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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."
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Killer Apartment Vs. Persistent Microwave Exposure?

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  • by AlexiaDeath ( 1616055 ) on Monday March 01, 2010 @07:05AM (#31313844)
    Dont buy it. You will worry yourself sick whatever we say.
    • by DingoTango ( 623217 ) on Monday March 01, 2010 @07:10AM (#31313870)
      Agreed. Notice that you referred to the space as a "killer" apartment.
      • by Z00L00K ( 682162 ) on Monday March 01, 2010 @08:03AM (#31314158) Homepage

        Don't worry until you have had a radiation team doing measurements in your apartment and found out that the levels are near what's considered unhealthy.

        But be prepared to find out that your apartment is considered unfit for living.

        • by Cryacin ( 657549 ) on Monday March 01, 2010 @08:05AM (#31314178)
          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!
          • by lorenlal ( 164133 ) on Monday March 01, 2010 @08:58AM (#31314552)

            Darn it, all I can find is aluminum foil!

            Curse you government! I see what you're doing!

            • by Anonymous Coward on Monday March 01, 2010 @09:41AM (#31314986)

              Alu-min-i-um, you insensitive colonial.

              No worries: if it was unsafe, I am sure that the cellular industry would tell you.

              • by FiloEleven ( 602040 ) on Monday March 01, 2010 @02:18PM (#31319316)

                The man who discovered aluminum in 1808, a British chemist named Humphrey Davy, first named it "alumium." When he published in 1812 he had renamed it to "aluminum," which is the name still used in America. So where did that extra "i" come from? Wikipedia has the answer.

                'An anonymous contributor to the Quarterly Review, a British political-literary journal, in a review of Davy's book, objected to aluminum and proposed the name aluminium, "for so we shall take the liberty of writing the word, in preference to aluminum, which has a less classical sound."'

                That's right. All of the haughtiness with which the British defend their extra syllable, all of the bloodshed spilled over the difference, and all of the mutual incomprehension that ensued is due to a change made against the discoverer's wishes based on the rant of an Anonymous Coward. If that isn't a successful troll I don't know what is.

          • by L4t3r4lu5 ( 1216702 ) on Monday March 01, 2010 @09:17AM (#31314744)
            No! That's the worst thing you can do! Have you ever seen what happens to a ball of tin foil when you put it in the microwave?!

            What you need are magnets! It's like how a motor works, but in reverse.

            No, not like a dynamo. More like the deflector dish on the Enterprise.

            Just don't cross the streams. Never cross the streams.

            Unless wearing waders.
        • by Alien54 ( 180860 ) on Monday March 01, 2010 @09:10AM (#31314676) Journal
          There are paints you can get which have metallic dust incorporated into them. This will act as shielding. You can also go with a "Luster Dust" which would give a metallic sheen to your current wall color. Or even a straight metallic wall paint. There is also metallic wall paper.

          see also Force Field Wireless [] for paint additive, although you could also experiment with various metallic powders on your own.

          Ditto Storm windows with metal frames and screens. Apparently prefinished flooring also contains metallic powder which can reduce wifi signals. The new double pane windows also have metallic coatings that can reduce wifi.

          Normal cell phone reception would have to come from the side of the building opposite where the transmitters are located.

          • Re: (Score:3, Informative)

            by AeiwiMaster ( 20560 )

            One protective paint is yshield.

          • by TopherC ( 412335 ) on Monday March 01, 2010 @10:54AM (#31316050)

            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.

            • by Creepy ( 93888 ) on Monday March 01, 2010 @11:54AM (#31317040) Journal

              Speaking of low level radiation, and specifically non-ionizing radiation like cell phones, popsci has an article [] about a guy that is hypersensitive to it. The online article is four pages (I think the print article was 10-12) and it does cover a lot of ground, including arguments from both sides. I kinda skimmed over it, myself, but if you care about this sort of thing it may be worth a read.

