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Electrical Shielding for the Homeowner? 96

Posted by Cliff from the aren't-we-bombarded-with-enough-radiation-already dept.
AugstWest asks: "As more research comes out showing that high voltage electricity sources can cause cancer and other health problems, I was wondering what the geeks among us could come up with for electrical shielding ideas. I've got a high-voltage transformer just off my backyard to power the train that also runs practically through my backyard, and it would be nice if I could somehow shield us from it. Of course, if the shield could also be an induction coil to sap power for my house, that wouldn't suck either..."
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Electrical Shielding for the Homeowner? More

Electrical Shielding for the Homeowner?

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  • Pb! (Score:1, Funny)

    by PunkOfLinux ( 870955 )
    And not peanut butter, either. Lead!!

  • Nine year old news for nerds (Score:5, Informative)

    by DaoudaW ( 533025 ) on Saturday September 24, 2005 @11:17PM (#13642145)
    As more research comes out showing that high voltage electricity sources can cause cancer and other health problems.

    Okay I RTFA because I thought this had been effectively pooh-poohed and was interested in seeing additional research. But TFA is from 1996!!?? and the poster has the audacity to claim this as more research!!?? Cliff, what were you smoking in you posted this? The other FA is concerned about breathing ions. Oh my gosh, I salted my beans at lunch and ingested ions!!

    This is really a new low for slashdot.

    • Re:Nine year old news for nerds (Score:4, Insightful)

      by toddbu ( 748790 ) on Sunday September 25, 2005 @12:20AM (#13642411)
      But TFA is from 1996!!??

      Obviously you weren't paying attention. It's clear that there's a conspiracy to cover up the truth here, because in nearly 10 years the [Clinton] White House hasn't commented on this issue. I for one am going to rush out and build a device to stop any more EMF from entering my home. I'll do that as soon as I finish building my equipment that prevents the last great White House coverup - alien anal probes.

      Seriously, I've thought about taking myself off Ask Slashdot, but it's like turning away when you're about to witness a train wreck. It's just too hard to ignore.

    • I went to a seminar on this topic at C-MU in the mid seventies where an industry rep was telling us how electric fields were harmless and that we could ignore them. One of my EE professors, Stan Charap, asked since they didn't care about the electric field then it should be OK to wrap a few turns of wire around his house and use the power for free. The rep immediately got upset and said "That would be stealing". He didn't seem to think his position was a little inconsistent.

      I think there have been a coup

  • Faraday cage (Score:4, Funny)

    by danpat ( 119101 ) on Saturday September 24, 2005 @11:23PM (#13642175) Homepage
    Easy, build one of these [wikipedia.org].
    Of course, you could also cover your body with aluminium foil, that way, you'll be protected when you leave your house too!
    • You stole my post. Almost exactly, even the link to wikipedia. Well, if you do build a faraday cage just remember not to put the latch on the wrong side of the door like on a recent MythBusters episode.
    • C'mon! A true Slashdotter might build a Faraday cage, not to protect him from potentially harmful electromagnetic fields, but to protect him from p***ed off neighbors when he fires up his Tesla coil and screws up their TV reception on Super Bowl Sunday.

  • My idea (Score:4, Funny)

    by yobbo ( 324595 ) on Saturday September 24, 2005 @11:24PM (#13642179)
    Tin foil hat...

  • Rent a Gaussmeter (Score:5, Informative)

    by HotNeedleOfInquiry ( 598897 ) on Saturday September 24, 2005 @11:26PM (#13642187)
    And survey your living spaces. When my daughter was a couple years old and the powerline/childhood leukemia thing hit the news, I did just that. I relocated the main feeder cable from my meter to my breaker box to get the field down to zero in her room. I was able to do it by just pulling some giant staples out of the cable and moving it without disturbing connections. YMMV, hire an electrician for anything more invasive.

    As to the stuff not on your property, I'll bet that it's still undetectable thanks to the inverse square law.
    In any case, if it's bothering you, the first thing to do is rent the meter and do a survey.

