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How much time do I have with a stuck inflator

Discussion in 'New Divers and Those Considering Diving' started by haumana ronin, May 1, 2011.

  1. haumana ronin

    haumana ronin Regular of the Pub

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    If my BCD inflator were to get stuck open, how much time to I have to disconnect/vent before it could lead to injury?

    I know there are a few different factors such as depth, starting position, and how open the inflator got stuck, so what are the different scenarios that you have actually seen?:shocked2: I wouldn't think that feet down at the safety stop is a good place to be when your inflator decides open fully. Has anyone been able to stop from this depth? What is the shallowest that anyone has stopped a runaway BC incident? Has anyone had to go to their knife?:eyebrow: Would you even have time to?

    What is your ascent rate with a BC fully inflating? How much does flaring reduce your ascent speed? Obviously, I don't want to test this on myself just for the heck of it.:no:

    I think starting at a good depth and kicking down with a small or medium lift BC could give you some time to disconnect/vent, although, kicking down does put the BC inlet near the lowest point, so I am not sure what is best.:confused:

    Is there a way to practice this besides just disconnecting and reconnecting at depth? :idk: Seems like this might actually lead to the aforementioned ascent, but I don't know. Would quick piking practice help at all?

    I have seen the other thread with the Hat, so don't post that.:tongue2: And yes, proper BC maintenance and not holding your breath on the way up are two important things too...

    :zen:
     
  2. Brendon

    Brendon Barracuda

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    I would not recommend diving with a bcd as you have described. However if it happened on a dive I would disconnect it as soon as you notice it and dump air until you are neutral. At your skill level, abort the dive. How long it would take to become dangerous or lead to injury is irrelevant. There are to many variables to consider, giving out some kind of time frame before an injury would result is not worth the time spent figuring it out.
     
  3. evad

    evad Solo Diver

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  4. fisheater

    fisheater Divemaster Candidate

    # of Dives: 200 - 499
    Location: Sebastopol, CA
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    Inflators are designed to dump faster than they inflate. So, if you dump while futzing with the hose, you have as much time as you have air. :)


    Sent from my iPhone using Tapatalk
     
  5. Jax

    Jax Responsibility Dodger ScubaBoard Supporter

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    Practice the sequence without looking - Inflator sticks, hit exhaust button, disconnect hose. 1-2-3 Practice until it comes flawlessly without fumbling.
     
  6. spectrum

    spectrum Dive Bum Wannabe ScubaBoard Supporter

    # of Dives: 500 - 999
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    The dump valves on most BCs are designed to vent faster than the inflater can fill. That means that if you notice the valve is stuck the first thing you can do is dump air to control the situation for the instant.

    Once you are into the situation disconnect the inflater hose. Many BC have a tug dump valve integral to the inflater assembly. With these you can keep tension on the inflater hose while you break the connection. Practicing this skill from time to time is your best insurance.

    In all cases you need to keep the situation under control so you are venting from the highest point.

    Pete
     
  7. g1138

    g1138 Marine Scientist

    # of Dives: 200 - 499
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    Not if you have an Air 2. Those things inflate crazy fast compared to traditional inflators. I'd call the ratio about even.


    To the OP
    Here at my school we practice BC disconnects and emergency flares for such an event. For the latter we have all our students lie 13ft on the pool bottom facing up. Once they give us an OK, DM's and instructors then mash down on the students inflator until their BC auto-dumps, then we let go. We usually have to hold them down for a few seconds before this happens. For me this is fairly easy to do.
    With an Air 2 it happens a lot quicker, I only have to hold the student for a brief second before I can let them go.

    In reality the higher you rise the harder it'll be to kick down as your BC continues to inflate and the air expands. If you have ever swam from the bottom with 10lbs of extra weight, imagine that but 3 times harder when you're trying to swim down with a full BC.

    You should be aware enough of your situation to hear or feel your BC inflating, even if you're not the one doing it. (hearing it is generally easier than feeling it IMO)

    If I hear my BC start to auto-inflate I would immediately do a Dump-Tap-Dump. That is dump my air and tap hard on the inflator button, then dump again to keep me from rising. If the inflator still auto inflates I'd then go for the inflator hose and disconnect it. You then end your dive safely. If you're comfortable orally inflating to keep neutrally buoyant then do so for your safety stop. Otherwise skip it and ascend safely to the surface, end of dive.

    On the other hand if I find myself beginning to rise before I realize I have a runaway inflator, then I'd disconnect my hose THEN dump my air, or I'd flare out if I were already rising too fast. I chose to do it this way instead of the reverse because I feel I can disconnect my BC hose quickly and I'd rather nip the problem in the bud first.

    Generally speaking, lots of our students have a hard time disconnecting their hose (not sure if it's them or the rentals, they're a bit stiffer than normal but I've never had a problem). They have an even harder time putting it back on.

    A good technique I found is to:
    1) grip underneath your inflator with your right hand, so the inflator is pointed up and your hand is wrapped around both hoses.
    2) Death grip it and invert your left hand over the top of the inflator.
    3) Push down on the collar with your left fingers and the air pressure should pop your hose off for you. (you may need to push your inflator hose up into the inflator sometimes)

    Putting it back on is trickier:
    1) First I would feed a little bit of hose off the BC hose clip (if you have one). Hold the inflator up with your left hand.
    2) Next with your right hand, move your inflator hose collar down and push it up onto the inflator, but not hard enough to send air spraying out of the hose.
    3) Finally grasp the hose below the collar and push up until you hear air leaking from the collar, at this point slide your index finger and thumb up to assist the collar in locking onto the inflator.
    4) All the while our thumb's "palm" and other three fingers should be locked around the hose and pushing up, while our left hand is pushing the inflator down onto the hose.

    Give is shot in the garage with your gloves on :D
     
  8. dumpsterDiver

    dumpsterDiver Banned

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    If an inflator started to automatically inflate, I would disconnect ASAP while dumping air. An AIR II inflator may inflate faster, but it is also about 10 times easier to disconnect in a hurry.

    For me, if an inlfator was sticking and inflating the BC (more than a trickle) I would probably complete the dive without using it. Why risk hooking it back up? Not having a power inflator on a BC should not be that big of a deal to cause you to abort the dive, unless it makes you uncomfortable.
     
    Hawkwood and Scott L like this.
  9. evad

    evad Solo Diver

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    Nothing "comes flawlessly without fumbling."
     
  10. Frosty

    Frosty Divemaster

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    Of course theres the odvious question. Why would an inflator fault?
    When you look at them they aren't exactly complicated bits of kit.
    So either you've got hooked up in weed/line/mud thats jammed it up or you are diving with a really well worn inflator.
    How would I deal with it? disconnect the inflator hose most likely then figure out what was jamming up the button.
    Happy to be shot down in flames here
     

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