Author Topic: o-ring ruptured (Read 845 times)

Steven Wong · « **on:** August 21, 2011, 06:16:38 PM »

I went to Menjangan, Bali with my usual dive buddy from Aug 4-9, 2011.
On our 2nd day, 1st dive in the morning of Aug 6 at Pos II, my buddy, DM and I decent down to 25meter.
After about 8 minutes, I heard a very loud "pomp" and followed by another one after 10 second.
Initially I thought it was "bomb fishing" as it is pretty common around Bali?
My buddy was about 15meter in front of me while our DM is 5 meter ahead of me.
My DM came rushing towards me with his secondary ready in his hand when he turned back to check on me?
The 2 loud "pomp" was because my o-ring ruptured!!!
My DM turn off my air supply and we ascend at normal rate with 3 minutes safety stop with buddy sharing air?
This was my first real experience having to use secondary under water.
Thanks to my DM, Koko.

Lesson learned; check your o-ring before every dive and have your buddy close to you at all times.
If the o-ring is not in good condition, always request for replacement?

Happy to share my experience with our dive buddies.

run · « **Reply #1 on:** August 22, 2011, 09:38:45 AM »

i had this experience before.
From that day onwards i am sensative to the sound of loud "pop" underwater

Owtaman · « **Reply #2 on:** September 12, 2011, 02:52:14 PM »

This same issue happened to my buddy before, but it seems that the air will not depleted immediately, it takes a while for the air to be fully depleted, any body care to comment how much time we have before nothing is left in the tank at say 25 meters ?

Nevertheless my immediate response was to handout my octo to my buddy which it seems may not be necessary at that moment, anybody care to comment if there was any other better options beside switching to buddy breathing immediately ?

run · « **Reply #3 on:** September 12, 2011, 04:18:25 PM »

unless your buddy suddenly grow gills, there is no other option then buddy breathing

You said

Quote from: Owtaman on September 12, 2011, 02:52:14 PM

Nevertheless my immediate response was to handout my octo to my buddy which it seems may not be necessary at that moment?

What your buddy exprience may not be a rupture.
Because when the o-ring at the tank pop, the tank for sure will loose the air in a few seconds within depth
at 20+meter. Maybe it was a free flow. Small air bubble escapes from o-ring.

oldturtle · « **Reply #4 on:** September 12, 2011, 07:43:16 PM »

hi all. is there a legal recourse of a burst o ring ? ( renting out mal function equipments ?)

run · « **Reply #5 on:** September 12, 2011, 07:55:56 PM »

hahahaha..why bothered to send for service then

oldturtle · « **Reply #6 on:** September 12, 2011, 08:26:18 PM »

? ..i am lost here run..

scubasafety · « **Reply #7 on:** September 13, 2011, 03:01:53 PM »

Rubber "O" Rings do not last forever. This is why the Operator should have a regular routine time period to change them out.

When "you" inspect your own gear before the dive you should shielding your eyes let a small blast of air out of the tank to clear any possible blockage. Then you make a visual inspection of the state of the "O" Ring and if it looks damages or worn ask to change tanks (There should be backup Tanks on the boat normally) as this is usually the most realistic situation rather than change the "O" Ring however with some Operators they will always keep new "O" Rings close at hand.

Sometimes also with some types of Tank left in the sun perhaps the Rupture Disk can blow for over pressure. This usually does not happen underwater but results in the same as a blown "O" Ring in terms of losing air faster. Depending on how the "O" Ring fails sets how fast the air will deplete.

Solution is simple. You watch your buddy and they watch you. if your "O" Ring goes do exactly as the DM here did and signal to your buddy danger sign and approach with the secondary held out to them such that it is obvious they need to take it. Then make a controlled ascent assuming it is safe to do so. If it is not safe then consider the air time is now vastly reduced and look to surface when safe whilst observing much more often the left air situation. Turning off the air will stop the noise however it creates two issues. First is that even with some burst "O" Rings you still have some primary pressure. Depending on the pressure in the tank you are very likely to both leave some secondary air pressure you might be able to return to in an absolute emergency provided the burst in not severe. Also you may well save the primary from fresh or sea water contamination because the pressure may keep out the water from the primary which then needs a full service usually after a burst "O" Ring underwater. If you switch the air off you cut the noise BUT you are likely to allow in water to the primary which virtually guaranteed that it is requiring a full service.

The DM here moved quickly and clearly has seen this before likely a few times in his career. Burst "O" Rings are of course variable in terms of how serious they can be because of the above reasons. With a buddy close by and taking the lound noise out of the equation, it is not much of a problem if your budddy switched you to their Octopus. Then see above on the ascent.

Safe Diving.

scubasafety · « **Reply #8 on:** September 13, 2011, 03:05:56 PM »

Whoops forgot. If you let it run and do not turn off the air remember that your buoyancy will change faster as the tank emties quicker. This may be a factor in controlling your ascent in due course. Also if you close the valve this may change your usual understanding of your weight situation when trying to do your safety stop as you will likely have a heavier weight still in the tank. Prepare to compensate for this as you hit the depth for safety stop.

Narco · « **Reply #9 on:** September 13, 2011, 08:36:26 PM »

I had this experience in Redang recently. Luckily it happened on land. Have got to change tanks four times. Change and burst.. change and burst.. change and burst. Upon getting onto the boat, it burst high time once again. The DM had to run to the DC to get me a new tank. The o ring seems new though. None of my buddies experience this.

Finally, i discovered, something is not right with my first stage.. hehe..

vash_h · « **Reply #10 on:** September 13, 2011, 10:18:11 PM »

i think the DM quickly turn off the air mainly to remove the noise (helps prevent people from panicking).. panic is the number 1 killer in most diving incidents..

it is easier to keep your cool underwater without the loud hissing sound..

the cost of servicing your primary is worth MUCH MORE compared to having a panicked buddy..

o-ring ruptured