    • Re:Rent a Gaussmeter (Score:1)

      by Anonymous Coward
      You can also buy a little "emf pager" that beeps if you're catching deadly rays. I remember reading about a Gauss Mouse a few years back.

      Besides, wth are you worried about emf if you are sitting in front of a CRT all day?
    • I have an electric company transformer exactly two floors under me. It supplies the elecricity for at least our building and one other nearby building (about 30 apartments). A friend of the family that operates a gaussmeter for a living came over and made some measurements around the transformer and in my home and said I had nothing to worry about and the radiation from that transformer is extremely low. When I asked him what does this "low" means practically, he asked if I have some transformer. I plugged

  • More Slashdot pseudo-science (Score:5, Informative)

    by Futurepower(R) ( 558542 ) on Saturday September 24, 2005 @11:27PM (#13642195) Homepage
    Cliff, I've often thought that you are one of the best Slashdot editors. But this article should not have appeared on Slashdot.

    Slashdot often carries pseudo-science articles, especially recently. Slashdot editors need to be more careful about that. If you didn't listen in Physics class in college, talk to someone who did.
    • Power distribution equipment does set up pretty large EM fields. Don't believe me? Walk under a powerline holding a plain ordinary 4' fluorescent tube on a fairly dark night.


      There is a substation a few miles from my house that can light up a plain ordinary compact florrie if you stand within 5' of the surrounding fence.

      • This is really pseudo-science (Score:4, Informative)

        by jesup ( 8690 ) * <randellslashdot&jesup,org> on Monday September 26, 2005 @08:08AM (#13649558) Homepage
        High-voltage stuff does have significant fields - though any effect on humans is far, far from proven. The flourescent light trick is cool (and scary to some), but means little. The whole worries over power lines seemed to spring originally from the reporting over Love Canal. Most people don't understand electricity, and the idea of an unseen field flowing through their body is unnerving to them (irregardless of the facts).

        Most of the studies of power-lines have trouble accounting for the fact that housing prices right next to HV powerlines are noticably lower - originally mostly for esthetic and sound reasons, now also due to fear of the unknown. In addition to causing different demographics of buyers, there are other related issues. For example, when planning powerlines, they don't just draw a line across a map - they try to minimize the cost of buying the land. Guess what? Brownfields are cheaper, and industrial area have less people objecting than "virgin" suburban land. And once the lines are in, businesses are more likely to be willing to set up shop under/near HV power lines - esthetics isn't as important to them, price is. Businesses (especially in already-low-value areas) tend to be the ones most likely to release toxins (you don't often see that in farmland). Untangling all this is really tough.

        This causes a difference in demographics that's hard to account for. And even so, the demographics don't scream "cause".

        More to the point, the original commentor was correct - this question is at best misleading and at worst promotes yet more bad science thinking by assuming facts not in evidence. I wonder how many readers won't notice TFA is from 1996, or won't even read it and assume the poster is correct about "increasing evidence".
        • "Businesses (especially in already-low-value areas) tend to be the ones most likely to release toxins (you don't often see that in farmland)."

          Not that this affects your main point, but I think farms release more toxins than most other businesses these days. Crop dusters, particulates, diesel exhaust, etc.
    • Quasi-rationally, leakage of PCBs from old transformers would be the only risk. It has been suggested previously that what little correlation there is to high-voltage lines and cancer has more to do with living in an industrial dump than the powerlines.

      Look up the earth's electrical and magnetic field, add in the fields from the powerline, represent this as a percentage, then go find something else to worry about. You're more in risk of your computer falling on you.

  • A quick test (Score:5, Informative)

    by ColaMan ( 37550 ) on Saturday September 24, 2005 @11:37PM (#13642241) Journal
    Personally, I believe that there are a lot more things a lot more ruinous to your health than a couple of humming wires stung out in your backyard. However, saying that, we'll move on.

    Ok, so you have a power line to supply trains running along the back of your house. Exactly how hot is it? 25kV? 66kV? Check the insulators - anything longer than a foot (or so) is high voltage, anything less is likely 3.3kV or below.