              • by the biologist ( 1659443 ) on Monday March 01, 2010 @12:51PM (#31317936)
                "On a walk last summer, he ran into one of his few neighbors, a man who lives in a cottage about 100 yards away. During their chat, the man’s cellphone rang, and Segerbäck, 54, was overcome by nausea. Within seconds, he was unconscious."

                The guy in the article only develops symptoms of exposure when he realizes he's being exposed. He's a paranoid lunatic to a severe degree. It is probable that medication will help him, but not until he accepts that the problem is internal not external in nature.
        • by HangingChad ( 677530 ) on Monday March 01, 2010 @10:36AM (#31315714) Homepage

          Don't worry until you have had a radiation team doing measurements in your apartment and found out that the levels are near what's considered unhealthy.

          Time, distance and shielding are your friends. But that's really immaterial here, the perception is what you have to consider. Not just for yourself but when you want to sell it sometime in the future.

          I can go on for hours about why it's safe to live under power lines, but if it's your house, it's not going to sell. I'd take a pass. Not because of the microwaves, but because of the resale issues.

      • by Sebilrazen ( 870600 ) <> on Monday March 01, 2010 @09:01AM (#31314590)
        Actually below the summary has the actual title of the submission as "Kickass Apt. vs. Persistent Microwave Exposure."
      • by tempest69 ( 572798 ) on Monday March 01, 2010 @11:55AM (#31317052) Journal
        Man, keep the apartment.. just think, you can place a bowl of popcorn kernels on your kitchen table, and try to catch them as they pop.. sure invite friends over, have some drinks. invite that cute girl with braces over so you can eavesdrop on peoples conversations. Get a pair of rabbit ears and let the microwaves power a jacobs ladder. Get some blinds, so you can turn off peoples cell phones in the whole area, then open them so you can really keep them cranky.
        Create a parabolic dish, so that you can nail some poor schmuck in jersey with roaming charges. (so poor that his cell phone charges for roaming)..


    • by Tim C ( 15259 ) on Monday March 01, 2010 @07:19AM (#31313918)

      In addition, if you are worried consider that future buyers may also be worried. Unless you plan to either die in the apartment or leave it to your children, resale ability and ease of resale may be things you wish to consider.

      • by noidentity ( 188756 ) on Monday March 01, 2010 @08:13AM (#31314224)

        In addition, if you are worried consider that future buyers may also be worried. Unless you plan to either die in the apartment or leave it to your children, resale ability and ease of resale may be things you wish to consider.

        Look on the bright side: if he really does die from the microwave radiation, he won't have to worry about resale value.

      • "Killer Apartment Vs. Persistent Microwave Exposure"?

        If the 'persistent microwave exposure' turns out a bad thing, the place may indeed be a 'killer apartment'... ;-)

        Re re-saleability - even if you plan to stay there in the long term, you should still make your offer reflect the antennae... ...after all, your current vendor already faces a lower sellability on the place because of the antennae. Bid lower and leave it to the vendor to decide whether and how much more time to invest to try and line up another

        • by umghhh ( 965931 ) on Monday March 01, 2010 @08:58AM (#31314554)
          • tell the current owner that you are concerned but your concern may go away if price goes down
          • sue the 'major cellular operator' till they move the antennae away to save time and money
          • sell apartment for a good price it deserves
          • profit
          • Re: (Score:3, Interesting)

            by Anonymous Coward

            Actually we made it against the law to remove/prevent building of cell-phone antennae based on medical arguments. Thank Congress.

            • by ElectricTurtle ( 1171201 ) on Monday March 01, 2010 @12:01PM (#31317162)
              That's because those arguments are utter crap. Just like there was an article on /. not long ago (too lazy to search for it) about a transmission tower in Africa where a group of crackpots were saying they were allergic to its signals; however, they found out later that it had been turned off for weeks during a period they supposedly had 'symptoms'.

              It's non-ionizing radiation. It doesn't impart enough energy to have harmful effects.

