My understanding is that wearing a wrist strap will help reduce sparking between the conductors on the electronic equipment (assuming they are connected to the chassis that the wrist strap is also connected to) and the person. This is because there is a low resistance conductive path (not through the air) between the conductors and the person. However, a wrist strap won't necessarily help reduce sparking between the non-conductors (which have high resistance) on the electronic equipment and the person. Most of the material around electronic equipment is non-conductive, so why are antistatic wrist straps even used? How is static prevented between the non-conductive material and the person?