    If you don't have a field strengh meter, get an average 36W fluoro, go out to your backyard barefoot at night and hold one end. Wave it around a bit - if there's any serious amount of power around, it will light up the closer you get to the lines. Check how much it drops off between the back of your backyard and your house.

    Field strength drops off with the square of distance, so unless you're directly under 300kV lines, you probably have more pressing things to worry about, like that clock radio near your head when you sleep. Or the electric blanket that's millimeters away from you. Or the colour TV (or monitor) that is basically a particle accelerator.

    If the wires are an appreciable height above your roofline, and you are still concerned, earth out your roof (properly, with a ground stake,etc). This will shield the bulk of your house. Personally, as mentioned before, I'd go worry about other things, such as the resistant bacteria thats cropping up, or the apparent dwindling oil supply, or whether N. Korea gets The Bomb.
    • "...or whether N. Korea gets The Bomb."

      Yeah, I worry about that too. Lets hope that Bush jr has just enough braincells not to drop it on North Korea.

    • Re:A quick test (Score:5, Informative)

      by hankwang ( 413283 ) * on Sunday September 25, 2005 @06:02AM (#13643389) Homepage
      Field strength drops off with the square of distance,

      Accidentally, you are be right here, but it is because of Coulomb's 1/r^2 law that applies to single point charges. For line-like charges, such as power lines, the field falls off as 1/r. With power lines, you actually have two line charges with opposite signs, that partially cancel out each other's fields. In that case, the field will fall off as 1/r^2 if you are further away from the lines than the distance between the lines.

      Summarizing:

      • point charge: field goes as 1/r^2
      • two opposite point charges (dipole): 1/r^3
      • line charge: 1/r
      • two opposite line charges (line dipole): 1/r^2

      I'll also mention that all this only applies to the electrical field. This electrical field is easy to shield out (grounded aluminum foil will probably do), even though I am rather skeptical of the health benefits. However, the huge currents in the power lines also create a magnetic field (falls of as 1/r^2) and that is almost impossible to shield unless you are willing to cover your house with mu-metal sheet (think $1000 per square meter) or several cm of mild iron. Again, I think this is more relevant for sensitive electrical equipment (microphones, guitar pick-ups) than for your health.

      • Yes, but H is 10^-9 magnitude less than E or something like that. I don't want to find my physics or electromagnetics books to find out for sure.

        There is no effort made really to shield MRIs, as it is not very practical. They're just kept far away from everything else that might be affected by them. Industrial MRIs are quite unshielded, too, except by distance. It's just easier to keep magnetically sensitive materials out of the area.

        When I worked at UCSD, I used to walk by the NMRI lab in Urey Hall outside
        • There is no effort made really to shield MRIs, as it is not very practical.

          An MRI magnet is a dipole, so the field drops as 1/r^3 instead of 1/r^2 as with the power lines. Moreover, it doesn't vary in time so it does not create inductive currents. You don't wear a lead apron when you get an MRI, and your body part is inches away from a rather strong magnetic field.

          Actually, the magnetic field goes through the body, that's the whole idea. :-) Lead wouldn't help. An iron coffin might shield out part of t

          • "An MRI magnet is a dipole, so the field drops as 1/r^3 instead of 1/r^2 as with the power lines."

            Yea, a magnetic dipole... really unusual...

            Good luck finding a magnetic monopole (IE a "north" pole magnet without a south pole). If you really do find one be sure to notify the Nobel committee right away so they can start getting the prize ready for you.
            • Yea, a magnetic dipole... really unusual...

              Write down the equations for the magnetic field around a linear conductor and come back then with your smart remarks. A magnet only looks like a dipole if you are far away compared to the size of the magnet, and that is typically not the case with 100 km long power lines.

