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Join Date: Feb 2010
Posts: 29

How I Was Almost Killed

07/06/2012 5:58 PM

HOW I WAS ALMOST KILLED

Everybody knows about boiling water. Many people know that boiling water splashes everywhere and whatever it touches, it burns.

Boiling water is normally predictable. You know it's hot and you inherently know that it is going to splash all over the place.

I recently saw something on the net where someone put a dish of water in the microwave, heated it for a while and took it out. There was no bubbling so the person didn't give it any thought.

SUDDENLY

the water splashed all over the place - IT EXPLODED ! Naturally, the handler was splashed and burned.

This occurrence is not an isolated one and scientists have replicated the event. They have found a couple things - water can boil at lower than 212 degrees, which we all recognize as its normal boiing point. The other thing they found was that in some cases even when water is above 212, it can exhibit conditions of NOT boiling - no steam, no bubbles.

I live in the midwest and the last week in June a heavy storm come thru, damaging lots of property and causing extensive power outages. Well over half million people are without power, including me. Generators are running everywhere you go. Living in the country, I also have a generator and I have to babysit it. I must run it for my refrigerators, since I have both freezer compartments full of meat. I have several Jerry Cans which I always have filled with gas for the generator and a lawnmower.

It's July and it's HOT, hotter than normal so everyone is sweating. I keep my generator in the walk-out ramp from my basement, and while some of it is sun lit, there is a lot of shade there, too. I have several gas cans in a metal cabinet there to provide shade for them. The generator is in the shade provided by the ramp walls. Besides that, there was enough shade for the one extra can that would not fit in the cabinet.It's in the high 90s and whenever you open any closed container that has been sunlit, there is pressure built up from the heat. Same with gas cans. You open the cap and it hisses as the pressure relieves. My Jerry can did this so I let it relieve. It spit out some gas so I let it further normalize as it depressurized. Eventually it stopped burping. I then set it on top of the generator so I could siphon the gas. By this time it had completely quieted down. Then I removed the big cap and put the siphon pump into the can. I started to pump to fill the bulb and then IT HAPPENED. Like the boiling water I mentioned above, the gasoline started boiling, EXPLODING OUT OF THE CAN, splashing everything in the area, including ME !

Fortunately, the generator, which had its shower of gas, was cool so none of the gas lit up. However, the gas was still bubbling, as it was still in a state of boiling, not as violently as before but it scared me to the point that had it ignited, I knew I would die.

I did a google search for - what is the boiling point of gasoline. I found that depending on conditions, gasoline can boil anywhere from 400 degrees DOWN TO 100 degrees ! I was within that lower end of the envelope where the gasoline boiled at around 100 degrees !

Bottom line is this - SUMMERTIME - BEWARE OF GAS CANS !

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Guru

Join Date: Sep 2009
Posts: 1056
Good Answers: 88
#1

Re: HOW I WAS ALMOST KILLED

07/06/2012 8:44 PM

This phenomenon both in water and gasoline as far as I know, is attributed to surface tension, and is helped by how slowly and evenly, heat is absorbed by the liquid. Microwaving is very good at that, and so is heating a closed container by external air. So liquid temp can exceed normal boiling temp. When something brakes the surface, (e.g. shaking), violent "boiling" begins. But it must be a small margin of temps that this happens. A bit higher temp will initiate "boiling" with the slightest pressure drop, i.e just after cap unseals, and before it is removed. You will of course notice the blow, but it will appear less forcefull, behind the tap, depending also of course, with how full the tank is. S.M.

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