              So yeah, thank you, Congress. At least you get things right occasionally.
              • by ChrisMaple ( 607946 ) on Monday March 01, 2010 @05:35PM (#31322486)

                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.

          • If you're discussing bugs, antennae is correct. If you're talking radio, however, it's " antennas []".

            Also, recall that the power density drops by the square of the distance from the antenna. So, if you measure the power at one micron away from the antenna, it will be twice the strength you'd get if you measure it two microns away. Extend this out, and at 3 microns, you're down to 1/8th the power, 4 microns = 1/16th. At 20 feet, you should be all the way down to 1 / 3,716,121,600,000th the original power,

        • by TheCarp ( 96830 ) <sjc@carpanet.PERIODnet minus punct> on Monday March 01, 2010 @09:02AM (#31314598) Homepage

          You are assuming that any other potential buyers even notice the cell towers. I garauntee about 90% of them see that they have full bars on their phone and think no further of it.


    • Get a gun. (Score:5, Funny)

      by Anonymous Coward on Monday March 01, 2010 @07:24AM (#31313952)
      Get a gun. Then, make an appointment with the landlord. Explain your fears and phobias (about microwave radiation) to the landlord. Wave the gun back and forth while you are talking.

      Ask the landlord to relocate the cell-phone towers.

      This strategy is quite effective in dealing with obstinate landlords. I should know since I'm serving time for 1 count of voluntary manslaughter.

      • by Red Flayer ( 890720 ) on Monday March 01, 2010 @09:13AM (#31314696) Journal

        Get a gun. Then, make an appointment with the landlord. Explain your fears and phobias (about microwave radiation) to the landlord. Wave the gun back and forth while you are talking. Ask the landlord to relocate the cell-phone towers.

        This strategy is quite effective in dealing with obstinate landlords. I should know since I'm serving time for 1 count of voluntary manslaughter.

        Wait... if you're serving time for voluntary manslaughter, that means your strategy is NOT effective, since obviously the landlord did not do what you wanted him to do (otherwise, why shoot him?).

        But then again, you have a gun and you're willing to use it... I'm sure your strategy is the best strategy ever. No really.


        Please don't hurt me.

    • Every time you do you are holding the antenna of that right next to your head. Yes it's lower power, but there's an inverse square distance law at work to, so the intensity is massively greater than that from the one 20 feet away. So either buy the apartment, or stop using cell phones. They are the only two logical choices.
      • Re: (Score:3, Informative)

        by umghhh ( 965931 )
        The actual time you are exposing yourself to radiations from your mobile phone is at two different times:
        • location update
        • when you are talking over it

        this compared with your constant exposure to radiation while being inside a microwave oven of your 'killer apartment' is another exposure altogether. Besides all this - just thinking of possible even if unlikely danger is going to make him sick anyway. If that does not his girlfriend will. Oh wait we are on /. - forget it. Go on buy it!

    • Re: (Score:3, Interesting)

      Dont buy it. You will worry yourself sick whatever we say.


      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 o

    • by mcgrew ( 92797 ) * on Monday March 01, 2010 @10:18AM (#31315440) Homepage Journal

      You're probably right, since they've studied the hell out of the effects of EMF radiation for years and years and found no correlation between EMF and illness. There's nothing special about microwave frequencies, but people think there is because microwave ovens cook meat.

      Here's a study of one: My dad, like hundreds of thousands like him was an electrical lineman for forty years. He worked with alternating current next to voltages up to 90 kv. He couldn't wear a wristwatch because the magnetic fields would magnetize that steel parts, which stopped working.

      He'll be 79 this June, and he still goes square dancing every Saturday.

      He did get some cancers from radiation -- solar radiation, not EMF. Working outside for forty years gave him some minor skin cancers on his face. The big fusion generator in the sky puts your puny EMF to shame. Worried about cancer? Stay out of the sun and don't smoke cigarettes.

  • Easy (Score:5, Funny)

    by acehole ( 174372 ) on Monday March 01, 2010 @07:06AM (#31313850) Homepage

    Tin foil suit.

