Swapping to new mouthpiece U/W?

Michael Thornton

Michael Thornton

Rebreather Enthusiast
Ever since a discussion between some fellow instructors and my Inspo/Evo IT about rebreather accidents and causes. (We were discussing possible scenarios, how to prevent and how we would respond) I have been thinking about mouthpieces. I know some people that have had serious problems due to a torn mouthpiece. Primarily floods etc. So I wanted to ask if anyone had ever tried carrying a backup mouthpiece and if needed switching during a dive.

First off I know that "check your mouthpiece" is on your checklist and the easiest thing to do would be change out a bad mouthpiece prior to diving. But what if it looked good before the dive and tore during the dive?

I know most modern Rebreathers are flood tolerant and typically have a way of draining water either out of the can or the exhalation counterlung. But this wastes both dil and O2. Also on all of the rebreathers that I currently dive the best position to be in in case of a flood is head up which is not always possible in a cave exit.

So I have been kicking around the idea of carrying a backup mouthpiece on serious dives. Has anybody else done this? How did it go? How hard was it to remove the old mouthpiece? Did having a new tie wrap that is not trimmed bother you?

I am uploading 2 images. The first shows a mouthpiece that is tearing. 2nd picture shows the bad part of just trying to rip it off. The tie wrap stayed on. (I know the pics are not of a BOV because I didn't want to rip my mouthpiece on my BOV for demonstration)

I am curious whether you guys think bailing out and fixing the mouthpiece and then going back on is an option or a waste of time. If it is an option how would you go about doing it? :shrug:
 

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I've heard several people say they carry a spare and zip ties to go along with it. I wouldn't screw around with it. Just rip the damn thing off and stick your mouth over the remaining stub. You won't be able to bite down much, but you can keep it in your mouth. It happened to me and I finished the dive just fine without the need to bail out.
 
kwinter said:
I've heard several people say they carry a spare and zip ties to go along with it. I wouldn't screw around with it. Just rip the damn thing off and stick your mouth over the remaining stub. You won't be able to bite down much, but you can keep it in your mouth. It happened to me and I finished the dive just fine without the need to bail out.
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Ken,
Just curious how long was the dive after you bailed out? I am thinking of this mainly for long deco hangs or long cave exits and am worried about being able to bite on it with no mouthpiece for that long. Maybe I should experiment.
 
You should be able to bail-out to a staged cylinder then use a knife to cut the cable-tie. This could be awkward due to it's being just under your chin, but should be manageable, or a buddy could help.

The biggest thing to make this a problem would be due to the corrugated hoses holding the BOV about a foot from your chin at best so restricted reach and restricted vision.

I never thought of carrying a spare mouthpeice...I carry lot's of stuff that is far more useful, spare mask, torches, wet-notes, reels etc, all have been used a few times in the last few years, I can't see a need for cluttering my pockets more and if I did there are other things I'd sooner have. If I had mouthpeice problems I would probably opt between OC when busy and sealing my lips round whatever is left of the mouthpeice when I have a hand free and suffer the uncomfortable deco.
 
Michael Thornton said:
Ken,
Just curious how long was the dive after you bailed out? I am thinking of this mainly for long deco hangs or long cave exits and am worried about being able to bite on it with no mouthpiece for that long. Maybe I should experiment.
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I went about another 5-10 minutes before I decided that it was dumb to continue racking up more deco time with that kind of failure. Total time sucking on the mouthpiece instead of biting was probably 30-40 minutes.
 
So if you guys had a tear such as the one in this picture you would go ahead and rip it off and bite onto what was left for the remainder of the dive?

I know OC BO is always an option but as a Cave Diver I try to find ways to stay on the loop as long as possible.
 

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I don't care what the rip looks like. If I'm sucking water, I wouldn't hesitate to rip it off. If not, I probably wouldn't know it was ripped.
 
Michael Thornton said:
So if you guys had a tear such as the one in this picture you would go ahead and rip it off and bite onto what was left for the remainder of the dive?
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I'd probably leave it on as something to grip with the teeth, but push the whole thing further back into my mouth so my lips seal past the tear. If that doesn't work bail out, take a look and figure out what to do. Maybe tear it off and always hold the BOV to your mouth or go OC as and when you need both hands.

