Runaway BC

[Erbun]

While browsing I just saw a post on this topic and thought I should share my experience as you never know who may read what and benefit from it.

I was doing a dive this weekend, fairly shallow, thank goodness. Towards the end of the dive my buddy signaled to follow. Now I want to add here that I think I was slightly overweighted. At the bottom it took a couple of good squirts of air to trim off. I will call this mistake number 1. My buddy was beneath me as he signaled and I started to follow. I went to spin over to follow and when I raised a couple of feet I started to raise. Here is mistake number 2 and 3. Mistake number 2, in my opinion anyway, was to go head down to swim after without dropping air out of my BC. Mistake number 3 was not knowing my rental gear as well as I should have. As I said I am super newbie. While inverted trying to swim down, I continued to go up. I tried to dump air as fast as possible, however I was unaware of the dump at the bottom of the BC, in this position the top, where you want air to come out of. That being said Had I remained calm, Mistake number 4, I would have realized I was trying to dump air out of what would be the bottom of the BC, gone into a feet down position, and been able to dump air.

So as you can imagine, I wound up on the surface. I have to major things I am thankful for here. Only being at 25 ft, and CESA training. (Although instead of a hmmmmm, it was probably more of a AHHHHHHHH). This was singularly the scariest moment of my life, yet I am thankful for it because I am blessed to have this happen at a time and depth where I am ok, and I can assure, I will not forget the lessons listed above that I am taking away with me.. To say them once more I will list them here.

1: Work on you weighting. Proper weighting prevents improper BC control.
2 + 3: Pay attention to where your air dumps are located at and know your gear so you are aware of this before a dive.
4: Remain calm. Panicking leads to missing and not remembering things that you normally would.

So in all, I am posting this in hope that someone will learn from my mistakes. I am a brand spanking new born when it comes to diving, but already it is quickly becoming the love of my life (aside from the girlfriend of course), and I would hate to see someone who may become a great dive buddy one day get turned away from this sport from not knowing how to prevent this or worse, get injured.

 

[dumpsterDiver]

Your expereince is much more common than you suppose. what is unusual, I think, is that this was the scariest moment in your life.

 

[Erbun]

During the course of the ascent not as much. I did "panic" but for the most part realized I was going up, I should be safe depth wise, and remembered CESA. The reason it was the scariest moment of my life is this is literally one of my first dives, and the first dive of the day was at 60 ft, where results could have possible been much worse. Right after it happened it was definitely an eye opener, and I spent probably a good 2 minutes waiting for my head to explode or something. Like I said super newbie But I decided to take what I can out of it, and insure that it doesn't happen again.

 

[Puffer Fish]

You are not the first and will not be the last. Knowing your rental gear is important, but understanding a BC is even more important.

I have no idea how often I've seen someone try to dump air when inverted, with the regular dump...it for sure is hundreds, but may be thousands.

Glad you learned from that.. and thanks for posting.

 

[RubberDucky]

Great post Erbun, thanks for sharing your experience. Not only did you recall your training by keeping your airway open as you took the elevator ride to the surface, but you'll clearly improve as a diver from reflecting on the incident and finding a few holes in your game. You're right on target about the importance of not only knowing where your dump valves are, but the importance of knowing what position to be in for them to be effective.

I'd also like to point out one additional thing that you can add to your toolbox. Let's say you're at depth (25 ft, 50 ft, whatever) and need to put a little air into your BC. While doing so, the inflator button gets stuck. What do you do? Your BC is rapidly filling up with air, and if you don't react immediately, up you go.

Since you're focusing on knowledge of your gear, this may also be a good time to practice disconnecting the low pressure inflator hose on your BC. Just please remember to reconnect it so you can inflate your BC once you're at the surface. Or, you can always orally inflate it, which is another skill that never hurts to practice routinely.

Finally, welcome to ScubaBoard!

 

[Erbun]

@RubberDucky - Great point! I honestly had never thought of that before, and the fact that you mention it I['m guessing means you've ever had it happen or seen it happen so definitely good knowledge to think on. Thanks!

 

[dumpsterDiver]

@RubberDucky - Great point! I honestly had never thought of that before, and the fact that you mention it I['m guessing means you've ever had it happen or seen it happen so definitely good knowledge to think on. Thanks!

If your instructor did not make a big deal out of the possibility that the BC inflator may one day stick in the on/inflate position, then your instructor SUCKED. No other way to put it and it is not your fault. A stuck inflator is probably the most common scuba failure other than a free flow.

If you ever get into an uncontrolled, buoyant ascent, you need to roll onto your back flair out like a sky diver and dump air from the inflator and simulateneously try to disconnect the inflator hose (if the cause of the problem is a freeflowing/inflating inflator).

I get so pissed when I hear that new divers have not been taught this stuff.

 

[TSandM]

I do a lot of diving with new divers. Some of them are in rented or borrowed equipment, but some of them are in their own, newly purchased stuff. Without exception, not a single one of them has had any idea where any of the dumps from their BC are, other than the inflator and whether or not it functions as a pull dump as well. They weren't taught to look for the other dumps, and no one has gone over how to decide which site is best to use to dump gas, depending on posture. Certainly, no one said a single word about this during MY open water class.

One of the most important things you can know is where you can vent gas. I would highly recommend that you have a good look over any gear you rent, and discuss the dumps with the shop from which you are renting. AND I would strongly suggest that, during the buddy check, you AND your buddy go over all the venting options each of you has, so that you reinforce for yourself what your options are, and so that you can most effectively aid your buddy, should he have a buoyancy "oops".

 

[RubberDucky]

@RubberDucky - Great point! I honestly had never thought of that before, and the fact that you mention it I['m guessing means you've ever had it happen or seen it happen so definitely good knowledge to think on. Thanks!

Good guess! It happened on one of my OW checkout dives. However, I lucked out because it took place when I was already on the surface. The button was stuck for perhaps 10 seconds or so and I was beginning to wonder if the BC was going to go *BOOM*.

However, I think that I didn't really consider the potential for disaster of a stuck inflator hose until I read something in the Accidents & Incidents section on these forums, though I don't remember what. The next time I was in Cozumel I asked a number of very experienced divers what they would do in that situation while at depth. In retrospect, I'm a little surprised at the varied responses I received.

One of my instructors hit the nail on the head about disconnecting the LP hose first and that's what I practiced on my next dive. I found it a lot easier to disconnect than to get it connected again. On another dive I realized how unimportant that hose really is. I swam up to the DM and pointed at his LP hose to show him that it was disconnected. He then grabbed it and banged on his tank with the metal end of it.

 

[aquaregia]

Mistake number 2, in my opinion anyway, was to go head down to swim after without dropping air out of my BC.

Wait, you're saying that you should have dumped air from your BC to descend further from depth?