Small incident

[KMD]

Hi guys,

I'm a new diver and I thought I would relate a small incident that I had experienced and some of the thoughts that I took from it.

This happened on the first dive of the day during my AOW certification. We both did a giant stride into the water and after a brief moment to get things together started to descend. At about 4 to 5 meters depth, my instructor was slightly ahead of me and something caught my eye. As I focused more fully on her, I saw that her tank had started slipping through the BCD strap and she had instinctively reached back to grab it before it slipped fully through.

I swam over, put my hands on the tank to stabilize it and then made eye contact with her and signaled OK that I saw the problem and was working on it. A quick lift and a tightening of the strap and a final wiggle of the tank to make sure it was secure and a another signal/response OK that the problem was fixed and we were off on the rest of our dive.


The lessons/thoughts about this that I took from it are:

1) I could have missed the looseness of the strap during the surface buddy check. If so that was a failure on my part.
2) During the problem solving I became very tunnel visioned. Except in a general way, I would not be able to tell you, who was around me, were we sinking or were we rising, what was my air supply situation. I think an awareness of these things during times such as these is important. I can’t help my buddy if I get myself in trouble.
3) Even a small incident such as this, uses up a noticeable amount of air. My total dive time was reduced by 10 minutes from normal.
4) What caught my eye that there was a problem wasn’t the instructor signaling me, or me seeing the tank slip off, it was that I had gotten used seeing my instructor use easy deliberate movements, suddenly saw her move more "urgently". Not panicked, but a more rapid than normal movement. In the future, I will try to use this as an indicator that someone may be having problems.

Kevin

 

[DennisW]

You did a great job with this situation. After you are more comfortable diving, the awareness around you while dealing with situations will be there. You must have a good instructor, because most of the new divers I see making their open water dives shouldn't be there yet.

 

[Marek K]

1) I could have missed the looseness of the strap during the surface buddy check. If so that was a failure on my part.

As far as that particular point is concerned, that may not be so.

Tank straps -- at least many of them -- have a tendency to loosen up when they get wet, enough to cause a problem like this. This may vary with tank-strap material; and it may only be true with a new or almost-new strap.

If that was the case, then the strap could very well have been completely tight prior to the dive.

My BC has two straps, which probably helps. But I always make it a habit to briefly dunk my BC into water before attaching it to the tank. Also, I loop the webbing loop that's at the top of the backpack under the tank valve, before attaching the regulator. That way, if the tank does slip out for some reason, the regulator at least won't be pulled from my mouth...

--Marek

 

[TSandM]

Just to add something here . . . I got a little lesson BEFORE I got in the water yesterday. I had tightened the strap on my tank well, but it was crooked across the tank. Bob pointed out to me that if I got a little loosening from getting in the water, that would allow the strap to slide until it was straight, which would create more slack and pose a risk of losing the tank. Hadn't thought about that before.

With regards to the tunnel vision, I think that's partially a side effect of inexperience. I know that, especially in the beginning, I was so overwhelmed by breathing and trying to manage my buoyancy that I didn't have enough attention for ANYTHING else. Each dive, that gets better.

 

[sbesana]

I had tightened the strap on my tank well, but it was crooked across the tank.

Same thing here.

I've learned to double check that the strap is perpendicular to the tank. This very problem seems to happen more often than expected...

 

[wreckchick]

There is a way you can tell if a tank is going to slip....

If you look at someone standing up in their gear, the cam band should be straight across the tank, if it's crooked, the tank will slip. Another thing I do before I let anyone get in the water is grab the buckle and jiggle it. If it wiggles, the tank will slip. I honestly haven't seen any difference in the premoistened bcs and those assembled dry. I do see a LOT of improperly threaded cam bands. If you aren't sure if yours is done correctly, have someone check it and DON'T completely undo the band(s) between dives.

YMMV

Rachel

 

[KMD]

I honestly think it was a combination of the band not being perfectly perpendicular to the tank and it stretching when wet.

Me personally in the limited amount of experience I had, I found it dificult to properly secure the BCD to the tank when it was in its rack on the dive boat. I got in the habit of taking it out of the rack, securing the BCD to it and then placing it back.

...of course this is much easier to do when in the harbour and not out in open waters.

Kevin

 

[dbulmer]

KMD,
Well done, you were aware of what was happening and stopped something small from turning into something big. You were also close enough to see and do something about it.

You were ready to help and did - buddy checks are important but mistakes can be made by both buddies and you both returned safely to learn from it.

 

[ScubaSarus]

You did great there. Merek is right, bands appear tight on the surface and loosen when wet and sometimes not until the end of the dive. Job well done. And I'll take note of the band angle in the future for I didn't know that clue to a loose strap. I have 2 bands on my BC for redundancy after my take came loose the first time in a freezing dive in the winter.

 

[discrepancy]

What caught my eye was that I ... suddenly saw her move more "urgently".

Good job keeping an eye on your fellow divers. Maybe a sharp-eyed buddy will help you out of a jam one day.

Tanks slipping is fairly common and generally no big drama, especially if you put the loop of your BC over the tank valve before fitting the first stage.

But, I saw one guy stomping out of rough surf carrying his tank (not recommended procedure), and I saw another guy sitting on the bottom of the ocean with his BC off on the sand in front of him so he could tighten his tank strap properly. Better not to have it slip in the first place.