Killer Apartment Vs. Persistent Microwave Exposure? 791
An anonymous reader writes "I am considering buying a penthouse apartment in Manhattan that happens to be about twenty feet away from a pair of panel antennas belonging to a major cellular carrier. The antennas are on roughly the same plane as the apartment and point in its direction. I have sifted through a lot of information online about cell towers, most of which suggest that the radiation they emit is low-level and benign. Most of this information, however, seems to concern ground-level exposure at non-regular intervals. My question to Slashdot is: should the prospect of persistent exposure to microwave radiation from this pair of antennas sitting twenty feet from where I rest my head worry me? Am I just being a jackass? Can I, perhaps, line the walls of the place with a tight metal mesh and thereby deflect the radiation? My background is in computer engineering — I am not particularly knowledgeable about the physics of devices such as these. Please help me make an enlightened decision."
Insert small coil (Score:5, Interesting)
Re:Insert small coil (Score:3, Interesting)
We're talking about cell phone here, not military-strength microwave radar signals :)
Would really astonish me if he could even light up a energy-saving lamp with the cell-phone signal.
Re:No, he's not being a jackass (Score:5, Interesting)
Re:not expensive to use wire mesh (Score:2, Interesting)
Re:not expensive to use wire mesh (Score:5, Interesting)
Are there any laws against passive shielding inside your flat? After all, you could simply put standard metal office furniture inside your flat, and that would cause massive interference, too. I'd say, if the phone company doesn't want the signal to be blocked by whatever is inside a flat, it should put the tower somewhere where it won't be blocked by something inside a flat.
Re:Yes, you are being a jackass (Score:1, Interesting)
Well well I would not be that fast to say that this could not be an health issue. There is enough evidence that radiation can be hazardious. However we are not sure of what type and energy levels are unhealty.
Resently though it has been shown that mobile phones are a not that bad as first anticipated. On grown up it can hardly be an issue at all. Though on childen it's evident that a modern mobile phone does heat up their brain while beeing on a mobile phone. It's not known what the effects of this in the end are. But that is reason enough to be carefull.
When it comes to antennas of the kind you describe I have no Idea of the energy levels, but I do doubt that they would be any lower than of an mobile phone. If you want to make sure you can measure the energy levels and compare them to energy levels of a mobile phone and make your conlusions out from that.
Some people take this to extreems, but you might also consider usage of window blinds. Aluminium or some other neath loocking type. That would moste surely give you a shielding that is enough without being a jackass nutcase. Grounding would that be an totally overkill, i dont know?
You make an awful lot of money for an engineer (Score:2, Interesting)
If you can afford a penthouse apartment in Manhattan, you're making an awful lot of money for a computer engineer. Where can the rest of us get jobs like yours?
Re:The facts about urban wireless towers (Score:3, Interesting)
Re:If you are worried about it... (Score:2, Interesting)
Easy one. Just start wearing a tin foil hat. I'm sure some kind soul here would be more than willing to help you out!
Someone actually performed a study on this and discovered that a tin foil hat would only amplify electromagnetic waves!
I kid you not.
Re:cell tower next to village (Score:4, Interesting)
I've experienced a similar story but about a Wimax-tower.
The exact day that a Wimax-service went active in the neighbourhood of my girlfriends parents, a couple with "electro-allergy" in the area started having headaches and feeling nauseous.
The funny thing was, the tower had already been active at full power for several months while they measured coverage and did trial-runs.
Re:who would pay for such a study? (Score:3, Interesting)
This study is useless.
The authors don't realize any if not most laptop power supplies use direct conversion, the transformer is gone. Ballasts are a feature of nearly every flourscent light, have been for decades. 'Energy-efficient' is not the distinguishing factor for these transformers.
Low-power DC-DC convertors have been in common use for consumer electronics since the 70s, especially in anything with a vacuum-flourescent display; VCRs, microwave ovens, radio-alarm clocks, your car.
This article is, IMHO, full of crap. I can make that shit up in an afternoon with some great-sounding theories. All crap.
