Stuck BCD Inflator

Please register or login

Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.

Benefits of registering include

  • Ability to post and comment on topics and discussions.
  • A Free photo gallery to share your dive photos with the world.
  • You can make this box go away

Joining is quick and easy. Log in or Register now!

richmonddiver

Contributor
Messages
97
Reaction score
35
Location
Richmond, VA
# of dives
50 - 99
Hi everyone,

I read on another thread about a diver who is believed to have died as a result of a stuck inflator. The solution to this is, of course, to disconnect the inflator. I was under the impression that the left shoulder dump was engineered to vent air at least as fast as the inflator can supply air. That is, if you pull on the power inflator to activate the left shoulder dump, you should not be able to inflate the BCD. Is this correct? I don't have a tank, or I would try this myself.

If the above is correct, it would seem to me that pulling down on the inflator to vent air would put both hands in the area where they are needed. One hand to dump air and manipulate the inflator, and the other hand to get the hose removed.

I can also see the situation where someone who is under stress pulls the inflator too hard and rips the inflator off of the BCD.

Thank you for you help.
 
I can also see the situation where someone who is under stress pulls the inflator too hard and rips the inflator off of the BCD.
Wouldn't have to worry about the BC over inflating at that point would they? Sorry couldn't resist.

I've tested this on a few BC's during OW training sessions with students since disconnecting a LP hose is part of the courses I teach.
What I have found is, most inflators will vent almost as much as what's going in. The ascent is pretty gradual.
The shoulder dumps will keep up for the most part.

I'm not saying this is always the case, but most of the time when an inflator sticks during a dive it inflates less than had the button fully stuck. It's important to test the inflate and deflate buttons pre-dive during setup.
 
Another solution would be to fin downwards while dumping from the rear dump.
 
Hi everyone,

I read on another thread about a diver who is believed to have died as a result of a stuck inflator.

Do you know what the cause of death was? Because stuck inflators don't kill people. At most, if the diver is unaware of how to deal with it, it could cause a fast ascent.

Something about the ascent must have killed the diver. In the context of recreational diving it's highly unlikely that a diver who makes a buoyant ascent would get *such* a serious DCS hit that it kills them. Moreover, a DCS hit of that nature is not immediate and there are possibilities to treat it. A fast ascent is obviously bad but seldom fatal.

For example, a buddy of mine once had a drysuit inflator stick wide open and was unable to get the hose uncoupled (I'm not 100% convinced that he tried) or to vent the suit fast enough to stop an ascent. I think he may have tried to do both at the same time and did neither correctly. The incident started fairly deep, at about 25m and thankfully it was early in the dive. He said that when he broke the surface he came out of the water to his hips. That's how fast the ascent was. He was not injured although he was shaken, so we did put him on oxygen and he was out of the water for a few days after that.

The most obvious thing that I can think of that would cause a diver to die from a stuck inflator would be holding their breath during the ascent. If my buddy with the drysuit had done that from 25m he would have been dead before the other 2 of us got to the surface.

A less obvious scenario would be that the diver threw out his regulator (equipment rejection) in response to the unexpected event and drowned. As an instructor I can assure you that students do things like that. In the past, for example, I've seen a student in the pool throw out their regulator and rip off their mask because they got some water in their nose while learning to clear the mask. This is also optional behaviour that is trainable. The question is if the diver in question had a history of this and whether or not it was addressed adequately.

See what I did there? By putting a little logic into it, you can break it down. A stuck inflator is only the trigger for a response. It's the response that you have to worry about.

Your concern seems to be that a stuck inflator will put you at risk of death. No it won't. It will, at most, give you a free ride to the surface if your response is to "flare and exhale".

Modern BCD's are also engineered to be able to vent at least as fast as they can fill. So another response could be to go vertical, vent the BCD and continue to vent it until you get the hose uncoupled. The shoulder dump will do but any vent will work. The main objective is to vent AND get the hose uncoupled.

What I notice in the OW course is that getting the hose uncoupled isn't obvious to a lot of people and requires some practice. So...... practice it. At the end of most dives you have a safety stop which is an ideal moment during every dive where you can practice stuff.

They say practice makes perfect and they're right. Since I started teaching I think my basic skills have improved 1000 fold. I do things on a regular basis now that I never bothered practicing before I started teaching. If you're not an instructor then you don't get the benefit of this constant repetition so use your safety stop productively.... That would be my advice.

R..
 
Some BCD / wings don't have pull dumps. I don't like to train emergency responses that are equipment dependent (muscle memory) so my procedure is:

Empty lungs as far as possible. Reduces buoyancy and risk of LOI. I also teach that the first response to ANY increase in buoyancy is to exhale.

Left hand raise hose as high as possible while pressing the deflate button. Since gas goes up, the injected gas will bubble straight out of the oral inflate mouthpiece.

Right hand reach across and disconnect LPI hose.

Left hand remains on inflator assembly in order to facilitate additional dumping or bring mouthpiece in for oral inflate.

Right hand check depth gauge / PDC and adjust as required.