You should end the dive at that point, and should have enough bailout to get you out, so you should easily have enough gas to arse around and work out what is the most comfortable way to stay on the loop. All assuming there are no other problems.
 
I'd probably do it on deco. (Normally get bored and have been known to get tools out and fix all kinds of stuff) I carry spare zip ties anyway and I could rob a deco stage of a mouthpiece. Nothing to lose at that point though - if you can't fix it no matter.

So the more interesting question is whether I'd exit the cave when I discovered the fault. Without doubt yes. I wouldn't stay there racking up deco trying to fix it. I wouldn't extend penetration with a known failure. So turning, bailing out if sucking water and fixing on deco are the options I'd take.

(If it was a 6 meter Mexican cave, i was halfway through a 3 hour penetration and I had full bailout I may try to fix it there and then. But that's academic as I wouldn't use a RB for that)
 
I know people who take a spare and there was an incident where Rich Stevenson had the entire mouthpiece come away while scootering and ended up with it in his teeth while the loop was washed behind him out of reach. Was a deep one from recall as well.

Thinking about it, of the 4 cutting devices that I usually have on me none of them have a point or tip suitable for getting under a tie-wrap.
 
(toungue firmly in cheek)

Sounds like a few people ought to dive Alpinist for a year..... By doing so you will learn the Ten P's of Rebreather Success (or you'll be dead, take your pick)

Which is to say that:

Proper
Prior
Predive
Procedures
Positively
Prevents
Piss
Poor
Postjump
Performance


A little preventative maintenance predive wouldn't hurt. I change mouthpieces yearly, and also use a bit of crocus-cloth (gentle abrasive cloth, don't know if "crocus cloth" translates unleverally) to smooth the sharp edge that is usually what cuts a mouthpiece.

Fixing my gear *on* a dive shows some organic weakness in my predive procedures.... sort of like changing a fuel filter in flight on a jet. Is it because you forgot to do it in January when it was scheduled? Of because it was damaged in transit and you didn't inspect your gear before the dive? In any event it was broken before you jumped... shame on you.


Dave


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Dave Sutton said:
...don't know if "crocus cloth" translates unleverally.
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I'd call that Emery cloth or Wet&Dry. Not sure I could translate 'unleverally' though ;)

FWIW, I carry a spare mouthpiece and ziptie since hearing of Izzy's woes spending 2.5 hours decoing without one. It takes up next to no space and if I've got a long hang, what else is there to do besides listening to some choons and staring at my buddy's ugly face?
 
Dave Sutton said:
(toungue firmly in cheek)

Sounds like a few people ought to dive Alpinist for a year..... By doing so you will learn the Ten P's of Rebreather Success (or you'll be dead, take your pick)

Which is to say that:

Proper
Prior
Predive
Procedures
Positively
Prevents
Piss
Poor
Postjump
Performance


A little preventative maintenance predive wouldn't hurt. I change mouthpieces yearly, and also use a bit of crocus-cloth (gentle abrasive cloth, don't know if "crocus cloth" translates unleverally) to smooth the sharp edge that is usually what cuts a mouthpiece.

Fixing my gear *on* a dive shows some organic weakness in my predive procedures.... sort of like changing a fuel filter in flight on a jet. Is it because you forgot to do it in January when it was scheduled? Of because it was damaged in transit and you didn't inspect your gear before the dive? In any event it was broken before you jumped... shame on you.


Dave


.
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Dave,

I think your observation about pre-dive checks is important and it goes without saying that it is a VERY critical part of the planning/pre-dive sequence.

That said, things do happen and I don't believe there is any harm in discussing hypotheticals especially when it comes to safety issues. I always try to beat into my students heads that I am trying to help them become "thinking divers". In the scenario that Michael has outlined in his post, simply saying "It should have been caught in the pre-dive check" doesn't really help a diver who now finds himself in a very difficult situation during the "dive" portion of his dive.

