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Ohio Supreme Court Drawn Into Magnetic Homes Case

The Ohio Supreme Court will decide if a builder will have to replace magnetized parts of two couples' homes, even though they signed a limited warranty which did not specifically cover replacing positively- or negatively-charged building materials. After moving into the homes the couples found that something was not quite right. Their TV screens were distorted. Cordless phones ran into interference. Computer hard drives were corrupted. Soon after, it was discovered that steel joists in the homes had become magnetized."

14 of 462 comments (clear)

  1. I have to wonder... by Kiralan · · Score: 5, Interesting

    ... just how strong the magnetic field is, for it to affect the hard drive of a computer at any likely distance. It seems like metal objects would be flying through the air and sticking to the floor. Also, I have to wonder how a static magnetic field would affect most phones. Seems there would have to be an alternating field of some sort to do so. Finally, any links to the 'numbers' (field strength, gauss, whatever the proper term is)?

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    V for Vendetta: People should not be afraid of their governments. Governments should be afraid of their people.
    1. Re:I have to wonder... by Grishnakh · · Score: 5, Insightful

      Yes, something definitely seems fishy here. You have to have a really strong magnetic field to affect a hard drive from any distance. Are steel objects flying out of their hands and sticking to the corners of the room? And yes, magnetic fields should have zero effect on electronic equipment, unless it's moving (which creates an electric field). If the house is like those rotating restaurants, except much faster, and is spinning around a stationary phone, I can see how that would cause a problem...

    2. Re:I have to wonder... by wierd_w · · Score: 5, Informative

      but the casing of (all?) commercial HDDs is designed to attenuate magnetic fields. this is because there is a great big honking rare earth magnet built right into the drive, just inches away from the platter. It is used to drive the voice coil actuator that moves the head around. Having that just a few inches away from floppy diskette drives (now a rarity, but still) without such attenuation would have been "Bad, M'kay."

      to not only have sufficient magnetic flux at the platter surface, but also be sufficient to cause electrical eddies inside the platters due to the rotation, the walls would have to be several million tesla in magnetic potential.

      Flying forks and hallucenations would be occuring long before this would become a problem.

  2. Ceilings by Anonymous Coward · · Score: 5, Funny

    "After moving into the homes the couples found that something was not quite right. Their TV screens were distorted. Cordless phones ran into interference. Computer hard drives were corrupted." And, their tinfoil hats were stuck to the ceiling.

  3. Re:Why replace? by Cryacin · · Score: 5, Funny

    Gives a whole new definition to "Attractive home in desirable neighbourhood"

    --
    Science advances one funeral at a time- Max Planck
  4. Highly Suspect by bragr · · Score: 4, Insightful

    Have you ever tried to kill a harddrive with a magnet? It basically requires passing a rare earth magnet closely over the platters several times before the data is reliably damaged and if they had that kind of magnetic fields it would cause much bigger problems. And while I don't know to much about the properties EM radiation, I believe that magnetic fields don't interfere with radio waves.

    My guess is that its the steel beams themselves are causing interference with the phones, that they incidentally had hdd failures (they have lived there for like 6 years), and the the steel beams have slight magnetic field because a small amount of current is passing through them (electricians like to ground to steel beams instead of running a ground line back to power box and putting to ground their) and they blame that weak magnetic field for their problems.

    This is all purely speculation because they don't give any real details about the field.

  5. degauss it by Bork · · Score: 4, Interesting

    If its just a couple of beams, it can be degaussed using a arc-welded and a few wraps of the arc-welds cables around the beam. There is a more to the procedure but the tools are easy to obtain. Did this in the Navy, wrap a submarine in about 300 turns of cable and run a few thousand amps through them.

  6. Re:Why replace? by Anonymous Coward · · Score: 5, Insightful

    The summary reads like BS anyway.
    If they actually have magnetic mono-poles in their house they should sell them for millions of dollars, instead of complaining about it.
    No one describes a magnet as "positively charged".
    Also charge is an entirely different property than magnetism.
    It seems far more likely the beams are not properly grounded and are possibly acting like an antenna, causing all kinds of interference.
    And unless they mounted their hard drives onto the "magnetic" beams I seriously doubt the field is strong enough to affect them.

    Finally I have to wonder how would these beams get magnetized?
    Did the electrician wrap some power cables around it?

  7. HDD BS by retech · · Score: 4, Interesting

    I've got a bulk tape eraser. Which is an electro-magnet. Tried to erase a few laptop and 3.5 hdds with it. I could pick the drives up by it holding onto the scant bits of ferrous metal in them but was unable to blank any of them. I tried one drive for 3 minutes and it still booted an OS just fine. If they had beams that could corrupt their drives their keys, belts, zippers, furniture and every damn thing in the house with metal would be stuck to that wall before that drive got nailed. It's just normal lifetime use/failure of the drive.

  8. Re:Why replace? by icebike · · Score: 4, Insightful

    Bad wiring, perhaps? Running electrical wires in close proximity to the steel joists could cause magnetization of the joists over time. Iron and its alloys are pretty easy to magnetize in that manner./quote

    Last I checked we use alternating current in this country.

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  9. Re:Why replace? by Megane · · Score: 5, Informative

    Have you ever taken a hard drive apart? There's a couple of real nice rare earth magnets in there for the voice coil, less than 3 inches from the heads, and maybe an inch from the platters. It would take one hell of a magnet to equal that strength at any distance, much less exceed it. It takes a lot of magnetism to flip the fields in those platters. The heads can provide that strength, just over a very small area.

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  10. Re:Why replace? by plover · · Score: 5, Interesting

    And this would affect their hard drives and TV how, exactly?

    Seriously, if the beams were magnetic enough to cause the claimed damage to the contents of the house, they wouldn't have been able to separate them from each other in this construction pile you've theoretically stacked up. They wouldn't even have been delivered, because they wouldn't have been able to scrape them off the forklifts, or lift them from the truck beds. Other vehicles passing them on the roads would have been stuck to the sides of their trailers. Once delivered, the carpenters' hammers would have flown through the air, heads permanently affixed to the beams.

    Yes, they could be magnetic enough to disrupt a compass reading. The earth's field is maybe 60 microteslas, so it's not a high bar to pass. But strong enough to erase a bit in a hard drive? The coercivity of the media is about 1700 Oe for cobalt, which takes a lot stronger field than that.

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    John
  11. Re:Why replace? by lurker1997 · · Score: 5, Informative

    The whole thing is BS. I work (mostly used to work) with MRI equipment, both supercon and smaller permanent magnet based instruments. I have some permanent magnets for building MRI machines that have a surface field strength of about 0.5T (5000 Gauss) which would crush your finger to a pulp if it ever got stuck between them, and are all but impossible to separate if they ever get near each other. I have routinely used a PC within a few feet of these without any ill effects. If I had to guess, the 5 Gauss line, normally considered the safe distance for magnetic storage media, is maybe a foot. If the steel beams in this house are magnetized, I would be amazed if the remanent magnetization was even 5 G. No chance of there being such a large field (this is 10x earth's field) more than a few inches away from the beams, regardless of their magnetization. Furthermore, a permanent magnet would have no effect on cordless phones of any kind. A static magnetic field has nothing to do with a 900 MHZ or whatever radio signal coming from the phone.

  12. Re:Why replace? by ace123 · · Score: 4, Funny

    Evidently, the coercivity of the media who reported on this story was high enough to be affected by these magnetic homes.

    (Sorry, it was only until after I read your comment that I discovered which type of media you were referring to.)