3 ms·

Curious: how much damage could this have done if it actually exploded? What kind of forces are we talking about here?

x0x0 12y ago
an aluminum scuba tank is filled to around 3k psi; they're quite energetic if they explode http://www.kirotv.com/news/news/dive-shop-explosion-sends-tank-shooting-through-pa/nbPfF/ http://www.kirotv.com/news/news/dive-shop-explosion-sends-ta... This guy died and damaged cars 100ft away from the center: http://abcnews.go.com/US/scuba-tank-explosion-kills-iraq-war-veteran-russell-vanhorn/story?id=14502395 http://abcnews.go.com/US/scuba-tank-explosion-kills-iraq-war... Now, the article says 100psi not 3k, but you'd still probably rather not be near it.
- noir_lord 12y ago
  100 atmospheres is approx 1500 psi. I inflate bike tyres to 110 and its nothing tbh, 1500psi is a different kettle of fish.
- smoyer 12y ago
  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.
  - abakker 12y ago
    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.
    - smoyer 12y ago
      That story belongs over on the "Under Pressure" thread! - https://news.ycombinator.com/item?id=9444675 https://news.ycombinator.com/item?id=9444675
      - abakker 12y ago
        I think it is?
- MrBuddyCasino 12y ago
  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.
zoba 12y ago
Could have seriously damaged his hand if he was holding it. I have a permanent scar in my eyebrow from dry ice enclosed in a weak water bottle that exploded a few (4 or so?) feet from my face. There are YouTube videos of people ending up with severe hand damage from 2 liter bottles. I was cringing reading this article. I would never ever have handled one of these things, based on my experience. I think I would've put it in the fridge, left the house for at least a day, and bought a new fridge based on the damage.
Athas 12y ago
Not much. At the student revue last year, we had filled a thermos with dry ice, closed it up, and forgot about it on stage overnight. At some point during the night, it blew off the plastic valve at the top, which was ruined, but the metal flask itself was fine. The people sleeping near the stage reported a loud bang, but nothing else. Hypothesis: since the valve is only going to be propelled by the expanding gases for a relatively short time before it has cleared the flask opening, I don't even think it accelerates to that great a speed. Clarification: a thermos is more or less a best-case scenario, since the valve at the top is going to be much weaker than the flask itself. A plastic bottle is worst-case, because it is going to shatter and eject plastic splinters.

x0x0 12y ago

an aluminum scuba tank is filled to around 3k psi; they're quite energetic if they explode http://www.kirotv.com/news/news/dive-shop-explosion-sends-tank-shooting-through-pa/nbPfF/ http://www.kirotv.com/news/news/dive-shop-explosion-sends-ta... This guy died and damaged cars 100ft away from the center: http://abcnews.go.com/US/scuba-tank-explosion-kills-iraq-war-veteran-russell-vanhorn/story?id=14502395 http://abcnews.go.com/US/scuba-tank-explosion-kills-iraq-war... Now, the article says 100psi not 3k, but you'd still probably rather not be near it.

noir_lord 12y ago
100 atmospheres is approx 1500 psi. I inflate bike tyres to 110 and its nothing tbh, 1500psi is a different kettle of fish.
smoyer 12y ago
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.
- abakker 12y ago
  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.
  - smoyer 12y ago
    That story belongs over on the "Under Pressure" thread! - https://news.ycombinator.com/item?id=9444675 https://news.ycombinator.com/item?id=9444675
    - abakker 12y ago
      I think it is?
MrBuddyCasino 12y ago
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.

zoba 12y ago

Could have seriously damaged his hand if he was holding it. I have a permanent scar in my eyebrow from dry ice enclosed in a weak water bottle that exploded a few (4 or so?) feet from my face. There are YouTube videos of people ending up with severe hand damage from 2 liter bottles. I was cringing reading this article. I would never ever have handled one of these things, based on my experience. I think I would've put it in the fridge, left the house for at least a day, and bought a new fridge based on the damage.

Athas 12y ago

Not much. At the student revue last year, we had filled a thermos with dry ice, closed it up, and forgot about it on stage overnight. At some point during the night, it blew off the plastic valve at the top, which was ruined, but the metal flask itself was fine. The people sleeping near the stage reported a loud bang, but nothing else. Hypothesis: since the valve is only going to be propelled by the expanding gases for a relatively short time before it has cleared the flask opening, I don't even think it accelerates to that great a speed. Clarification: a thermos is more or less a best-case scenario, since the valve at the top is going to be much weaker than the flask itself. A plastic bottle is worst-case, because it is going to shatter and eject plastic splinters.