  • 500 things more effective for better health/safety (Score:5, Informative)

    by antispam_ben ( 591349 ) on Sunday September 25, 2005 @12:10AM (#13642379) Journal
    I just read John Stossel's [liberals-are-cringing] book "Give Me A Break!" and it has some actual facts concerning personal risks, something quite lacking in the media, and that also appears to be a problem the poster and editor appear to have. So here, off the top of my head, are just a few of many suggestions, any one of which will have a well-documented, much better chance of both improving one's health and lengthening one's life:

    1. Fasten seat belts always when in a moving car.
    2. Don't drive under the influence of alcohol or mind-altering drugs.
    3. Quit smoking
    4. Stay upwind of smokers
    5. Eat less fat and less meat, eat more fruits and veggies, especially raw ones.
    6. Do some aerobic exercise (swim/bike/run/jog/walk/skate) several times per week.
    7. Trade the VW Beetle (or other bad-in-a-crash car) for a Volvo (or other good-safety-record-for-its-driver vehicle).
    8. Don't drive when drunk/drugged drivers are most likely to be driving.

    Okay, I'm sure there are 492 other things that many people commonly do that have a proven, more detrimental effect on life and health ELF fields/living next to high-voltage power lines that people were so worried about in the 1980's and 1990's (the real danger to living near such lines is if one falls and hits the ground - you could be electrocuted by walking away from it! Hop (keep your feet together!) away, don't walk). Even if it's "scientifically proven" (or even a very strong statistical correlation shown) that cancer rates are higher near 60Hz high voltage (electrostatic fields) or high current (generating strong magnetic fields) lines, there are so many other things that we KNOW are MORE risky that any cost-benefit analysis would dictate that it's better to spend thousands of times more money on these other things before you even LOOK at whether ELF radiation kills 0.0001 person per million per year, or if it's even as much as 0.01 person per million per year.

    Slashdot's new look looks serious. And especially with responses like this (ELF is NOT news, and it's NOT Stuff That Matters), I'll have to come up with a more serious tagline.
    • 7. Trade the VW Beetle (or other bad-in-a-crash car) for a Volvo (or other good-safety-record-for-its-driver vehicle).

      Ok, where exactly did you here that the Beetle is bad in a crash? Since when is Four stars [automotive.com] considered "bad"?

      And let's not forget that (1) crash avoidance is more important than trying to be a "bubble", and if we're going to toss around marketroid allegations as truth I'd rather a distinctive (i.e., visible) beetle over a "safe" volvo, or (2) the more important measure of a "by the numbers"
      • 7. Trade the VW Beetle (or other bad-in-a-crash car) for a Volvo (or other good-safety-record-for-its-driver vehicle).

        Ok, where exactly did you here that the Beetle is bad in a crash? Since when is Four stars considered "bad"?

        If I remember the specific 20/20 it was back before the new Beetle came out, years ago. So he is saying the old VW Beetle, the one with the air cooled engine in the rear.
      • Since when did "eat less meat / more vegetables" become "eating no meat and nothing but raw vegetables"?

        Do you like to take everything to its most extreme conclusion? Honestly, there is nothing within that sentence that on its own supplied the implication of going "all the way." You took that one and ran with it on your own. People can start to control their eating habits and get benefits without consulting a doctor. And by the way, "control" does not mean "eliminate all of one substance."
        • People can start to control their eating habits and get benefits without consulting a doctor.

          Not the sort of people who need to be told to control their eating habits, though. The same reactionary mind that looks at power lines too far away to detect without eyes or a camera as a threat will take an advice to "eat less meat and more vegetables" as a reason to toss their (and their family's) perfectly healthy balanced diet and become never-cooking vegans.

          You're right, though. There are other folk who can a
          • I don't eat anything that wouldn't, if given half the chance, try to eat me first. Vegetables are very good at freezing in position, but make terrible stalkers, and just don't have the killer instinct.

            That said, I suppose it would be possible to build a structure of laminated hi mu silicon steel around a residential dwelling providing both magnetic and electrostatic shielding so long as no windows were provided, the door(s) fabricated to minimize leakage, and special measures were taken at entry points fo

      • The safe one is officially the "New Beetle", not the "Beetle". The "VW Beetle", while only recently discontinued in Mexico, was not a four-star safe car, wheras the "VW New Beetle" is significantly more safe (if not any less horrible to look at).
      • Ok, where exactly did you here that the Beetle is bad in a crash? Since when is Four stars considered "bad"?
        Hmmm... my Mazda Protege5 (unranked) is a bit heavier/safer car than the Protege 4-door, which gets 5/4/3/5 compared to the Beetle's mere 4/4/5/3. And I think that's less safe than I'd like. And let's be serious: a 2005 Honda Civic 4-door gets 5/5/4/4. Now that's a safe car.
    • > "Use the product of mass and the integral of jerk, Luke."