Once neutral, reconnect with team and go through the necessary (ascent, navigation to line etc)

If viable, pad safety stop as long as practical dependent on how far the initial ascent was, initial depth and how far into the dive you were.
 
Thanks everyone for their replies.

Diver0001: Yes. I am aware that a stuck inflator will not directly kill a person. I am sorry I misspoke. I don't know for certain why they died. The immediate cause of death is not a concern for me.

My concern was the proper procedure to decouple the hose, if a stuck inflator event did occur. The discussion on the other diver's death was a catalyst for asking the question. The common response for a stuck inflator is "uncouple the hose". That's great advice, but how to do so would be much more useful.

Knowing that a BCD can vent air at a rate about as fast as it can fill takes a difficult situation and makes it much less stressful. How many new divers are actually aware that a BCD can dump air about fast as it fills? I could probably pull both of my shoulder dumps and go negatively buoyant even with a stuck inflator.

I think it makes the most sense to pull down on the inflator assembly and activate the jet dump, while simultaneously disconnecting the hose. It puts both hands where you need them. Having both hands in the immediate vicinity would facilitate removing the hose. Removing a hose under pressure is a technique that requires some practice, as Diver0001 mentions.

I presume that other dumps could be used, like rongoodman mentioned. I know I lack the agility to simultaneously activate the kidney dump and remove the hose while wearing thick gloves. I probably couldn't do it without gloves.
 
Some BCD / wings don't have pull dumps. I don't like to train emergency responses that are equipment dependent (muscle memory) so my procedure is:

Empty lungs as far as possible. Reduces buoyancy and risk of LOI. I also teach that the first response to ANY increase in buoyancy is to exhale.

Left hand raise hose as high as possible while pressing the deflate button. Since gas goes up, the injected gas will bubble straight out of the oral inflate mouthpiece.

Right hand reach across and disconnect LPI hose.

Left hand remains on inflator assembly in order to facilitate additional dumping or bring mouthpiece in for oral inflate.

Right hand check depth gauge / PDC and adjust as required.

Once neutral, reconnect with team and go through the necessary (ascent, navigation to line etc)

If viable, pad safety stop as long as practical dependent on how far the initial ascent was, initial depth and how far into the dive you were.

I do something very similar but I teach students to tightly wrap their 2nd, 3rd and 4th fingers around the LP hose and to PUSH it in the direction of the coupling (compress the pressure coupling). This makes it much easier to release because the pressure has been neutralized. The thumb and forefinger pull the sleeve back on the LP hose and the pressure in the hose just pops it off.

Getting people to understand why you need to grab the hose with only their 2nd, 3rd and 4th fingers seems to be the main complication. In order to impress upon them how well this works I ask them to try it without. The difference in how easy it is, is immediately obvious. Many students, especially those who aren't accustomed to "man handling" their gear, (children, people who have grown up pampered and have never done manual work and men with man-buns) can't get it off at all without compressing the pressure on the coupling.

R..
 
My concern was the proper procedure to decouple the hose, if a stuck inflator event did occur. The discussion on the other diver's death was a catalyst for asking the question. The common response for a stuck inflator is "uncouple the hose". That's great advice, but how to do so would be much more useful.
.

You will need to practice this, but it works 100% of the time.

Your left hand needs to hold the inflator. In 99% of cases the inflator does not stick wide open, it will "leak" as opposed to "free flow". Even when frozen open due to cold water. A "leak" is technically a free flow but it happens in slow motion.

So most times you will not need to go vertical. However, if you believe you are being caused to ascend then you need to

a) go vertical
b) hold the inflator above your head in your left hand
c) press the "vent" button

This will stop the ascent. However, it will not stop the free flow.

In order to uncouple the hose from that position you need to

a) wrap your 2nd, 3rd and 4th fingers around the LP hose (2nd finger being the FU finger, the third is the ring finger and 4th is the pink).
b) PUSH HARD in the direction of the coupling. Resistance comes from the left hand that is holding the valve open. Push them toward each other
c) use the index finger and the thumb to pull back the sleeve on the LP hose at the coupling. Inside the hose there is still 10bar of pressure and as soon as you pull the sleeve back it will pop off.

All of this, with a little practice, can be done in a few seconds.

I'm surprised you didn't learn this in your OW course. What did your instructor tell you?

R..
 
Hi rainpilot and Diver0001

Thanks for the feedback.

Diver0001: We did not cover stuck inflators in OW, at least to my memory That was 21 years ago, though. I still have my PADI OW manual from 1996, and there is no mention of managing a stuck inflator. The manual does mention emergency buoyant ascents, but that is as close at it comes..
 
Hi rainpilot and Diver0001

Thanks for the feedback.

Diver0001: We did not cover stuck inflators in OW, at least to my memory That was 21 years ago, though. I still have my PADI OW manual from 1996, and there is no mention of managing a stuck inflator. The manual does mention emergency buoyant ascents, but that is as close at it comes..

I have no memory of this skill from my own OW course in 1984 either. I think even since 1996 that attitudes and knowledge levels have changed about a number of things.

Your profile seems to indicate that you are a new diver. Getting back into the game?

R..
 
https://www.shearwater.com/products/peregrine/

Back
Top Bottom