  • Insert small coil (Score:5, Interesting)

    by DiamondGeezer ( 872237 ) on Monday March 01, 2010 @07:08AM (#31313864) Homepage
    If you're that close, you should be able to put a small coil of wire in your apartment and induce a nice free electric current. It won't make you popular with the owners of the antenna but what do they know? Otherwise no, I don't see a problem with RF.
    • Re: (Score:3, Interesting)

      by Angstroem ( 692547 )

      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.

  • by tangent3 ( 449222 ) on Monday March 01, 2010 @07:08AM (#31313866)

    ...for your problem.
    Right here: []

  • I'd pass (Score:4, Insightful)

    by mariushm ( 1022195 ) on Monday March 01, 2010 @07:10AM (#31313872)

    I wouldn't risk living there.

    As far as I know (and I'm no expert, just good at googling) , the radiation levels from antennas are relatively safe about 3-5 meters away from them but depending on the type of antenna their beam can kind of focused in one direction so that 3-5 meters estimation could mean a measurement ouside the beam direction and if the apartment is inside the beam the radiation could be above safe levels. For example, I've heard that in my country, if you live on the last floor of a building and an antenna is above, the antenna must be on a pole at least 2-2.5 meters high so that distance between the apartments below and the emitter is around 3 meters.

    Cellphone antennas would not be uni-directional so there shouldn't be any focused beam or whatever it's called but who knows what other antennas will be installed in the future on the same pole.

    So from a radiation point of view you may be safe, but you never know how sensitive you are or how sensitive your family / children etc will be.

    Second, while you may not care so much, the property will be harder to sell in the future because of that antenna.

  • Buy it (Score:4, Funny)

    by edittard ( 805475 ) on Monday March 01, 2010 @07:12AM (#31313880)

    1) Buy it.
    2) Sue phone company
    3) ...
    4) profit!!!!!!!

  • by TheDarAve ( 513675 ) on Monday March 01, 2010 @07:18AM (#31313910)

    There is a product called Scotch-Tint that is a EMF reducer for windows. Combine that with some metallic fabrics on the walls on that side. is one of many suppliers for those products. I've used a conductive plastic from those folks to make a shielded rack for some RF sensitive equipment.

    • Re: (Score:3, Funny)

      by gparent ( 1242548 )

      There is a product called Scotch-Tint that is a EMF reducer for windows.

      Does it work on Linux?

  • by Moskit ( 32486 ) on Monday March 01, 2010 @07:22AM (#31313936)

    Even if you get some information from /. and you buy it, you will need to explain that it's safe to every visitor who notices these antennas.

  • by George_Ou ( 849225 ) on Monday March 01, 2010 @07:22AM (#31313942)
    The facts about urban wireless towers is that they're very low power because of the high population density. They use very small cells in urban towers to achieve a very small coverage radius so that they can put up more towers in the city and reuse the same spectrum. Furthermore, just being in-doors cuts the power level 10-fold and I'd really doubt that you're getting more than -40 dBm which is equivalent to 100 nanowatts of power even if you're outside the windows. My Wi-Fi Access Point is 5 feet from me and it's got a power level of -13 dBm which is about 1000 times stronger than a -40 dBm signal. Now if you think that's high, your cell phone probably has a signal strength of +10 dBm which means the power density is 100,000 times stronger than a -40 dBm signal. And if you think the phone is dangerous, check out this article from me [] and this article []. So really, worrying about that cellular tower is just silly. If you're really worried about it, buy one of those $100 "Electrosmog" meters and measure the signal strength yourself at various places.
    • by matt4077 ( 581118 ) on Monday March 01, 2010 @07:45AM (#31314042) Homepage
      I find it interesting that after many years of stories about the impossibility of cellphone radiation having any damaging effect due to its low power, we suddenly hear this story about the positive effects it has. One of the two can't be true. I don't share the paranoids' obsession with radiowaves, but I'd like to know what if anything was wrong with the earlier assessments.
      • Re: (Score:3, Interesting)

        by George_Ou ( 849225 )
        The earlier "assessments" were based on weak studies and half truths ( All the studies that found potential dangers were based on tiny sample populations. All the studies that showed no danger were based on massive sample populations.
      • Re: (Score:3, Insightful)

        by arielCo ( 995647 )
        Who says you can't have both? With traditional medicine, they're called side effects. Perhaps chemotherapy qualifies too (attack everything, hope the cancer cells die first).
  • by tokul ( 682258 ) on Monday March 01, 2010 @07:23AM (#31313946)

