Failed first stage

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I believe I did - probably not completely head down feet up vertical, but I suspect my mask was well below my fins due to taking pictures of that flounder on the bottom.
I watched it happen once. Ladies tank went from 1600 to zero in a breath at 130'. I've been around a fisherman who had it happen while he was in deco at 140". He can kind of walk now but he spent a year or two in a wheelchair. We have rented tanks from DP to shore dive several times but won't again. I'll pay them the money but bring our own tanks.
 
Glad you are OK. As mentioned, kudos to your wife/buddy for remaining level headed and getting you to the surface safely.

Easy to say after the fact but maybe a good time to invest into more equipment.
 
Did you go head down just before it happened. I know of two Mexico incidents, one that I witnessed of a diver going head down and losing air. The cause, debris in the tank and likely no dip tube.

In February I had a person that should know tell me that Dive Paradise was doing no maintenance on their equipment. He said failures were common.



From the original post it seems another tank was tried without success, as well as a different tank on the original tank. Doesn't seem to be a dip tube issue unless it clogged the filter completely.

[ He then tried it on another tank, again with the same result. Next he tried a different reg on the tank I had been using, and confirmed that it still had air - the gauge still showing about 1000 PSI.]
 
From the original post it seems another tank was tried without success, as well as a different tank on the original tank. Doesn't seem to be a dip tube issue unless it clogged the filter completely.

[ He then tried it on another tank, again with the same result. Next he tried a different reg on the tank I had been using, and confirmed that it still had air - the gauge still showing about 1000 PSI.]
Correct. My error.
 
Correct. My error.

BRT, still of interest to note the dip tube issue.

OK, you out there that know these types of things, what causes a first stage to fail closed?

I thought firsts were all built to fail open?
 
Personally know a diver this happened to at Coz. They get flooded by divers, and seldom VIP'ed I think.
 
I have seen a well maintained 1st stage reg fail closed. If memory serves it was a deco reg and the diver simply switched over to back gas. Examination showed that the high pressure seat had come loose from the metal surround and blocked the air passage. It can happen to anyone at any time.
 
I have seen a well maintained 1st stage reg fail closed. If memory serves it was a deco reg and the diver simply switched over to back gas. Examination showed that the high pressure seat had come loose from the metal surround and blocked the air passage. It can happen to anyone at any time.
I only know anything about older Sherwoods but I don't really understand how this can happen. Maybe a broken spring?
 
I only know anything about older Sherwoods but I don't really understand how this can happen. Maybe a broken spring?
HP seats are basically a tiny chunk of nylon glued into a little brass cup. If the glue comes undone they tend to stay put from pressure BUT... If they come loose they will smush into a downstream hole leading to the LP hose
 
I also have seen a similar problem due to debris (mostly rust) clogging the metal filter of the reg (not the dip pipe). The interesting point is that when this happens, the SPG still indicates the true pressure in the tank, as the minimal air passage remained is enough for pressurizing the SPG. But when you inhale, then the indicated pressure drops, and then comes up again slowly...
A freshly replaced filter on the reg could help, but just partially. So when this occur you still have problems using your own reg (as it happened to me).
Here in Italy all tanks have two valves, and when I was trained the rule was to always mount two independent regs, with two first stages. This can make a case like yours not so dangerous, although the secondary reg usually does not have any SPG, nor the hose for inflating the BCD; so a failure of the main first stage is still a severe problem.
But there is little else you can do, as the tank is almost inevitably rented when you fly to a remote tropical place.
Now that the standard here is to use DIN regs, which are much safer, most people (me included) is not using anymore two independent first stages.
So you can just hope there is not too much debris inside your rented tank.
 
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