      Use the force plus mass times a constant? Looks like someone didn't quite pass calculus.
    • 7. Trade the VW Beetle (or other bad-in-a-crash car) for a Volvo (or other good-safety-record-for-its-driver vehicle).
      Not so long ago, Volvo sales manager for Russia was killed by lightning in the middle of his backswing while playing golf near Karlstejn castle (Czech republic, Europe). Playing golf while storm is coming shall be also on your list.
  • 1. Don't use electricity, period. Especially all that nasty AC that runs throw all the walls in your house.
    2. Either deep underground or live in a Faraday cage (this may be tought without electricity).

  • Of course, if the shield could also be an induction coil to sap power for my house, that wouldn't suck either..."

    1) That is theft. Even induced current isn't free.

    2) I believe the coil would have to be placed pystically around the transformer, and the train company would be bound to notice that at some point. See #1.

    • pystically

      "physically", rather. Need to use that Google toolbar spellcheck thingy more often.
      1. No, it's not illegal - as long as you (and your coil) stay on your own ground and do not tamper with the power house. If you can tap power just by placing something on your own ground (*NOT* attached to the power house), then you are just "harvesting" stuff on your own soil. The argumentation is similar to harvesting fruits from the neighbour's tree if branches grow your ground (though only from those over your ground). In addition - if they complain - you can probably sue them for transgression as they ar
      • Forget all the bullshit explanations. Here's the deal about theft of service -- I will be simple:
        Is electricity something we normally have to pay for? Yes.
        If you don't pay, do you still continue to get power, or does the company shut it off for non-payment? They shut it off.
        Is the poster, among the dumbest people on all of slashdot, trying to take something that should be paid for? Yes.
        Is it theft of service? Yes.

        • Basically a power house comes in two versions: well shielded or (nearly) not.

          If there is (good) shielding, there is no health risk and you cannot tap the leaking field (at least not above academical level). Noone is transgressing or tapping anything.

          If the power house is not shielded, the owner is sending out emag fields into Cliff's property - unasked for. So what Cliff does with this on his own ground is up to his own. As long as he is not exceeding his property limits and (especially) not touching anythi
          • Your fruit tree example is faulty.

            Under most local laws in the US, any part of a tree that crosses the fence/propery line is legally the property of that propery owner. It doesn't matter that the trunk of the tree happens to be owned by the other property owner.

            Thus, while you normally pay for fruit, you don't have to pay for fruit you do not own.

            On the other hand, EMF is electromagnetic waves. Just like in the US it is illegal to tap signals that you normally have to pay for, such as satellite TV, it would
            • You write "Just like in the US it is illegal to tap signals that you normally have to pay for, such as satellite TV"

              Uh, no. There are supreme court decisions that say you can do this.
            • Under most local laws in the US, any part of a tree that crosses the fence/propery line is legally the property of that propery owner. It doesn't matter that the trunk of the tree happens to be owned by the other property owner.

              Are you sure about this? I did some looking on nolo.com about this, and, well...it's not clear. If a branch of a tree I own falls off and damages the neighbor's property, it's my responsibility (reasonable). If the neighbor decides he doesn't like the branches, and prunes them off, i
        • Bullshit!
      • point 1 is basicaly correct, even if point 1 is incorrect it's unlikely that a power company would complain because of the public hysteria over EMF, to make the complaint valid they would have to admit that enough power is leaking from their lines to make it worth while to steal which would fuel more public hysteria.

