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Electrical Shielding for the Homeowner?

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..."

20 of 96 comments (clear)

  1. Nine year old news for nerds by DaoudaW · · Score: 5, Informative

    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.

    1. Re:Nine year old news for nerds by toddbu · · Score: 3, Insightful
      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.

      --
      If you don't want crime to pay, let the government run it.
  2. Faraday cage by danpat · · Score: 3, Funny

    Easy, build one of these.
    Of course, you could also cover your body with aluminium foil, that way, you'll be protected when you leave your house too!

  3. My idea by yobbo · · Score: 3, Funny

    Tin foil hat...

  4. Rent a Gaussmeter by HotNeedleOfInquiry · · Score: 4, Informative

    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.

    --
    "Eve of Destruction", it's not just for old hippies anymore...
    1. Re:Rent a Gaussmeter by Telecommando · · Score: 4, Informative

      Besides, wth are you worried about emf if you are sitting in front of a CRT all day?

      Really. Your TV, CRT and anything in your house with an AC motor in it exposes you to far more EMF than the power lines.

      http://www.emfs.info/Source_Appliances.asp

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  5. More Slashdot pseudo-science by Futurepower(R) · · Score: 4, Informative

    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.

  6. A quick test by ColaMan · · Score: 4, Informative

    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.

    --

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    1. Re:A quick test by owlstead · · Score: 2, Funny

      "...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.

    2. Re:A quick test by hankwang · · Score: 4, Informative
      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.

  7. 500 things more effective for better health/safety by antispam_ben · · Score: 4, Informative

    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.

    --
    Tag lost or not installed.
  8. what's up with the voltage? by Quadraginta · · Score: 2, Funny

    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 would be less than the field strength 1 foot away from a wall socket.

    And...he probably spends hours and hours within 1 foot of a wall socket, and isn't likely to be within 10 feet of the transformer very often at all...I mean, unless the transformer fascinates him strangely or something...

  9. Book that will tell you what you need to know by Guspaz · · Score: 4, Funny

    This book contains all the info you need for this project.

  10. Stossel likely meant old VW Beetle by jsimon12 · · Score: 2, Informative

    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.

  11. No case to answer by Daniel+Rutter · · Score: 5, Informative
    When your concerns are based on one old newspaper article and the word of a person who opposes fluoridation and vaccination, and makes money by advocating various dietary quackery (refined sugar's a deadly poison, popular "healthy" foods are hideously contaminated, chelation'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.

  12. Good topically on teeth... by StupidKatz · · Score: 2, Interesting

    ... 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 other rather toxic materials that just aren't feasible to remove from the "product". Then consider the possibility of skeletal fluorsis, which occurs when too much fluorine is ingested, which is where the skeletal bones basically rot/disintegrate.

    Vaccination isn't without its dangers, although for the most serious viruses, polio, etc., the vaccination risk seems more than made up for. Refined sugar isn't a wise thing to stuff into your body, either. Maybe the guy is going overboard (haven't read about him, specifically), but there is certainly a grain of truth behind all that "whacky quackery".

  13. Re:theft of service by Profane+Motherfucker · · Score: 2, Interesting

    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.

  14. Wrong Idea by Ed+Almos · · Score: 2, Informative

    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

    --
    The more corrupt the state, the more numerous the laws. - Tacitus, 56-120 A.D.
  15. This is really pseudo-science by jesup · · Score: 3, Informative

    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".

  16. Re:clueless? by SuiteSisterMary · · Score: 2, Informative

    Didn't the sat thing come down to 'you're free to recieve the signal, but breaking the encryption is illegal?'

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