Failed BCD pressure relief valve

[MattJ]

Good question.

You swim to the surface with the weight you intend to drop (in your case, 30 pounds IIRC) because with the weight, you'll have a swimming, controlled ascent. If you drop 30 pounds of weight, I imagine your ascent will be uncontrolled.

If you couldn't swim up with the weight, you could ascend, hand over hand, up the ascent line. But that goes back to the previously stated issue of whether or not you were overweighted.

 

[cerich]

Diving and thinking is good, you did fine and will be, I'm sure, a really good diver.

I agree with the above, may I also add that you must have been horribly overweighted to not be able to swim up....

BCD OPV failures are exceptionally rare, did you find out what happened (from what you describe it sounds like the spring broke which would be unusual to say the least)

 

[mikeyjoe]

First - major kudos for not panicking!

Second - excellent follow up question.

It is usually better to swim up with the weight, if you can, before ditching it.

If you ditch weight at depth, you could cause such a big buoyancy change as to cause an uncontrollable ascent - possible DCS hit - lots of bubbles, ride in the chamber, possible death - not cool......

You did awesome - congrats. 95% of new divers would have gone into a state of intense panic.......

Edit - 30 lbs seems like an incredible amount of weight for just a wetsuit - I wear 29lbs with a 7mm neoprene drysuit.......

 

[TSandM]

Where you drop weights depends on a number of things. For the most part, it shouldn't be necessary to drop weights at depth. The only exception to this would be a complete BC failure (torn open) at significant depth (greater than 60 feet) while wearing a heavy wetsuit. In that case, you could be so negative you can't swim yourself up, and would have to ditch weight. Of course, as you ascend, that neoprene you're wearing expands and becomes more buoyant, so if you have ditched weight at depth, there is a significant likelihood that you will have problems controlling your ascent in the shallows, which is never good.

I'm really happy to hear that you thought stuff through, but another thing to remember is that the dump valve is ONE hole in the BC. There's a lot of BC, and some of it will still hold air. All you have to do is get in a position where the hole in the BC is below as much of the bladder as you can manage. In your case, if the dump was at the top of the BC, you might have to go into somewhat of a head down position, or put that shoulder down, and swim forward that way, but you might be able to stay off the bottom and retain good visibility by doing that.

But the most important thing is that you didn't lose your cool. Thinking a problem through and examining the possibilities is the mark of someone who is going to make a very fine diver, IMHO.

 

[Gombessa]

BCD OPV failures are exceptionally rare, did you find out what happened (from what you describe it sounds like the spring broke which would be unusual to say the least)

Well, I wouldn't dismiss it outright. Watch the last 30 seconds of this, which happened to us just two weeks ago:



Luckily, the diver who lost his OPV was diving a balanced rig - he could stay at the surface with a failed wing (in this case without ditching any ballast) and had a drysuit for redundant buoyancy. It was really a non-issue, even during the 10-minute surface kick back to shore (which IMO is the best result you can ask for in this kind of scenario).

 

[AbyssalPlains]

First off, Congratulations on handling a potentially scary situation rationally. Were you at Pleasant? Just curious. As for dropping weights, there should never be necessity to drop them, unless your BC does not hold any air and you are too far from the boat or shore. If you can't stay afloat without dropping weights by just kicking your fins, for a short amount of time, even with an empty/defective BC, you are overweighted. Here is why: You should have enough weight to offset the positive buoyancy of your uncompressed wetsuit at the surface and an empty tank at the end of a dive, but barely. Ideally, you should be able to keep your head out of the water with an empty BC and a full lung of air. On descent, if you don't have to fully exhale and not take another breath until you have sunk a foot or two, you are carrying too much weight. That said, I know that instructors routinely overweight their students. Justfor comparison: When I dive in the lake with a 7mm suit, I carry about 10 pounds, which is a third (!) of the weight that they put on you.

 

[cerich]

Well, I wouldn't dismiss it outright. Watch the last 30 seconds of this, which happened to us just two weeks ago:



.

I believe it happened, just curious of the fault. About 10 years ago there was a batch of halcyon wings with OPV's that got stuck in the open position, the hard plastic circle the string is attached to was getting hung up and staying open. It is rare.

 

[Hallmac]

Personally, I would have taken the unit off, turned it upside down or what ever angle I needed to put the malfunctioning dump towards the bottom, and added some air. I would have then bear hugged it and swam a slow ascent towards my exit point.

Good job with your reaction to the problem.

 

[AZFinDiver]

I didn't really think about how the wetsuit affects buoyancy. I was wearing a 7mm wetsuit in about 54 degrees Fahrenheit fresh water. Yes I was at Lake Pleasant, I found it more fun than I expected (which was a murky old lake). The BC valve that failed was the top one over my right shoulder. I never did find out what happened to the valve. For my weights, I had 20lbs in the removable pouches, 4lbs in my front pockets and 6lbs in the back pockets. So, there would be 6lbs I couldn't easily remove.

My experience was at the surface there was no way I could keep my head above water without air in my BCD. Even at 50ft I had considerable air in my BCD to get neutrally buoyant. I also noticed when I was swimming, letting out a breath I would sink pretty fast and changes in depth changed my buoyancy pretty quick.

I am doing the Advanced Open Water this weekend at the same lake so hopefully it will be uneventful. Although, I would rather learn to deal with it there than on my first "out of school" dive in Panama City, FL this June. Anybody have recommendations for good first dives in Panama City, FL?

As I said, I'm pretty new and there is a lot to think about and a lot to learn. I really appreciate the feedback, I think it makes better divers.

 

[AZFinDiver]

Personally, I would have taken the unit off, turned it upside down or what ever angle I needed to put the malfunctioning dump towards the bottom, and added some air. I would have then bear hugged it and swam a slow ascent towards my exit point.

Good job with your reaction to the problem.

I like this suggestion. Are there any pitfalls in doing something like this?