp, what-have-you. You feel up with your hands and are having trouble resolving the problem, as it's basically behind your head. I don't usually wear gloves but I imagine that could make it worse. Now, if the situation is one where your main body is not entangled, and you judge it highly unlikely that that's apt to happen, you could unclip your BCD straps and cummerbund, and ease out of it while keeping your regulator 2nd stage in your mouth, so as to turn around and face your tank valve/1st stage. This might let you get it lose, or at least cut precisely with less risk of slicing a hose.

Thankfully I've never had to do such a thing and hope I never need to, but in an entanglement situation, I want some options!

Richard.

 

[BrewsKampbell]

When I did the SDI solo cert my instructor tied rope around my first stage and tied me off to a platform, around 20ft, then had me remove my BCD to cut away the hazard. It's a good skill to practice.

 

[sportxlh]

When I did the SDI solo cert my instructor tied rope around my first stage and tied me off to a platform, around 20ft, then had me remove my BCD to cut away the hazard. It's a good skill to practice.

Didn't quite do that, but while in the Keys recently, practiced taking off and donning my BC on a shallow sandy area. I forgot to mention I'd be doing this to my dive buddy and he thought I'd lost my mind.