    Mobile company raised cell tower next to some village. Locals complained about health problems caused by this tower. When contacted cell company CEO replied:
    - That's nothing. Wait and see what happens when we turn it on.

    • by Mattsson ( 105422 ) on Monday March 01, 2010 @09:06AM (#31314636) Journal

      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.

  • by Serious Simon ( 701084 ) on Monday March 01, 2010 @07:33AM (#31313992)
    In 2004 the Dutch laboratory TNO investigated the influence of UMTS and GSM radiation on two groups of people, one with health complaints they ascribed to GSM base stations and one without. The tests were double blind. For both groups a small, but statistically significant relationship was found between exposure to "UMTS-like" radiation and the sense of wellbeing reported by the subjects. This result was a disappointment to the Dutch government, that had commissioned this investigation. They had subsequent research done by a Swiss institution which did not confirm the findings. Anayway, the city of Hoofddorp, where I live, forbids the placement of cellular base station antennas on top of residential buildings. I support this policy; better safe than sorry.
  • by Leghorn ( 44886 ) on Monday March 01, 2010 @07:44AM (#31314038)

    I work with high power RF for a living. There are a lot of variables that contribute to non-ionizing radiation. Proximity, transmitter power, antenna radiation pattern, materials between you and the antenna, etc. There are ways to estimate the field intensity, but unless you know all the necessary factors, your calculations could be off by orders of magnitude. Having said that, the poster who commented that urban cells are lower power is generally correct, however, in a major metropolitan area, the cell can have many channels active at once, and the effect is cumulative. ANSI C95.2 is the safety standard covering this radiation. It's pretty technical, but the gist is the licensee (in this case the carrier) is responsible for making sure they don't cook the public.

    The carrier must certify to the FCC that there are no publicly accessible areas that receive unsafe RF fields. The exact number varies by frequency, but generally there are two levels specified, one for publicly accessible areas and another for areas where personnel who have been trained in RF can work in levels above the public ones. These areas are normally calculated by the carrier prior to installation and they won't install if there's any chance they might exceed the safe levels.

    As an example, I did an RF survey at one location where there was a multiple-transmitter FM antenna installed on top of a building that was across the street from another taller building. We had three FM broadcast transmitters operating on this antenna with about 250 kilowatts of radiated power, and the measured levels in the building across the street were not over the limits for public access. This was about 150 feet horizontally from the antenna. The solar coating on the building's glass stopped enough RF that it wasn't a problem.

    If you want to measure it yourself, there are some inexpensive meters that are pretty accurate that will give you an indication of how much RF you're seeing. The one I have is this one: It's about $150. I've seen these for sale at Fry's.

    I have calibrated mine against a $5000 Narda commercial RF radiation meter and it's pretty close, certainly close enough for a "go/no-go" test which is what I use it for.

    • Re: (Score:3, Insightful)

      by rugger ( 61955 )

      Many of the solar coatings used on windows are electtrically conductive.

      This was probably why the glass was absorbing a lot of the FM radio energy.

  • Normally... (Score:5, Insightful)

    by DiSKiLLeR ( 17651 ) on Monday March 01, 2010 @07:49AM (#31314072) Homepage Journal

    Normally I wouldn't worry at all.

    But the fact that,
    1) It's only 20 feet away,
    2) It's in the same plane as you, and,
    3) It's pointed AT you...

