Don - I once (foolishly) removed the radiator cap from a HOT car engine.
This was a car where the radiator filler neck was angled 45 degrees pointed
to the off-side of the car. There was no steam spewing out, no water
fizzling as I took the cap off. About 2 seconds after the cap was off, and
I was getting ready to look to see where the water was, about 1 quart of
212F water puked up out of the filler neck and landed in a solid slug 6 feet
from the car; about 2 feet from where my 5-year-old was standing, watching
me. Don't have to tell me twice!!!
Lannis
>
> Subject: HOT WATER!!!!!!!!!!!!!!!!!!!!!!!
>
>Anyone who uses a microwave oven to heat water should read this
>message...from the father of a recent burn victim:
>
>About five days ago my 26-year old son decided to have a cup of instant
>coffee. He took a cup of water and put it in the microwave to heat it up
>(something that he had done numerous times before). I am not sure how long
>he set the timer for but he told me he wanted to bring the water to a boil.
>When the timer shut the oven off, he removed the cup from the oven. As he
>looked into the cup he noted that the water was not boiling, but instantly
>the water in the cup
>"blew up" into his face. The cup remained intact until he threw it out of
>his hand but all the water had flew out into his face due to the buildup of
>energy.
>
>His whole face is blistered and he has 1st and 2nd degree burns to his face
>which may leave scarring. He also may have lost partial sight in his left
>eye. While at the hospital, the doctor who was attending to him stated
that
>this a fairly common occurrence and water (alone) should never be heated in
>a microwave oven. If water is heated in this manner, something should be
>placed in the cup to diffuse the energy such as a wooden stir stick, tea
>bag, etc. It is however a much safer choice to boil the water in a tea
>kettle. Please pass this information on to friends and family. (Mike J.
>Tucker, Safety Officer)
>________
>
>This may sound like an urban legend but it isn't. The physics is that a
very
>clean cup has no nucleation points to initiate the boiling, so the water
>can easily become superheated beyond the usual boiling point. If the
>super-heated water is then mechanically disturbed, like inserting a spoon
or
>adding your cocoa mix, the stored energy can be released all at once. Not
>all of the water turns to steam, only a small fraction, but it can blow the
>remaining hot water a significant distance... and faster than you can get
>out of the way, for sure! Beware!... and Take care!...
>
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