Microwaves

[luke]

Hi all,
At work today, we had an electrician come in for the yearly testing and tagging. After testing all of our appliances in our kitchen, he discovered that one of our microwaves has been leaking radiation. It's been leaking at 8.1mW per square cm. Apparently this is really dangerous. I've been working with this microwave for almost a year. Which just makes you wonder, how many people could have the same problem and not even know about it? Makes me want to get mine tested at home. Has anyone ever had theirs tested?

Yes I'm really bored by the way py:

[CarBroker]

How old is the microwave? I was told that newer microwave ovens don't leak... ?

[Steffo]

Well, this scared me, thinking about my 11 year old microwave and all, but I've found this, so I'm no longer concerned...

http://rabi.phys.virginia.edu/HTW/microwave_ovens.html

To quote a part of it...

Originally Posted by How Things Work - Microwave Ovens

March 26, 2004

While shopping for a new microwave I was asking the salesperson at a local store some questions regarding microwaves. He proceeded to tell me how dangerous they were and that they used to sell some sort of testers to see if the new microwaves they were selling "leaked radiation". He told me that they all did and that microwaves give off "harmful" radiation. He said that it affects the food that we cook in it and can cause cancer. He said "Think about it, when you get an x-ray the tech covers himself with a lead shield and here we are putting our food into this and there is no lead shield. Needless to say I did not purchase a microwave yesterday, and was wondering if you could please give me some insight on this and tell me is what this salesperson told me is true. Are microwave ovens really harmful? Do they cause cancer? What about the food, does it become toxic. A friend of mine is totally into all organic food and she "unplugged" her microwave years ago and never used it since. She swears it is harmful. Please help. Heating food in a pot is so inconvenient!! -- KO

The salesperson you spoke to was simply wrong. If you'll allow me to stand on my soapbox for a minute, I'll tell you that this is a perfect example of how important it is for everyone to truly learn basic science while they're in school and not to simply suffer through the classes as a way to obtain a degree. The salesperson is apparently oblivious to the differences between types of "radiation," to the short- and long-term effects of those radiations, and to the importance of intensity in radiation.

Let's start with the differences in types of radiation. Basically, anything that moves is radiation, from visible light, to ultraviolet, to X-rays, to microwaves, to alpha particles, to neutrons, and even to flying pigeons. These different radiations do different things when they hit you, particularly the pigeons. While "ionizing radiations" such as X-rays, ultraviolet, alpha particles, and neutrons usually have enough localized energy to do chemical damage to the molecules they hit, "non-ionizing radiation" such as microwaves and pigeons do not damage molecules. When you and your organic friend worry about toxic changes in food or precancerous changes in your tissue, what really worry you are molecular changes. Microwaves and pigeons don't cause those sorts of changes. Microwaves effectively heat food or tissue thermally, while pigeons bruise food or tissue on impact.

Wearing a lead apron while working around ionizing radiation makes sense, although a simple layer of fabric or sunscreen is enough to protect you from most ultraviolet. To protect yourself against pigeons, wear a helmet. And to protect yourself against microwaves, use metal. The cooking chamber of the microwave oven is a metal box (including the screened front window). So little microwave "radiation" escapes from this metal box that it's usually hard to detect, let alone cause a safety problem. There just isn't much microwave intensity coming from the oven and intensity matters. A little microwaves do nothing at all to you; in fact you emit them yourself!

If you want to detect some serious microwaves, put that microwave detector near your cellphone! The cellphone's job is to emit microwaves, right next to your ear! Before you give up on microwave ovens, you should probably give up on cellphones. That said, I think the worst danger about cellphones is driving into a pedestrian or a tree while you're under the influence of the conversation. Basically, non-ionizing radiation such as microwaves is only dangerous if it cooks you. At the intensities emitted by a cellphone next to your ear, it's possible that some minor cooking is taking place. However, the cancer risk is almost certainly nil.

Despite all this physics reality, salespeople and con artists are still more than happy to sell you protection against the dangers of modern life. I chuckle at the shields people sell to install on you cellphones to reduce their emissions of harmful radiation. The whole point of the cellphone is to emit microwave signals to the receiving tower, so if you shield it you spoil its operation! It would be like wrapping an X-ray machine in a lead box to protect the patient. Sure, the patient would be safe but the X-ray machine would barely work any more.

Returning to the microwave cooking issue, once the food comes out of the microwave oven, there are no lingering effects of its having been cooked with microwaves. There is no convincing evidence of any chemical changes in the food and certain no residual cooking microwaves around in the food. If you're worried about toxic changes to your food, avoid broiling or grilling. Those high-surface-temperature cooking techniques definitely do chemical damage to the food, making it both tasty and potentially a tiny bit toxic. One of the reasons why food cooked in the microwave oven is so bland is because those chemical changes don't happen. As a result, microwave ovens are better for reheating than for cooking.

[PH47]

ROFL @ the pigeon bits hahaha..

[max^power]

Cool, im not so worried about that crack in my microwave door now

[GreenMachine]

Was going to say... my microwave has had a huge crack in the door for years... But there's obviously nothing wrong with me!

[XRated]

Originally Posted by GreenMachine

Was going to say... my microwave has had a huge crack in the door for years... But there's obviously nothing wrong with me!

Ahahahaha hahah........ Hahah.... Ha.. Haa............. :monkes:

[Steve D]

Surely it's chemical change when you burn the food???

Originally Posted by Steve D

Surely it's chemical change when you burn the food???

Yea from whatever it is to carbon

[Homer1]

Originally Posted by luke

Hi all,
At work today, we had an electrician come in for the yearly testing and tagging. After testing all of our appliances in our kitchen, he discovered that one of our microwaves has been leaking radiation. It's been leaking at 8.1mW per square cm. Apparently this is really dangerous. I've been working with this microwave for almost a year. Which just makes you wonder, how many people could have the same problem and not even know about it? Makes me want to get mine tested at home. Has anyone ever had theirs tested?

Yes I'm really bored by the way py:

So you didn't notice the extra head on your shoulder????? _2:

[Tote]

Years ago as part of my job I had to test microwave ovens in the schools, after 4 years of testing every microwave oven in western NSW I only ever found two that lit up the tester. It was obvious that they had problems due to broken doors or faulty locks as well. So if your oven is not obviously damaged it probably dosent leak.
Regards,
Tote

[outback_ute]

I think the best thing about microwave ovens is how they were invented, I don't know the full detail of the story but basically a guy in a lab working on microwave transmitters for communications gear noticed that when he was standing in front of the transmitter he began to feel warm!!!