Re:not expensive to use wire mesh (Score:5, Interesting)
The FCC may have something to say about that though. If he is close enough, his mesh may block enough of the signal to put the antenna out of use.
Any passive blocking that he puts on the walls or windows as an owner is something that he can't he held liable for(as opposed to active blocking or putting up a billboard or similar). I'd love to see the judge's face when the cell phone company tries to explain how their antenna requires his apartment to be non-shielded to operate properly(ie - we need to beam the signal *through* it because we put it in a bad location). They are supposed to be placed in such a manner that they are clear of buildings and physical obstructions. Hence the reason they are almost always on a small tower above a roof top. One thing, though - if you shield your place from these frequencies, you won't be able to use your cell phone at all while at home. You *can* turn your house into a giant Faraday cage. But expect it to act like one as well. You likely also won't be able to use your radio or HDTV over the air. Nothing comes in means nothing gets out as well. (OTOH, Wi-fi in home would be secure - heh)
Also, the refit won't be cheap. That Scotchtint runs about $1000 for a 60"x100ft roll. EMI resistant mesh for the walls generally runs the same. Generally you have to re-plaster or put another thin layer of drywall over top of it, which is factored into that price. And of course, it has to be installed properly. At that range(feet vs hundreds of feet) it will generate a significant amount of current.
Possible? Of course. But in today's world, being without tv, radio, wireless, and so on in such a place in NYC would be horrendous. In fact, trying to sell a place that you purposely turned into that would probably make it just as hard to resell as if you did nothing at all. I'd just keep looking. Maybe there's a similar place a block or two over?
Re:...and pick a better title... (Score:3, Interesting)
Actually we made it against the law to remove/prevent building of cell-phone antennae based on medical arguments. Thank Congress.
Re:recent cellphone radiation reports (Score:3, Interesting)
Re:If you are worried about it... (Score:5, Interesting)
You tried your best, but missed the relevant points, sorry to say:
The inverse-square actually depends on the directivity of the whole lot. A point source is fine, a laser isn't.
Therefore, the 'proximity' isn't good neither. Roughly, considering your side of the head to be flat and the phone a point on that plane, you get half of the energy into your brain. That's not convincing, to me, because that's easily half a watt of RF that seeps through my brains. If I put my phone 20 feet away (let's stick to scientific units: 6 m), the point source would seep around 1 watt through a surface of a sphere 4*pi*r*r, that is around 100 square meters. With the average head diameter being around 22 cm, the surface of the head through which the energy seeps is around pi*r*r, that is around 0.04 square meter. So you'd get around 1/100*0.04, that is 0.0004 watt of RF radiation. That wouldn't bug me at all.
But I wouldn't buy the place nevertheless: Firstly, you don't know the actual RF-wattage as produced. It can be significantly above 1 watt. How about 100 watt? And then, you don't know the directivity of that antenna. If it focuses the energy into your direction, and the main beam has a diameter of 1 m at 6 m of distance, it would blow 4 watt through your brain, and that 24/7. A parabola antenna is very good at concentrating energy. The place is not good at all. Fingers off, it might be totally harmless (see above), and it might be bad for your health (see below). Better safe than sorry!
That's my advice!
Re:If you are worried about it... (Score:3, Interesting)
Dont buy it. You will worry yourself sick whatever we say.
Agreed.
Even if experts came to you in person and told you not to worry, chances are it would always be in the back of your mind. One of the things you want when you get a place is peace of mind.
I'm not a doctor and I do not worry about things like cellphones or WiFi access points; but having a cell antenna pointed at window from a few feet away would be dis concerning.
And as others already posted, if you ever plan on selling the place your customer base may have the same fears.
Sure if it's an incredible one-in-a-lifetime deal it's hard to pass up, but you have to ask yourself "why is the owner willing to part with it for a song?" My guess is if you ever want to sell it you'll have to drop the price to a sweet deal as well.
Re:Yes, you are being a jackass (Score:2, Interesting)
Haven't you seen the 'living in the age of wonders' videos from the 50s that showed kids swimming in pools that were being fogged with DDT?
