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The Cause, Stopping the Pain, and "Electric People"

©1997 William J. Beaty


The simplest cure: before touching a doorknob, a car door, etc., first touch it with a metal car key. The fiercely hot spark will blast the tip of the metal key rather than blasting your sensitive fingertip, and it will painlessly discharge your body's charge. (Grip your keys firmly so no spark appears between the keys and your skin.) Once you've been discharged, you can safely grab the doorknob. However, if you walk around some more, or if you sit upon a plastic car seat, you'll again need to use the keys discharge yourself.

To prevent sparks entirely, we must somehow stop the charge separation process. This can be done by:

  • Changing your shoe soles to another type (try leather or ESD Shoes)
  • Using a humidifier to raise the humidity in the room
  • Spraying carpets, floors, and chairs with an antistatic coating
  • Wearing metal-coated shoe soles (try alum. foil, but it's slippery)
As with the car keys, the problem can also be prevented by discharging your excess body-charge in some way that doesn't cause pain. This can be done by:
  • Grabbing the metal car door as you climb out of the car.
  • Holding your car keys, a coin, or a metal pen, touch it to grounded metal objects.
  • Knocking your knuckles against doorknobs (fewer nerve endings, less pain.)
  • Wearing a carbon fiber tuft or small brush on a wrist bracelet
  • Wearing a metal thimble, touch it to grounded objects.
  • Wearing a grounded wire connected to a wrist strap
  • Installing a balanced-polarity ionizer fan (try the $50 static eliminator # MI9957, from C&H Sales)
  • Installing a conductive carpet, and wearing a conductive ankle-cuff connected to a metal shoe plate
The sparking problem is usually found in low-humidity locations, such as in air-conditioned office buildings. High humidity prevents the charge-separation which causes sparks. Raising the humidity in the environment stops the sparking. High humidity makes the surfaces of shoes and rugs slightly conductive, so the separated charges can instantly flow back together. Usually all of the "static electricity" will vanish when the RH is above 60%. If you live in a single house or apartment, use a room humidifier. Or just boil away a few quarts of water on your kitchen stove.

Or, if we spray the floor with antistatic liquid, this can do the same thing as raising the humidity. Antistatic liquids aren't magical, they simply make surfaces slightly conductive so the charge-separation cannot occur. Make your own antistatic spray by mixing a teaspoon of liquid fabric-softener into a quart of water.

Here's an idea you may wish to try. If you connect a carbon fiber tuft or small brush to a metal bracelet and wear it on your wrist, the tips of the carbon fibers will send your excess charge into the air. This technique is used on airplanes to drain away thunderstorm charge. Of course the carbon brush will not work as well as a wrist strap with a ground cord. But it should greatly reduce the size of sparks you encounter when walking around out in public. And at the same time, you can bump the carbon brush against any doorknob or car door before you grab it. In that case it will discharge your body entirely.

Electronics manufacturers use balanced-polarity air ionizers to eliminate sparks. These make the air itself into a conductor, but also they're expensive ($300 is typical.) NOTE: C&H IS SELLING ONE OF THESE STATIC ELIMINATORS FOR $50, # MI9957 (3/2004.) ANOTHER NOTE: there's a wearable ionizer advertised by NPA, but no price given.

Manufacturers also sell conductive shoe-straps and ankle cuffs which connect your body electrically to the floor. These are meant to be used with special conductive carpets, and they won't work well (or work at all) if the floor surface is made of wood, plastic, cloth, or other good insulator.

Shoe soles create the charge imbalance, so you can reduce the sparks by avoiding particular types of shoe soles. For example, rubber soles usually cause significant charge separation, while thin leather soles cause far less. Damp salty leather is best. Or wear sandals made from old tire treads (the black rubber is conductive.) Or wear no shoes at all, only wear thin socks or go barefoot.

You might consider coating your shoe soles with heavy adhesive aluminum foil. The foil halts the sparking because contact with metals can only generate a tiny amount of imbalanced charge. Unfortunately the foil makes your shoes dangerously slippery, and it leaves black scuff marks on plastic floors.

Simple solution: whenever sparking is possible, carry a metal object such as a pen or a set of keys. Hold them firmly and use them to touch any large metal objects. If the spark is blasting the end of your car keys, then it isn't burning a hole in your finger. And right after the spark has occurred, you can grab that metal without a problem.

For car-door sparks: if you touch the metal shell of the car as you climb from your seat, there will be no high-voltage buildup and no painful spark. This is good news for the passengers in your car who might not be carrying any keys or coins.

Another solution: always knock your knuckles against doorknobs before grabbing the knob. This won't stop the spark, but the spark is less painful when it bores into your knuckle rather than into your delicate fingertips. If you whack your knuckles hard, you barely feel the spark at all. After all, you're EXPECTING the small pain of your knuckle impact, and you are controlling the impact, so the pain of the spark isn't uncontrolled and unexpected. For some reason, unexpected sparks hurt far more than the ones you produce intentionally.

If you REALLY hate sparks, you might consider wearing a metal sewing thimble upon one finger at all times. Touch the thimble to the doorknob (or to other metal objects) and you'll feel no huge "zap." The spark will still occur, but the pain is gone. Note that the metal of the thimble MUST touch your skin, otherwise you won't stop the spark. If you want to experiment with thimbles in the ends of gloves or mittens, put the thimbles INSIDE the fingers of the gloves.

If you keep getting zapped at work, or if you keep crashing your computer, consider wearing a wrist strap with a wire connected to an electrical "ground." These are inexpensive on, typically less than $10, just search for keyword "electrostatic" and you'll find some. Buy the kind which has a metal "alligator clip" to connect to grounded metal. While you wear a grounded wrist-strap, your body cannot charge up at all. Or try an anti-static ankle strap to connect your body electrically to the floor. Really you are supposed to use these with conductive grounded carpets, but if your floors are slightly conductive, the ankle strap will help drain away your body's charge.

Created and maintained by Bill Beaty. Mail me at: .
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