Standard Test Method for Static Electrification

Whenever two dissimilar materials are contacted and separated, excess electrostatic charge (triboelectric charge) will be found on these materials if at least one of the materials is a good insulator. This excess charge gives rise to electric fields which can exert forces on other objects. If these fields exceed the breakdown strength of the surrounding gas, a disruptive discharge (spark) may occur. The heat from this discharge may ignite explosive atmospheres, the light may fog photosensitized materials, and the current flowing in a static discharge may cause catastrophic failure of solid state devices. Electric forces may be used beneficially, as in electrostatic copying, spray painting and beneficiation of ores. They may be detrimental as when they attract dirt to a surface or when they cause sheets to stick together. Since most plastic materials in use today have very good insulating qualities, it is difficult to avoid generation of static electricity. Since it depends on many parameters, it is difficult to generate static electricity reliably and reproducibly.