Microwave Hazards(A long but useful one)

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Joined Mar 13, 2001
I thought this would be worthy of note:

General Electric's response:

If you pass this on ... you could very well save someone from a lot of pain and suffering.
 
489
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Joined Mar 3, 2002
Thanks, I emailed this information on. Though why anyone would heat their coffee more than 1/2 - 1 minute....
 
1,389
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Joined Jul 24, 2001
Thanks for that Kimmie!

I think it's in the instructions that you must let ANYTHING stand in the micro 30sec after heating it!
 

phatch

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I smell an urban legend.

No first hand experience, only one company response, and even then, not a dominant builder of the product, Friends of Friends, unnamed alleged reliable sources, descriptions beyond science, fixes that are self contradictory and so on.


OK. First, to superheat water requires higher than normal pressure. A microwave is not a pressure cooker. It won't and physically can't happen. Microwaves aren't magic. They are very well understood. If the microwave was high pressure, The door would have blown out of his hand as he opened it and the water would have erupted out of the cup then as the pressure changed.

Second, cups and other common microwave items are flawed, They contain imperfections that cause liquids to bubble before they are technically at the boiling point. The liquid will certainly bubble. This is even before the scratches are taken into account. Surfaces are inherently imperfect. High school science teachers as authorities? Please. More on this in a bit.

Third, oven variances. Manufacturer and power of the oven isn't known. I have two microwaves. In the older low powered one, it takes about 1:45 to boil 1 cup of water. Sad, isn't it. In the newer one, 1 cup boils in about 40 seconds. It's much higher wattage too.

Fourth, Heat behavior. The science teacher's explanation is wrong. Thermodynamics is well understood. Look at the explanation. Bubbles release the heat? No. Water has a clearly understood reaction as it transitions from water to steam. It takes a known and fixed amount of energy for this to happen. The water will never pass the boiling point in temperature as long as it is liquid under normal pressure, which we have established as normal in the microwave. The water will continue to absorb energy to convert molecules to the steam state, but the temperature stays the same. This is why a steam burn, even though at the same temperature as the boiling water, is much worse. There is more energy in steam to burn you with.

Fifth, logic and the law. The person who had the accident does not verifiably have a GE oven. Why does an unaffiliated person write to GE for an answer on an unknown product? Why would GE give instructions on a product that wasn't theirs. They wouldn't. Corporate liability and lawsuits would destroy them.

Bogus through and through.

Phil
 
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Joined Feb 6, 2002
Well, actually Phil, this does happen with microwaves. If you have a container with very smooth sides, such as a new coffee cup, that does not allow the bubbles to form somewhere the water does superheat. I doesnt boil. It just gets very, very, very hot. The technique is to place a wooden skewer into the cup with the liquid you want to boil in order for the bubbles to form.

I have done experiments on this. Yes if your cup had a few imperfections on the inside the bubbles will form etc. etc. But with most of the cups tested the water did erupt out of the cup when it was jostled or being removed from the microwave.

There was also a show on the Discovery Science Channel on this. If everyone did these tests are wrong.............well, I don't know what to say to you. I wouldn't recommend running a test yourself unless you have a long instrument with a grasp at the end in order to lift the cup out of the microwave. This phenomenon can cause very severe burns. It is definately not bogus. (Oohhh I love a good discussion)

Jodi
 

phatch

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The jostling creates nucleation sites that form allow the bubbles to release. While true, it is technically possible, the weight of the water creating the necessary pressure, it's difficult to get it out to your face to blow up.

Also, it is a well known urban legend, even with some basis in possible fact.

www.snopes.com is devoted to urban legends. Very interesting reading. For specifics on this one see: http://www.snopes.com/science/microwav.htm Note that it's veracity is rated "sort of"

Phil
 

isa

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Joined Apr 4, 2000
It is true. There was even a piece about it on 60 minutes. The water will splash as soon as you will put a sppon or anything else in it. It's cause by a reaction that happends if water is heated pass the boiling point.
 
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Joined Jun 28, 2001
This very thing was mentioned on the local news here several weeks ago. They showed two women who had damage done from heating water in the microwave. Was NOT a pretty site!
 
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