Bc Over-inflation Due To Equalization Trouble.

[archer1960]

This isn't much of an incident as such things go, but it had the potential to cause trouble with lung over-expansion if things weren't handled, so I thought it deserved posting.

I'm a pretty new diver, with ~30 dives under my belt. Yesterday was my first dive of the season, and my first one in about 4 months. At one point my buddy and I had come to the surface to do a long-ish swim to join another buddy pair a ways away. When we started to descend, I was having a little trouble equalizing, as is fairly common for me on the later descents of multiple-descent dives. Not a lot and not painful, but I could feel the pressure in my ears when I got to the bottom at ~19 ft. So I tapped my inflator to put a puff of air in my BC to get neutral after the descent. But with the pressure in my ears, I couldn't hear the inflator go. Since I was wearing bulky gloves, I just assumed I had missed the button, so I hit it again a couple more times, including one long one. However, I had actually hit the button all 3 times, so I started going up in a hurry. I turned head down and started finning hard while reaching for my butt dump, which took a while to find since I was a bit out of practice. I bounced up to probably 7 ft in a few seconds before I started back down again. This time I was more careful, and made sure my ears were fully cleared before tapping the inflator again, and I reminded myself to wait to see the effect before doing another puff. I still overshot by a small amount a couple of times before getting it zeroed in, but nothing that threatened to shoot me to the surface again.

Just a reminder to be sure to take it easy and slow down after a long layoff!

 

[Jax]

Excellent lesson!

 

[Altamira]

I suspect most of us have done that at one point or another in diving. If I have a problem equalizing on the descent, I usually have to ascend 5-10 feet to get the problem cleared, and plan on possibly having to dump air rather than add air. If I had gotten to the bottom at 19' as you did, and was a bit negatively buoyant but still had trouble equalizing, I would not worry about being negatively buoyant at that point, but fin upward the 5-10 feet or so, to help equalize, not adding any air to my bcd. Swimming up my weights has never given me a problem, but adding air to the bcd when you may have to ascend to deal with an issue could cause you al lot of trouble.

 

[archer1960]

I suspect most of us have done that at one point or another in diving. If I have a problem equalizing on the descent, I usually have to ascend 5-10 feet to get the problem cleared, and plan on possibly having to dump air rather than add air. If I had gotten to the bottom at 19' as you did, and was a bit negatively buoyant but still had trouble equalizing, I would not worry about being negatively buoyant at that point, but fin upward the 5-10 feet or so, to help equalize, not adding any air to my bcd. Swimming up my weights has never given me a problem, but adding air to the bcd when you may have to ascend to deal with an issue could cause you al lot of trouble.

Good point; thanks for the comments.

 

[Neilwood]

I had a similar issue with an inflater however it was not related to equalization.

Mine was due to changing between a traditional jacket BC to a Scubapro BP&W with a different style of power inflater. Instead of having the two buttons at an angle, they were placed side by side.

instead of


On a couple of occasions where I was rising gently, I pressed the button (by feel) only to find that I started to rise more rapidly instead of arresting or slowing my ascent.

Lesson learned - if buying new kit especially that which works in a slightly different way, get used to the feel of it before getting in the water.

 

[archer1960]

I had a similar issue with an inflater however it was not related to equalization.

Mine was due to changing between a traditional jacket BC to a Scubapro BP&W with a different style of power inflater. Instead of having the two buttons at an angle, they were placed side by side.

instead of View attachment 373649


On a couple of occasions where I was rising gently, I pressed the button (by feel) only to find that I started to rise more rapidly instead of arresting or slowing my ascent.

Lesson learned - if buying new kit especially that which works in a slightly different way, get used to the feel of it before getting in the water.

I had that kind issue at first with mine as well. The inflate button is big, and is really easy to accidentally press at the same time as I'm pressing the deflate button, if I have heavy gloves on (which is often, here in New England).