    That worries me some more. Obviously you want to talk to someone who really knows this stuff, and can also measure the EM radiation in your future apt.

    I also assume its a 'killer' apt because its in a great location and its CHEAP. And of course, its CHEAP because everyone is scared of the antenna pointing right at it...

  • You can afford (Score:5, Insightful)

    by kenh ( 9056 ) on Monday March 01, 2010 @08:44AM (#31314456) Homepage Journal

    Wait a minute, you can afford a penthouse apt in manhattan, but you are unsure about the safety of living next to a cellular antenna array that (to use your words) is pointed right at your apartment, so you turn to Slashdot? I don't believe it.

    I also don't believe that any company would install a cellular antenna array and point it at a structure - it would seriously impact the coverage area of the antenna, and they could probably just as easily installed the antenna on a taller building and avoid interference...

  • by jcr ( 53032 ) <> on Monday March 01, 2010 @08:58AM (#31314546) Journal

    ..and you'll be fine.


  • Well (Score:3, Funny)

    by Dunbal ( 464142 ) * on Monday March 01, 2010 @09:07AM (#31314642)

    Your first hint should be that the apartment is for sale because everyone in it died of leukemia...

  • by Hurricane78 ( 562437 ) <deleted@slashdot ... minus physicist> on Monday March 01, 2010 @09:31AM (#31314892)

    If there isn’t a window on that side where the panels are, just get some wallpaper that filters them. You know: Tinfoil hat style. (Well, usually some kind of wireframe suffices, if it’s e.g. 1/3 smaller than the waves.)

    But if you want to know EXACTLY, you can always find out the energy (=frequency) of the radiation, and compare it against the bonding energy of e.g. proteins in your body (keyword Van-der-Waals bond) and others. But be aware that the quantum physics of this is often counterintuitive.
    Then you don’t have to rely on biased tests or people telling you their bias, but know it yourself.

    From what I remember, microwaves can only create 0.1-0.2 degrees Celsius of heating in the body. So less than (the infrared in) sunlight, but deeper penetrating.

    Or in simple terms: If you fear microwaves, you should have more fear of sunlight, as it’s much stronger. :)

  • Buyer's Market (Score:5, Informative)

    by RevWaldo ( 1186281 ) on Monday March 01, 2010 @09:31AM (#31314900)
    It's a buyer's market for luxury property in Manhattan right now. Express your concerns to the sellers and hint that you'll need to have a survey team out to test for EMF exposure before you'd consider buying. Build an image in their minds of 3-4 guys in Tyvek jumpsuits walking around with meters on the roof and in the halls and knocking on your future neighbor's doors. (There's no reason for them to wear Tyvek jumpsuits, but you get the idea.) They'll likely offer to drop the price in exchange for you not doing that. More than enough to cover the cost of shielding and chemotherapy.
  • Probably fine (Score:5, Informative)

    by VeriTea ( 795384 ) on Monday March 01, 2010 @10:26AM (#31315544) Journal
    I am a PE and have done hundreds of RF emissions studies on wireless facilities, including rooftop installations like the one you describe. My initial thought is that twenty feet would be an unusually small distance between the antennas and your window. It may very well be much larger then that (50' or more is more likely - and would have much lower emission levels) but seems closer due to the perspective of the surrounding panoramic view. If it were truly only 20', and the building hosted antenna arrays from many wireless carriers (and FM transmitters), then there is a very slight possibility that the levels in your apartment could be near the public exposure limit. This situation is quite unlikely however. Most wireless carriers have an independent RF emissions study performed on rooftop installations that include measurements of the pre-existing antennas, so if you reached the right person and were persuasive enough you might be able to get them to share that with you (very unlikely). Another poster recommended a cheap meter. I'm not convinced of their accuracy, but you could give it a try if it worries you. Someone else mentioned low-E glass and correctly stated that it blocks a significant amount of RF energy. If you have low-e glass then even 20' away would mean your apartment is below the public exposure limit.

Things are not as simple as they seems at first. - Edward Thorp