What happens when..

[jonnythan]

Say you're doing some deco at 30 feet on your bottle of 50% and your LP hose bursts, but you still have 15 minutes of deco obligation.

Since deco bottles only have one second stage, what do you do?

 

[Waterlover]

I'd probably just change my 20 ft bottle regulator over and use it. I might also use the tank valve to control the gas flow too or may switch out a back gas regulator. I might buddy breathe with my team mate. All kinds of options I guess allot depends on conditions and how bad the hose is really blown...... Might even pull out the duct tape from my pocket and patch it

 

[DiveTub]

Well I can think of a few options, not in order

Switch to your Backgas and complete the rest of your deco obligation on your Backup Air Tables. Provided you are following the rule of thirds you should have enough gas to finish the Deco.

Ask any other team mates if you can have their bottles once they have finished there Deco, you should all be using the same mix if diving in a team.

Send up a Yellow DSMB and ask the support diver to bring down some more mix.

Swap the Reg out with one from your backgas, last option I would do as it is a pain in the ass and an expensive service at the end of the day.

 

[Braunbehrens]

This is exactly why I usually carry two stages even though I could deco out on one. For bigger dives, I think support is mandatory.

When all goes well, the deco is shorter, which is a nice bonus.

I suppose you could deco out on backgas, but man, what a pain.

I wouldn't switch regs with the other deco bottle unless it was the last option, because if the water going through it screws up that reg, then you have no deco gas at all. Using your buddy's left over deco gas is a good idea, and once that bottle is empty you could swap that reg onto your bottle. You'll have to pay for his reg service of course.

I haven't actually tried this, has anyone here tried blowing water through a reg under water? I hear the trick is to keep the purge open while you pressurize the reg.

 

[DIR Tec Diver]

Primary Option

Switch immediately to your back gas or travel mix in case your back gas is hypoxic for your depth.
Have your buddy remove one of your regs and replace it on the deco bottle
Continue your deco, and your buddy now stays in the water with you to ensure that you do not have any problems

Removing and replacing a reg underwater will not hurt your reg and the air will blow out the water anyway. Also, your reg is the least of your worries.

Secondary Option

Use your backgas or travel mix while your buddy finishes off his deco, and at the same time identify surface support if possible. Once s/he is clean they switch to backgas and either bring you a new bottle or you finish off with their deco gas, and your buddy uses backgas/travel mix and stays with you for support.

However the primary option should always be done first.

Tertiary Option
If all hell breaks loose and all above options fail, you planned the dive poorly and are in a bad situaion. buddy breathing is an option, but not something to be done right away.


Lastly, this should never happen if you have a proper hose such as the Halcyon long hose, and you properly maintain your gear, but **** happens and the proper contingency plan will save your life.

 

[Diver0001]

jonnythan once bubbled...
Say you're doing some deco at 30 feet on your bottle of 50% and your LP hose bursts, but you still have 15 minutes of deco obligation.

Since deco bottles only have one second stage, what do you do?

It's a pretty unlikely event but you could take the reg off and replace it with one from your backgas unit. It can be done under water. It's not good for the reg but not finishing deco isn't good either.

R..

 

[Diversauras]

Is a burst LP hose something that happens regularly? Does anyone here have firsthand experience of this failure? In several thousand dives I have never had this happen though 15 years ago I did have a hose with bulge.

 

[Diver0001]

Diversauras once bubbled...
Is a burst LP hose something that happens regularly? Does anyone here have firsthand experience of this failure? In several thousand dives I have never had this happen though 15 years ago I did have a hose with bulge.

It's theoretically possible but you'll usually see it coming long before it happens. A typical LP hose can withstand something like 30 bar of pressure. That's 3 times what you normally find inside a regulator 1st stage. With that kind of pressure building up from IP creep the 2nd stage (downstream designs) will start to freeflow before your hoses burst.

So assuming you keep your hoses well maintained then you shouldn't actually ever seen this problem in practice.

What do you hear more often (although this is also in the realm of the highly unlikely) is that an HP seat failure inside the first stage causes a sudden and very vilolent free-flow, enough to blow the reg out of your mouth or even to cause a lung injury.

In all the time I've been reading scuba forums I've heard of this actually happening to 2 or 3 people. The only story I can remember about LP hose failure was from someone who had an LP hose burst and it gave him a nasty whack under his arm where the hose was routed. I don't know if this happened because of a reg failure or because he didn't check his hoses.

So I'd conclude that if you ever see it you should take pictures because you'll proably never see it again.

R..

 

[DIR Tec Diver]

Good post Diver0001

Also since you should have your hose pressurized prior to the dive and then turn the valve off, you can easily inspect the hose for any trouble areas. They are most likely to occur at the surface as the pressure in the water offsets some of the pressure exerted from inside the hose.

One trick I was taught by another DIR diver is when I do my gas switches especially with multiple stages (all on the left side right...;-) I breathe from the stage until I feel the hose go slack then I turn the valve open to allow the air to fill the hose and breathe from. This also double ensures that you are breathing from the proper tank and don't tox

 

[Doof]

When you guys talk about switching regs underwater, are you talking about the first stage?

Does this imply that your backgas and your stage\deco bottles are all using the same type of valve (din or yoke)?

Or are you talking about removing the hose from the first stage and attaching that to the deco bottle?