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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..."

9 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.

  2. 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.

    --
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    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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  3. 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.

  4. 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 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.

  5. 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.

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  6. 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.

  7. 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.