Just like a ruptured hose, leaking hose crimp, failed dump valve, faulty BOV, sticking MAV, etc. etc. things go bad and unfortunately, can not always be identified during a pre-dive check. This is exactly why we train to deal with emergencies during the dive portion of the dive. This does not imply that we do not do our regularly scheduled maintenance, pre-dive checks, in-water checks, etc. etc., but only that sometimes in spite of the best of preparation and intentions, things go pear shaped and the better equipped and prepared we are to deal with them, the more likely we are to survive the event.

My motto is, "prepare my equipment as though my life depends on it and dive my equipment as though an idiot prepared it!" (Most likely true in both cases! :crossfing)

Warm regards,
Randy
 
Well then: We better carry a spare BC hose, a spare second stage hose, several tie wraps, a mouthpiece, two wrenches (at least), might as well toss in a new O-ring spool for a HP guage, since we all know that they are famous for leaking (or why not a spare HP guage?), several first stage plugs (both sizes) and an allen wrench, a spare mask strap so you can change that too (while using your spare mask to see), and a "dive shop open, repairs performed" sticker on the back of your rig.

Or you could just maintain your gear on the surface to start with... :brickwall


But: :idea: !!

I can clearly see holding onto the superstructure of the Doria, on open circuit, changing out my mouthpiece while wearing 3 finger mitts... (not)....


Dave


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nickb said:
FWIW, I carry a spare mouthpiece and ziptie since hearing of Izzy's woes spending 2.5 hours decoing without one. It takes up next to no space and if I've got a long hang, what else is there to do besides listening to some choons and staring at my buddy's ugly face?
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I tend to agree. Not very big. I wouldn't really notice it in pocket. And I do not think I would add that much to my deco to change it out. If I was worried about that I could wait till I got shallower to change it.

What do you use to remove the old mouthpiece?




Sent from my iPhone using Tapatalk
 
Dave Sutton said:
I can clearly see holding onto the superstructure of the Doria, on open circuit, changing out my mouthpiece while wearing 3 finger mitts... (not)....


Dave
.
Click to expand...

Dave
Thanks for posting I honestly wanted to get a feel for why people do and do not do it. I was curious about their reasoning whether they are for or against it. I am not saying everyone should. And I agree there are times where it would just be stupid to be fiddling with it underwater. (ie high current with thick gloves etc) but I also think just because I have it in my pocket doesn't mean I would have to use it. It would just be another option.

Funny you should mention it I carry a wrench and HP port. Haven't had to use it yet but it is super small. :-). I do get made fun of a lot for that one.



Sent from my iPhone using Tapatalk
 
Dave Sutton said:
Well then: We better carry a spare BC hose, a spare second stage hose, several tie wraps, a mouthpiece, two wrenches (at least), might as well toss in a new O-ring spool for a HP guage, since we all know that they are famous for leaking (or why not a spare HP guage?), several first stage plugs (both sizes) and an allen wrench, a spare mask strap so you can change that too (while using your spare mask to see), and a "dive shop open, repairs performed" sticker on the back of your rig.

Or you could just maintain your gear on the surface to start with... :brickwall


But: :idea: !!

I can clearly see holding onto the superstructure of the Doria, on open circuit, changing out my mouthpiece while wearing 3 finger mitts... (not)....


Dave


.
Click to expand...

Dave,

I prepared an equally snarky response to the above, but then thought the better of sending it! Suffice it to say that your above comments are less than helpful.

As I mentioned earlier, preparation prior to the dive will avoid 99% of all underwater equipment problems, but stuff happens and within the realm of common sense, IMHO it makes sense to be prepared with items that can easily be switched out underwater when appropriate. Obviously, as an active CCR cave diver, streamlining and minimalist approach to equipment carried is an important component for me. That's why I say "using common sense".

Regards,
Randy
 
Randy Thornton said:
Dave,

I prepared an equally snarky response to the above, but then thought the better of sending it! Suffice it to say that your above comments are less than helpful.
Click to expand...


Your opinion. Not mine. Or anyone I dive with, as none of us are going to try to fix equipment underwater. Then again, we dive in a different environment. I'd remind you that 99% of diving is not cave diving...

Your son asked for opinions, not validation of a pre-existing decision. You got mine.



Dave

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