Exploding scuba tank kills one - Florida

[DMDavid]

An update from the local PD says the 23 year old diver had just returned from Iraq.
The rest of the article is speculation from a local dive shop manager.

http://www2.tbo.com/news/breaking-n...man-dies-after-scuba-tank-explodes-ar-256967/

The updated article does contain the name of the diver.


FB-Florida Scuba Diver

 

[JahJahwarrior]

I could swear I've seen atleast one, and maybe more, photos of aluminum cylinders that split into more than one piece. Compressed gas has a ton of energy stored up...you should have seen me wince when a customer showed up at the dive shop and started throwing 6351 80's out of the bed of his pickup into the ground by the fill station!

Certainly, this does not have to be a bomb, or an oxygen tank.

Interesting, how a dive shop owner doesn't seem to understand burst disks or that whole PV=nRT thing... besides, even in Florida, the heat isn't that extreme at 6:50am inside of an apartment.

 

[ggunn]

Wouldn't it have to be Oxygen to explode like that...??

Oxygen is no more or less explosive when a tank ruptures than any other gas. Chemical explosions involving oxygen bottles can occur when combustible oil or grease contaminate a cylinder, but that would have happened during the fill process, not during transport.

 

[DandyDon]

Oxygen is no more or less explosive when a tank ruptures than any other gas. Chemical explosions involving oxygen bottles can occur when combustible oil or grease contaminate a cylinder, but that would have happened during the fill process, not during transport.

After this thread and the youtube video http://www.scubaboard.com/forums/accidents-incidents/365310-o2-tank-explosion.html I'm giving O2 bottles a lot more respect.

 

[ggunn]

After this thread and the youtube video http://www.scubaboard.com/forums/accidents-incidents/365310-o2-tank-explosion.html I'm giving O2 bottles a lot more respect.

I can't watch youtube videos on my old Mac any more, but I did work as a chemist in a specialty gas lab for a few years. Compressed O2 cylinders are no more (or less) dangerous to handle than those of any other gas. To fill, yes, because even a little bit of combustible grease or oil contamination can cause a cylinder to explode when the pressure gets high enough for it to autoignite. SOP in our lab was that any O2 cylinder returned to the lab with less than 100 PSI was converted to some other service because of the possibility that it could be contaminated.

 

[DandyDon]

A local thrift store had a few medical O2 tanks for sell. I convinced the manager to contact local police to assist in safely disposing them. I had considered playing with them until I saw the youtube vid.

 

[Redfishingirl]

I could swear I've seen atleast one, and maybe more, photos of aluminum cylinders that split into more than one piece. Compressed gas has a ton of energy stored up...you should have seen me wince when a customer showed up at the dive shop and started throwing 6351 80's out of the bed of his pickup into the ground by the fill station!

Certainly, this does not have to be a bomb, or an oxygen tank.

Interesting, how a dive shop owner doesn't seem to understand burst disks or that whole PV=nRT thing... besides, even in Florida, the heat isn't that extreme at 6:50am inside of an apartment.

Perhaps the difference in temp from inside to outside? Some people really crank the AC down in the summer. Don't know if a 15 degree difference would do it?

 

[Chugwhump]

CRAP!


Chug
Watching, concerned, sad.

 

[DandyDon]

Perhaps the difference in temp from inside to outside? Some people really crank the AC down in the summer. Don't know if a 15 degree difference would do it?

An AL80 weights 31-35# plus valve, altho I swear they feel twice that heavy carrying across a parking lot, so that's a lot of metal to absorb temperature changes. Even if a tank were to overheat after sitting in a hot car or something, the burst disk is supposed to give way.

 

[JahJahwarrior]

Perhaps the difference in temp from inside to outside? Some people really crank the AC down in the summer. Don't know if a 15 degree difference would do it?

The tank would have to be very overfilled for 15 degrees to make a difference. Also, the burst disk would have to malfunction. To put this in perspective, consider the gas formula I posted earlier. Run the numbers and calculate the pressure difference yourself. Hint: v, n, and r are equal. P will change in relation to t, and remember that t is in absolute.

I keep my tanks filled to the proper fill pressure in a Florida garage, and often have 80's and 40's with nx and 100% o2 in a car parked in the sun. Not to say that my anecdotal experience speaks to every situation, but I get tired of dive shops that don't understand how to fill tanks. The rated fill pressure is a pressure and temperature combination. Tanks can handle higher pressures within a safe range. Sad that dive shop owners don't understand these basic concepts.

Don't get me started on the overly simplistic determination by the dive shop owner of what tanks are 6351 alloy.

I will be very interested to see more details. If he was going to use it, odds are it was filled (also judging by the fact that it exploded with great force...an empty tank wouldn't have nearly as much energy) if it was filled then it may or may not have been filled recently. So it may or may not have been in hydro and VIP. So it's hard to say what might have gone unnoticed. I never try to hide my aversion to 6351 alloy. I'll be interested to find out what alloy this was but don't want to needlessly speculate.