        I've heard of some places that had specific laws against inductive power taps, they would have great curiosity appeal, amase your friends back of the comic book type stuff put your not going to
    • 1. Yes, it is theft. There are laws on the books for this. This is because we have metered electricity instead of Tessla's idea of free wireless power beamed from power stations as electromagnetic waves...

      2. You don't need a coil to be placed next to the transformer. All you need is a properly pieced shape of metal. Think of a radio antenna - that's bascially a tool to steal power from the transformer. Granted, it's a small amount of power, but if you live next to a radio reciever, it's *quite* possi
  • Hmm, I wonder why this person is worrying about high voltage particularly? I mean, 60 Hz EM fields saturate his house already because of the electricity running all through the walls and ceilings. The fields are exactly the same frequency, photon energy, et cetera.

    Now, a 6000-volt (say) transformer has a field strength right next to it about 60 times higher than the field strength right next to a wall socket. But, thanks to the inverse square law, the field strength 10 feet away from such a transformer w
    • A simple wall socket won't do anything. If there's no flow of current, there's no EMF. Now, the sockets that have things plugged in to them...
      • Not quite, I think. The wires in the wall will function as antennae, with a terrible SWR, to be sure. They will radiate radio waves at 60 Hz, just like this fellow's worrisome transformer does even when the trains aren't running. So there will be a very small current all the time to supply the energy emitted as radio waves.

        On the other hand, as you point out, when he fires up (say) his electric range and gets 10 to 20 amps flowing through those coils on top -- look out! Not only does he have strong EMF

  • Book that will tell you what you need to know (Score:5, Funny)

    by Guspaz ( 556486 ) on Sunday September 25, 2005 @02:18AM (#13642861)
    This book [amazon.com] contains all the info you need for this project.
  • Listen: The voltage means nothing -- you get more walking across the carpet. 50/60 Hz means little -- it's dead slow compared to molecular vibration, and 'way to fast for chemicals. But if you want, just go buy a microwave leakage detector at RatShack. I'd be more worried about your cellphone.

    The XFO is a _good_ sign. They can't leak much and already have a Faraday cage around them. Best of all, an XFO is usually in the middle of a section, far away from those spark-inducing section isolation breaks.

  • I wear a Tin Foil Hat [wikipedia.org] to protect /me from the negative health effects of "high voltage electricity sources". As I side benefit no one can hear the voices in my head but me, and the government has stopped controlling my every move!
  • If you have large transformer close to home, you may need magnetic shielding, not electric one. First, try to estimate strength of magnetic field. Use simple open induction coil and multimeter for this. If you will find rather strong magnetic field, change your house or destroy transformer, because good magnetic shield for 60 Hz is difficult to create.

    Transformers, transmission lines, GSM base stations and radio/TV transmitters are very important things to check when you are looking for new home.

    I have 4 or
  • Stealing by induction is illegal, obviously, and can be detected by the power company/owner easily and exactly. Basically any loop that is passed through an electic field will create induction, which wouldnt interfere with the electric field anyway. I know an electrician that has gotten cancer playing catch the electricity, but, unless you are talking a REALLY strong electric field, and very close proximity, do what everyone else says and worry about the mold in the walls or the rampaging duck.

    • Re:EE eh? (Score:2, Insightful)

      by Lehk228 ( 705449 )
      how do you know the cancer was caused by electrical fields?
      • Has to do with the type of cancer, the way I understand it, though Im certainly not a doctor.
        • >Has to do with the type of cancer, the way I understand it, though Im certainly not a doctor.
          I think the parent question for you is in what way you understand it, and it appears that you don't.
  • Rather than trying to shield an entire house, just build yourself a set of Orgone accumulators for every member of the family and spend as much time in them as possible.

    The thin metal walls are sure to do as good a job attenuating 60 Hz EMF as they do re-radiating orgone energy.

    You also might want to consider placing them in the left hand middle section of you home and painting them green so as to get as much Feng Shui benefit as you can while you're at it.

