swapping 1st stages while at depth; emergency only

[AquaticLung]

Hey everyone,

This is a hypothetical, extremely rare, emergency situation that I've been thinking about lately. If you were diving side-mount (dual independant tanks and regs) and a catastrophic failure occurred that rendured one of the regulators useless (say; an o-ring failure on the inlet of the 1st stage), but the tank and tank valve were fine, leaving you with two tanks with air and only one regulator operational. Would the following be possible: (Only looking for facts regarding regulators)

Would a regulator operate normally, or at least sufficiently enough to prevent one from drowning, after removing the functioning 1st stage from the tank that has been breathed out and inserting it into the valve of the tank that still has gas, opening the valve and purging the system with air?

This would only be an option if there were no chance of making it to the surface in time with the air left in the functioning tank and regulator (deco, entanglement, cave dive, etc)

Without all the opinions like, "you shouldn't put yourself in that position", or "why would that ever happen", could some of you please inform me as to whether or not a regulator would function after the interior has been exposed to water and then repressurized while still full of water. I realize that the SPG will be ruined and even possibly the entire system, but in an extreme case would this method suffice as a feasable option OR would I be better off just breathing directly from the tank valve?

Please forgive me for the remarks about "not looking for opinions" as I'm always looking for helpful opinions, but more than often I read these threads and there is unprovoked or undue criticism and condescending words written. Thanks for your replies and good diving to all!!!

JD

 

[cerich]

This is a great example of why i feel as an tech Instructor that tech divers need to have a good understanding of their gear.

They will work fine, you will want to service them asap to prevent corrosion issues down the road and quite possibly your spg will have a shorter lifespan, it's very unlikely to get ruined, look at the size of the holes in the first stage, hose... how much water you think is gonna move thru that?

Press your second stage purge when you pressurize the system

 

[Cave Diver]

This is a great example of why i feel as an tech Instructor that tech divers need to have a good understanding of their gear.

They will work fine, you will want to service them asap to prevent corrosion issues down the road and quite possibly your spg will have a shorter lifespan, it's very unlikely to get ruined, look at the size of the holes in the first stage, hose... how much water you think is gonna move thru that?

Press your second stage purge when you pressurize the system

Agreed.

 

[Cave Diver]

BTW, one thing to keep in mind is that during the time of swapping your one working regulator to the other tank, you're going to be without ANY working regulator.

 

[Jim Lapenta]

Mike Nelson did it all the time.

 

[ianr33]

BTW, one thing to keep in mind is that during the time of swapping your one working regulator to the other tank, you're going to be without ANY working regulator.

Yep, would rather try this trick if I had a stage on me as well. i.e 3 tanks total.

Or I suppose a Spare Air would work as well.

 

[BgDadddy]

I've heard about people doing this. Personally, I don't think I could hold my breath that long. In that situation though, I reckon you just have to give it a shot.

 

[Cave Diver]

Yep, would rather try this trick if I had a stage on me as well. i.e 3 tanks total.

Or I suppose a Spare Air would work as well.

Yeah I was gonna suggest something along those lines, but since he stated he only wanted to know whether a reg could be swapped, I refrained from posting better solutions.

 

[TSandM]

I know somebody who was on a tech dive when one of his buddy's deco regs blew up -- the diver calmly switched regs off the other deco bottle.

As already said, you have to service them if you do that, and the pressure gauge will be ruined.

 

[tbone1004]

You can always bare tank breathe while you're switching regs. Up until relatively recently, the NCSU scuba program required their open water students to descent to 13 feet, remove the first stage reg from the tank, open the tank up, flip the HP seat on the piston, reassemble and put the regulator back on the tank. You had a paperclip and that's it. The SPG's were fine, but this was chlorine not salt water... No damage to the regulators at all, there isn't a whole lot of anything inside of them. With salt water you'll want to service them for corrosion, but it won't damage any parts. It's metal, springs, and O-rings for the most part with some teflon for the seats...