When I saw this image, I was immediately reminded of several images as seen in this YouTube video:
The video has about 20 seconds of black screen, in the beginning, as the incident is narrated. (Obviously) the causes are different, but some similarities may be drawn. Perhaps SLC was a cause? I will re-think many of the common practices we use with our deco bottles.
All the best, James
I would like to thank you for posting that video. I have found this accident extremely troubling, first because of the terrible nature of the event and second because I have had difficulty understanding exactly what happen, and how anyone could have done something differently to prevent the event.
The video you posted, for all practical purposes is, as best I can tell an almost identical event. The only difference being what cause the initial leak.
Why would a O2 tank explode from a valve leak? Well, if you look for video's of people shooting tanks, compressed air tanks just shoot around, while even low pressure O2 tanks explode. Obviously O2 is not explosive, and is not a fuel, and yet if you shoot one, you get an explosion. I believe it is because even tiny amounts of metal, dust or anything that can act as fuel, will react so quickly that the expanding gas is faster that the container (even a container with a hole now in it). It expands to the point where the tank blows apart, and now there is lots of fuel to continue the flash.
But what provided the energy to ignite the fuel? O2 is a much thicker gas than air, and going thru the tiny opening must have heated some of the tiny particles. In the case of the video, just breaking the seal on the valve provided enough material to explode the tank. I believe the tank dropping on the value would have actually released a lot more fuel.
I found that there have been several reported cases of Large O2 tanks blowing up and/or igniting inside the regulator from falling over and then just opening the valve at a later date. It is the reason for the OSHA requirement to have the tanks secured. Any fall off from the inside of the tank can be very dangerous.
I had no idea just how dangerous compressed O2 can be. IF I had one fall off a table onto the floor, my reaction would have been to reach down and pick it up. If I had a tank get knocked around on a dive trip, I would not have thought to drain the tank away from anyone and have it inspected.
I find it very sad to have learned this from such an event.