Emergency bailout strategies for recreational diving

[fdog]

I'm sure you could plunk a H or Y valve on your cylinder, but the OP was looking for recreational answers.

All the best, James

 

[MRadke]

I'm sure you could plunk a H or Y valve on your cylinder, but the OP was looking for recreational answers.

All the best, James

I also am thinking in terms of recreational diving. I already own the Y valve and with all the talk of bail out bottles and redundancy I can't help but think that it would make a good solo rig, without the expense of doubles.

 

[rx7diver]

I also am thinking in terms of recreational diving. I already own the Y valve and with all the talk of bail out bottles and redundancy I can't help but think that it would make a good solo rig, without the expense of doubles.

MRadke,

I think having a Y- or H-valve addresses some situations in rec diving, but not all. For example, when diving in very cold water with a BC and a drysuit (and using your BC for buoyancy, rather than your drysuit), a Y-valve allows you to inflate your BC from a different 1st stage than your primary 2nd stage uses. This should decrease the risk of regulator freeze up on your primary regulator. And this also prevents the loss of BC buoyancy control if your primary reg should need to be shut down after it begins free-flowing from freeze-up.

However, catastrophic loss of gas can occur due to other than regulator freeze-up, that having a Y-valve can't help much with.

Having a Y-valve does not replace having independent doubles or having a bailout bottle.

Safe Diving,

Ronald

 

[coldwatercanada]

I have not heard a report from anyone taking an intro to tech from any agency,

PADI now has one and so does TDIC i believe?

 

[Fish in a Barrel]

Thanks for the clarification, guys.

 

[DaleC]

fdog, thanks for the well thought out response. Another reason for bailout that I consider is if I am suddenly feeling physically/mentally wonky in some sort of way. I'd rather deal with that sort of thing on the surface or at least in a more shallow zone.

Rx7 addresses the value a Y/H valve can have for duplicating regulators but it only gives you one air (volume) source. So, if you have a failure that results in a breach below the 1st stage (extruded tank or valve O ring or blown burst disc) or an unstoppable free flow you will lose all your gas. With two tanks and proper gas planning you should be able to lose one system and still be able to ascend properly.

 

[dumpsterDiver]

fdog, thanks for the well thought out response. Another reason for bailout that I consider is if I am suddenly feeling physically/mentally wonky in some sort of way. I'd rather deal with that sort of thing on the surface or at least in a more shallow zone.

Rx7 addresses the value a Y/H valve can have for duplicating regulators but it only gives you one air (volume) source. So, if you have a failure that results in a breach below the 1st stage (extruded tank or valve O ring or blown burst disc) or an unstoppable free flow you will lose all your gas. With two tanks and proper gas planning you should be able to lose one system and still be able to ascend properly.

NO, the y-valve is specifically designed to stop an uncontrollable free flow. A free fllow is a relatively common event, while blown burst discs, extruded neck O-rings etc. are pretty rare especially at depth after a considerable portion of the air has been used.

 

[AfterDark]

I also am thinking in terms of recreational diving. I already own the Y valve and with all the talk of bail out bottles and redundancy I can't help but think that it would make a good solo rig, without the expense of doubles.

Wouldn't help much if say the burst disk on the valve let go, rare I know but it does happen. Last June one let go on one of my tanks. Granted it was overfilled by the LDS and was sitting in the backroom when it happened but, it could have just as easily been on my back @ 130'. IMO ID's are the closest we can come to a fail safe system. When I configure ID's they are just 2 tanks without manifolds in double bands mounted on a BP with a reg on each valve. I can use them as singles or ID's so the expense is not so much. Also much easier to carry one tank at a time.

 

[DaleC]

You are correct DD. I typed too fast there. What I should have said was that a freeflow could leave one with too little gas reserve if not addressed quickly enough. My mistake.

 

[Akimbo]

I think it depends on how you use IDs (Independent Doubles). If the second cylinder in your doubles pack is treated as a pony bottle and not used at all except in an emergency I agree. That also requires surfacing with the same reserve gas you would when diving a single.

On the other hand, I believe you can achieve a slightly higher level of security with an isolation manifold when your procedure normally uses both cylinders — providing you leave the isolation valve normally shut. The technique I learned as progressive equalization provides the majority of advantages of IDs with all of the advantages of an isolation manifold.

The price you must pay includes the inconvenience of periodically reaching back to open and reclose the isolation valve to equalize cylinders, greater hassle breaking them back down to singles, and introducing two potential failure points on the valve (where the plug or isolation valve install) compared to a dedicated K-Valve. Both methods allow using the second cylinder as a hard reserve… sort of a higher volume and much more reliable J-Valve.

It all depends on your dive profile, how much prevention against pretty rare failures you desire, and how much you are willing to carry. I just got through building a set of double LP-45s with an isolation manifold as part of my current response to this compromise.