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an aluminum scuba tank is filled to around 3k psi; they're quite energetic if they explode


This guy died and damaged cars 100ft away from the center:


Now, the article says 100psi not 3k, but you'd still probably rather not be near it.

100 atmospheres is approx 1500 psi.

I inflate bike tyres to 110 and its nothing tbh, 1500psi is a different kettle of fish.

Wow. In the first example, it seems those weren't scuba tanks, but rather pressurized air containers that are used to fill the real scuba tanks - they are quite a bit larger. Never seen those before.

Actually the article says that people are also killed by exploding truck tires which are around 100 psi and further states that SCUBA tanks are pressurized at up to 3000 psi.

Isn't the pressure only part of the danger? In my non-scientific experience, it seems that the speed of failure is the important part. i.e a truck tire with a nail in it does no harm, but a 15-ply semi tire at 100psi having a catastrophic failure is a much different animal. All about the speed of release.

My own personal story: some friends and I filled a 5 gallon bottle with a bit of isopropyl alcohol, shook it up, and lit the opening to make a "rocket flame". We had seen this done in class, and it went fine. BUT...we wanted to do it again. we had no more alcohol, so we used Acetone instead, but it wouldn't light. There wasn't enough air in the bottle, since we had just burned out the oxygen. Because we were 16, and lacking much foresight, we decided "why just put air in the bottle, when we could use pure oxygen from a welding tank?". We did that. The ensuing incandescent explosion lit up briefly like a lightbulb and then ruptured the bottle into about 100 pieces. the major one landed 2-3 seconds later, about 200 feet away.

Even though that was moronic, I pride myself for having worn welding gloves, a face shield, ear plugs, and used a 12 foot handle with a match on the end. The detonation left me feeling shaky and jittery for about 6 hours.

My point is, speed of failure is important.

That story belongs over on the "Under Pressure" thread! - https://news.ycombinator.com/item?id=9444675

I think it is?

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