You can tribocharge test these items with a field meter prior to designating them okay for use. And a last alternative, would be to invest in ionization that would control the charges from these items. KEY You want to identify the mat material that is best for your particular application. There is a concern with hard mats and that is with charge retention. It is more difficult to dissipate a charge from a charged material onto a hard mat than it is a soft mat.
Soft mats are superior to hard mats in removing charges.
This would imply that the shelves be grounded. This will ensure that the packaging won't be charged at a potential other than ground, thereby minimizing the occurrence of an ESD event when handling stored items. There is no mention of wire gauge. The wire used to connect the common point ground to equipment ground shall be of sufficient strength not to be inadvertently broken or disconnected. The wire shall be insulated and mechanically supported to physical structures to prevent mechanical damage.