Controlling malaria is probably a sane use of it, but they were way past that.
Re:not expensive to use wire mesh (Score:3, Interesting)
Re:If you are worried about it... (Score:5, Interesting)
Even though I'm skeptical that relatively low levels of microwave radiation could really be harmful, I thought I should point out that these metallic coatings or similar solutions do not absorb the radiation, they merely reflect it. Since complete coverage (floor, ceiling, windows, doors, etc) isn't realistic, you may easily reduce radiation overall but you might be allowing standing waves in certain locations, concentrating the radiation here and there, like hot spots in a microwave oven. An appartment is much bigger than a microwave oven, the walls are less flat, and there is more absorption etc. But the overall principle still applies to some degree. So I guess if I were worried enough about microwave radiation, still bought the apartment, but applied these reflective paints and such, then I'd also be worried about standing waves. Sniffing these out would be very time-consuming.
Invisible Threat? (Score:3, Interesting)
Re:Insert small coil (Score:1, Interesting)
At least the country that I live in have this practice outlawed.
It's called energy theft or something like that.
I'm not a lawyer, but I believe that in the U.S., when something from an a neighbor's property like, for example, a branch, extends over one's property, the property owner can deal with it as he likes. By that logic, if your apple tree is extending across the fence into my yard, I may harvest the apples or cut off that part of the branch, as I choose.
The property owner can give an easement that allows the neighbor to pass through his property in some way. Easements are often part of the deed to the property. For example, the lot my house is built on has easements for the electric, telephone, and cable companies to run underground cables to my house, as well as easements for the water/sewer service and an underground runoff pipe along the back side of the yard.
Absent an easement, I don't think the owner of the transmitter could prevent you from harvesting a little power.
Re:Yes, you are being a jackass (Score:3, Interesting)
The scar across my hand from holding a 3db gain 5/8th wave antenna when I transmitted on 6 meters at 580 watts tells you otherwise.
High power drunk QSO contesting is not a safe hobby.
Why its it not working??? CQ,CQ AAAAAAAHHHHGGGGAAHHH THAT HURTS!
Sideband is a harsh mistress.
Re:No, he's not being a jackass (Score:3, Interesting)
> 20W 3dB 6 meters the power density is 0.0086 mW/cm2
I tend to agree - most likely there is very little radiation actually reaching the apartment. Just get a cheap RF meter and check how significant the background radiation is compared to a mobile phone. Chances are that it is negligible - and that would answer your question.
Re:Placebo Effect (Score:3, Interesting)
I was going to say... "scientists are still out on the long term effects of low level electromagnetic radiation exposure" Due to the anthropomorphic condition, the fact that we're here, and the sun constantly emits "low-level EM radiation" is nothing that hasn't been a selective pressure to tolerate since forever.
It's like those people who are running around with EM detectors, get into a brightly lit area and freak out going "OMG! THERE'S A HOTSPOT OF EM RADIATION HERE!!!!"
It's like... anime tear face... you can SEE part of the EM spectrum you twit.
Addendum from original poster (Score:1, Interesting)
I am the anonymous coward who posted this piece. The antennas are sector antennas, not panel antennas.
Re:You can afford (Score:1, Interesting)
I live in a 6 story U-shaped building. Being on the top floor and having cellular antennae pointed at the unit is not improbable. Our building has them in rack arrays along all the roof edges of the building and the side corner edges. More antennae = more $ for the building management.
Re:...and pick a better title... (Score:4, Interesting)
Actually, being non-ionizing doesn't mean that it doesn't impart enough energy to have harmful effects. There are other harmful effects beyond having chemical bonds ruptured by EM fields. If the size of your body is near to or larger than a wavelength, your body will absorb some of the incident radiation. It heats your body. This is why microwave ovens have door interlocks. This is why people have DIED, cooked alive while working on microwave communication antennas.
My understanding is that cellphone systems aren't high power; you're likely to be safe. If you're really concerned, buy (about $300), rent, or borrow a field strength meter and find out.