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Any truth to discharging our bodies?

  1. Oct 26, 2011 #1
    there's at least one company that sells these "earthing" or "grounding" pads that are connected to the ground port in the wall socket. Allegedly they help "discharge" human bodies, which generally have too much charge, causing inflammation in the body.

    whether or not charge in the body causes inflammation is probably not appropriate here, but what about a human body carrying charge, and discharging it by being connected to the earth?
  2. jcsd
  3. Oct 26, 2011 #2
    Earth is a huge capacitance, which means it could store more charge given the potentials are the same comparing to human body, since V=Q/C. Therefore charge would continuously flow into eath until same potential is reached so that charge is in equilibrium.
  4. Oct 26, 2011 #3


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    Save your money, Pinch. They're full of ****.
  5. Oct 26, 2011 #4
    It is true. I used to work in the semiconductor industry and all of the manufacturing personal wore ground straps on the shoes and sometimes ground wires to the wrist as well. The body can pick up a static charge and will damage the semiconductor if discharged through it.

    I'm (very) skeptical of the medical claims though. There is always stuff like this being sold.
  6. Oct 26, 2011 #5


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    Note that the workbench pads also need to be grounded. The main issue is for the person and the pad to be connected so they are at the same potential, so there's no net voltage between the person and the pad that the senstive component is being worked on, otherwise current could flow between the person and the pad via the sensitive component.

    Unless there's some near infinite resistance between you and the earth, you'll slowly discharge any static that you've built up. You can't shuffle your feet across a rug, then wait 30 minutes and then try to get a spark by reaching for a door knob.

    I don't recall any claims that the guys that work on high voltage AC lines (wearing a Faraday cage like suit) having any health issues. They get onto the lines via a helicopter away from any earth ground source, using a rod then cable to equalize the potential (note it's an AC line, so the potential is cycling) between the line, person, and helicopter. Example youtube video:

    Last edited by a moderator: Sep 25, 2014
  7. Oct 26, 2011 #6

    I imagine the resistance of a rubber-soled running shoe is fairly high.

    The ground straps I mentioned had 10 MegOhm resistance, for safety reasons.
    Last edited by a moderator: Sep 25, 2014
  8. Oct 26, 2011 #7
    Electrostatically charged objects (such as humans) loose their charge to the air (especially if its wet), although it happens slower than if you are holding a metal ground wire. You don't have to be physically grounded to slowly loose electrostatic charge. The early pioneers in electrostatics, such as Coulomb, noticed this. They learned to run their experiments in the cold dry winter air or in vacuum to avoid charge leakage to air degrading their results.
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