Static charge (electricity) is a fairly simple, but often misunderstood event. Briefly stated, a static charge is generated between materials through friction, pressure or separation of two materials. This process is called the Triboelectric Effect [tribo means rubbing]. A material that inhibits the generation of static charges is classified as low charging (anti-static). Low charging (anti-static) materials used to make these natural fill brushes include Wood, Hog Fill, Horse Hair and Goat Hair. These materials can be used in ESD sensitive areas as long as the brush remains in a liquid environment. In a dry environment, only conductive or dissipative materials should be used in ESD safe areas.