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Measuring EM Waves for Home/Office Safety?

Posted by Cliff on from the need-a-big-thermometer-for-that dept.

Q-Neb writes "I'm beginning to get freaked out by the degree of electromagnetic waves I know are floating through me at all times. I work in the computing hub of a small college, surrounded by wires, a wireless AirConnect LAN, and about 500 students constantly gabbing on their cell-phones. As of this weekend, our office has become overrun by ants, apparently attracted by the high microwave presence (and leftover Coke)... How can I measure the amount of airborne communication passing through my workplace or my home? (Am I just paranoid, or is 3Com really out to get me?)"

9 comments

  1. Re:Just for safety's sake... by Elm+Tree · · Score: 1

    I thought it was Major Leauge Baseball?

  2. Spectrum Analyzer by SEWilco · · Score: 1
    If your facility has a "spectrum analyzer", the strength of radio signals across many frequencies can be easily seen. Some recent radio amateur computer-interfaced receivers cover a wide range of frequencies and can do a less precise measurement.

    And if you're concerned about those low-power signals around you, perhaps you should take a walk in a residential neighborhood a mile or two from a radio/TV antenna farm that's blasting 50,000 watts on a dozen broadcast frequencies and the center of as many microwave links. After 50 years, the bright blue trees, the orange grass, and the giant rats will be obvious.

  3. Instruments by d2ksla · · Score: 1

    This company is in the same building as I work in, but I don't know a lot about them... http://www.enviromentor.se/

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    Freevo - Linux Multimedia Jukebox
  4. Well...where are you sitting? by psicic · · Score: 1

    Look, as long as the computers et al meets the European standards - as I live in Europe, I can only assume th US still uses them - then for the most part you'll be safe. Computers, wireless apps etc are quite, quite safe.
    But I do have one piece of advice. If your college/organisation is using lots of CGA, EGA and early VGA monitors (MGA is not included) then all you really have to watch out for is sitting at the rear and/or sides of the monitors. They used to emit huge amounts of electromagnetic radiation to the sides and back(because the front was well shielded). That's where your worry should be.


    As for the mobile phones...you have a point - especially in the US. Forunately, I doubt other people have strapped their mobile phones to your body. The amount of radiation is actually so small that the prooven dangers of such phones(i.e. eye cancer) are mitigated by the distance between yourself and another individual.

    8)

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    Concrete analysis...
  5. Just for safety's sake... by clark625 · · Score: 1

    Since you're obviously worried about the evil radio waves, I think it would be best if you wrapped yourself in aluminum foil. That way, you can create a Faraday cage around your body so that those nasty EM waves won't interfere with your internal workings. Make sure that there is absolutely _NO_ holes in your special foil suit, as they could allow waves to bounce inside. You'll just have to go without seeing or breathing for a while until all the waves go away. Sorry.

    --
    Long, cute, or funny Sigs are just another form of over compensation, used by geeks, nerdz, etc.
    1. Re:Just for safety's sake... by Nick+Soapdish · · Score: 1

      That and it keeps the government from stealing your thoughts!!!!

      *twitch*

  6. I already covered this the other day... by physics+major · · Score: 1

    However, just for completeness, I think that this post I made covered that point, and several others. Fear not.

    Obviously, my point is that the "Microwave Interference" has nothing to do with home microwaves. These studies have already been done, and having some layman shout "woohoo, it works fine with *my* microwave, I don't know what *they're* talking about" does nothing but propogate myths and false information.

    Similarly, people will wonder if this will cause cancer, but they would have much greater risk from their cellphone (say, almost nil), and similarly, much greater risk from their microwave,(which is to say, not much) when both of which are far safer than The Sun! (which people don't even think about, blah, blah, sunscreen, blah blah blah...)

    My point is that a little research and correct information could have saved us all from this garbage, ad-hockery, and mockery of what used to be science. Apparently I was born in the wrong era, or came to the wrong place.

    1. Re:I already covered this the other day... by lizrd · · Score: 2
      Thank you for posting this. I'm glad that there are a few other Physics people around here. I find people who know what they're talking about to be so much more interesting than the conspiracy theorists and sham science pushers that seem to predominate this forum.

      Here's the simple truth. EM waves with a wavelength longer than UV light (this includes everything we call light, IR or radio waves) won't cause cancer. They don't have enough energy to break DNA and therefore can't cause the mutations that lead to cancer. The only effect that these longer waves can have to to produce some heating.

      To give you an idea, of how minimal the exposure from devices like cell phones is keep in mind that most of these devices radiate RF power at 1 Watt or less into the open air (unless you put the antenna in your mouth at least 1/2 of the energy radiates away from your head). This contrasts with a microwave oven which produces 700-1000W of RF power and furthermore, has reflective sides to keep the waves in the oven until they are absorbed by the food. What this means is that it would be very difficult to heat something like your head with a mobile phone or wireless LAN. Your head is pretty similar to a plate with 3 dozen scrambled eggs on it. Think about how long it would take to warm said plate of eggs in a microwave oven. I'm betting somewhere in the neighborhood of a minute. Now imagine that the microwave is less than 1/2000th as strong and you've installed a liquid cooling system in the plate of eggs. I hope that I don't need to say any more.
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      I don't want free as in beer. I just want free beer.
  7. Radiation, Schmadiation by SoCal+Wally · · Score: 1

    As a former nuclear engineer and a current RF engineer a wireless carrier, I can tell you that the cell phone radiation should be the least of your concern. I have used a device called A NARDA EME meter to measure radiation at cell towers and in office buildings with antennas on top. The meter measures a broad spectrum of radiation including microwave, PCS, police band, 2-way, etc. It is fun showing the "scared" building tenants that there is more radiation coming from their lunch room microwave or their laptop than from the antennas or a cell phone at close range. Here's a little intel. When a digital (CDMA) phone is only being listened to by a user and not talked into, the transmit signal is almost nothing, so the radiation given off is practically nil. If you want your co-workers to be sensitive to your radiation fears, tell them to communicate with only short "yes"/"no" answers while on the phone. It's safer AND entertaining for you too!