October 13, 2015 @ 8:10 AM

http://www.esdjournal.com/articles/bracelets/groceryshocks.htm

Steve Fowler Fowler Associates, Inc.

  OK, this may sound minor and not even just a TN situation, but I need to know if anyone has advice on how to prevent static electricity from getting me every time I touch metal. I came from FL, where humidity is high and didn't have a problem. Now, with the cooler weather and low humidity, I am almost in pain just going to the grocery store picking up canned goods! Forget about opening the milk case. I did hear that putting a dryer sheet in your pocket may help. Is this true? Any suggestions would be welcome. It hurts!!"

 

 

 

This is typical of the comments about static electric shocks. Look over the links on the bottom of this page for more information on the problem.

The problem is simple:


1. The problem is Triboelectric static generation

2. The static generation is from the insulative wheels rolling on an insulative floor. Typically a new store with new carts cause the most problems.

3. The electrostatic charge is accumulated on the wheels inducing a high electric potential on the cart. If there is a platic handle on the cart, this potential is induced on the person. If there is no plastic hanle or if the person is touching the cart, the high potential is conducted to the person. In any case the person and the cart rise to high electric potential. 

4. This potential causes a painful or annoying spark discharge when the person touches the metal of the food racks or the product such as canned vegitables. It is like walking across a carpet and touching a metal door knob. ZAP! 

Lack of grounding of the store and racks is not the problem. In fact it is the grounding of the metal in the store that makes the energy of the discharge higher. It has a very low resistive path to ground of the discharge from the person. 


This problem can be reduced by the cart manufacturer by making the wheels conductive with carbon loading or conductive fibers. Many manufacturers either do not know this or do not want to add the costs.

Some stores have fairly successfully made attempts to solve the problem by adding drag wires on the carts.click here for the article

These wires work by the principle of passive ionization - described below. If the store where you are shopping does not have the drag wires, you can add your own using an aligator clip. 

 

 

 

 

 

Utilising Staticworx ESD flooring will certainly ease the situation and make shopping more pleasurable- even though you may get "shocked" at the checkout!