    Seriously, there are a lot of very real environment

  • No case to answer (Score:5, Informative)

    by Daniel Rutter ( 126873 ) <dan@dansdata.com> on Sunday September 25, 2005 @05:27AM (#13643314) Homepage
    When your concerns are based on one old newspaper article and the word of a person who opposes fluoridation [mercola.com] and vaccination [mercola.com], and makes money by advocating various dietary quackery [mercola.com] (refined sugar's a deadly poison, popular "healthy" foods are hideously contaminated, chelation [skepdic.com]'s good for what ails you...), it behooves you to expend a bit more energy making sure your concerns are, in fact, justified.

    I suggest you start with the World Health Organisation [who.int].

    • ... doesn't mean something is good to ingest. There actually may be some truth behind the touted dangers of fluoridated water, aside from the whole matter of actually drinking something that really should only stay on your teeth for a while before being spat out.

      A google for "fluoridation sewage" or "fluoridation sludge" will give you an interesting look on where cities get the raw material to add fluoride to water, and it's not very appetizing, especially considering the trace amounts of heavy metals and o
      • Which body part should I cover with tinfoil to maximize its potential?

        • Which body part should I cover with tinfoil to maximize its potential?

          Whichever part you don't want to cook too fast. I'd suggest the hands and feet, for starters, but you may find that you'll need to cover other parts depending on your oven and which bits you like extra crispy.

          Oh... you're talking mind control... sorry.

          Remember, the real reason orgone boxes were outlawed was that they interfered with the mind control beams. Also, "shiny side out" is a piece of government misinformation, as that actua

    • The fluoridation argument was not a good one. I won't read the page because I really don't care about wether the man is right or wrong, as I don't believe that powerlines' EMF are generally harmful. But though it might have always been done in the US, a lot of european countries don't add fluoride to the water, and for a lot of good reasons.
  • As others have pointed out, this risk is massively overblown. That said, if you're truly paranoid, here you go: LessEMF.com [lessemf.com] They've got a complete line of electric shielding clothes, canopies, etc.: Personal EMF Shielding Devices [lessemf.com] They also have mu-metal cloth for making your own magnetic shield clothing.

  • Tinfoil (Score:2, Funny)

    by John Hasler ( 414242 )
    Make hats for your entire family (don't forget the pets!). It has to be real tinfoil, though. Aluminum won't do.
  • And replace with lead lined drywall, used for sheilding from Xrays and others.

    See http://www.radiationproducts.com/gypsum-board.htm [radiationproducts.com] for example, and other
    similar products.

    You may notice some problems with things like cell phone reception afterwards.
    • I do know it is a joke but wouldn't having all that lead around tend to be more harmful?
      Also wouldn't grounded wire mesh be more effective when dealing with EM?
      All and all I have to agree with majority of people here... I worry a lot less about EM than I do about slipping on ice while out walking... And I do live if Florida.

  • Wrong Idea (Score:3, Informative)

    by Ed Almos ( 584864 ) on Sunday September 25, 2005 @01:57PM (#13645354)
    Find either a physics or radio guy and ask them to explain about the inverse square law. Unless the transformer is underneath your house you need not worry.

    Ed Almos
  • Why shield the whole house? bricks and morter are not effected but EM; Instead wear cloathing made with a wire mess sown in and a the ubiquitus foil hat, that way you can take it with you.
  • Ok, so you have a big transformer near your backyard. Why should you consider it a problem ? Aside from the fact that "big" is a relative term (for train power it cannot be that big, since these are most likely in the 6-12 kV range, certainly not as one found attached to a EE transport backbone), what is of importance here is the fact that the frequency of the electric and magnetic fields is 50 Hz (oops, forgot you are in the USA, make that 60 Hz) and its 3rd and 5th armonics, hence, for you, 180 Hz and 300
  • Good diet and exercise should counter the effects.
  • You can order stuff from lessemf.com. They have magnetic shielding material too.
    I bought some from them to shield an inductor that was sensitive to nearby magnetic fields, but it didn't really help. Now I'm on their mailing list, though, and they have a lot of stuff that sounds like it's right in your market.

    What bothers me these days is front-loading washing machines. They have AC variable frequency motors and lots of unshielded computer control components in them, and due to a quirk in the FCC regulati

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