Ah, the internet. Where else would we find answers to all of our random questions? Our latest internet research: Whether or not your cell phone can help you identify leaks in your microwave. The legend says that if you place your phone in a microwave and close the door, it will only be able to receive an incoming call if there's a leak. But is that true?
Paranoid about cell phone radiation? You're not the only one. But they aren't the first device to get people up in arms about radioactivity. Before cell phones, it was that handy dandy microwave.
So it kind of made sense when we heard about this microwave leak test: Put your cell in the microwave, close the door and try to call it. If it rings, there's a leak. If not, you're wave-safe. After all, the only shield between you and those TV-dinner-zapping rays is the microwave box and it's door.
Well it turns out we couldn't find a solid answer.
Crowd-sourced WikiHow says it's a moderately reliable way to check for leaks, yet the also crowd-sourced Wiki Answers says "no dice."
We're more inclined to believe Wiki Answers, but we want to know if any of our uber-smart readers have a solid answer. Let us know in the comments!
- EDIT: Duh, we forgot to tell you what happened when we tried it (Thanks, Letrent!). We put my iPhone in the microwave and called from the S.O.'s iPhone about 20 feet away on the sofa. It rang right away.
(Images: Flickr user sokole oko under license from Creative Commons, Flickr user turtlemoon under license from Creative Commons.)
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Comments (8)
Maybe some microwave ovens are better shielded than others. What happened when you tried it in yours?
Bad test. Microwave ovens work at around 2.45 GHz, and are shielded for this frequency. Cellphones work in the 800-1900MHz range.
A "better" test would be to put a wifi device in the microwave and see if you can ping it. Still not a great test, as the device's tx power is much lower than the oven's.
All microwaves allow a degree of leakage - I'm a network engineer and spend a lot of time with a spectrum analyzer. I can usually pick up a microwave oven from 2 rooms away. Per Wikipedia, the FDA says 5mW is the max for human exposure from the oven. Most seem to leak more than this, based on my experience - often 20-30 mW. Still not much to worry about, as your Airport base station puts out 100 mW. Of course, I've never seen the output from a microwave with a truly bad seal.
Bottom line: hard to conclusively test without a spectrum analyzer. If you want to try anyway, a wifi device would be better than a cellphone.
There is a big difference between "radioactive" and "radiation". Radiation is a transfer of energy and applies to all electromagnetic waves like radio, heat, light, x-ray, and gamma waves. Microwave ovens and cell phones are closer to radio waves, and are at the other side of the energy spectrum from x-ray and gamma rays. Now Radioactivity is a decaying particle, that gives off radiation. Not all radioactive substances are as high energy as uranium or plutonium, anything with potassium or carbon is slightly radioactive, like a banana, a brick, or your body.
Also, the Faraday cage a microwave oven uses is intended to absorb microwaves, and might not block all types of cell phone signals.
My cell phone rang in my nice, but 10 year old microwave at home, but did not ring in the crappy, 10 yr old compact one at my work.
What if your cell phone rings in there and someone answers it! Perhaps the Ghost of Leftovers Past... Then worry...
Microwaves aren't so much shielded as they are designed to operate at the frequency they're designed to operate at (approximately 2.45 GHz as willidiots stated). They're simply made of metal and the screen in the door operates as a waveguide beyond cutoff which prevents the RF inside from radiating outward to a large degree. However, as willidiots also stated, it is *very* easy to pick up a microwave on a spectrum analyzer, without even an antenna hooked up (for demonstrations with new hires we used to stick an unfolder paperclip inside a female N-type barrel connector on the end of a long RF cable and run a microwave, a Motorola FRS radio, cell phone, etc. You always pick them up if you know where to look).
And yes, I AM an electromagnetic environmental effects engineer. Or more accurately, I was for 6.5 years until June when I changed to a new position.
I don't know about leaks and whatnot... but I can tell you that 3 minutes is too long to cook your iPhone.
Unless there are holes in the metal screen or your microwave door is ill-fitting, it's basically impossible for it to leak. You know that metal screen behind the glass with the little holes in it? Micro waves are bigger than those holes, so unless there is a hole bigger than that somewhere, it's not leaking.
In fact, early microwaves didn't even have glass over the metal screen.