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Definitions

Definitions adapted from IEC 61340-5:
Electrostatic discharge: A sudden transfer of electrostatic charge between bodies at different electrostatic potential, usually as a spark as the bodies approach one another.
Ohm: Unit of electrical resistance.
Ohm per square: An obsolete unit of surface resistivity of thin, single - layer materials. It was determined using a square probe that is no longer part of the new ESD standard in use in Europe.
Electrostatic conductive: Resistance (Rs, Rv or RG) of less than 105 ohm but greater than 103 ohm, usually measured with a DC voltage of 10 volt.
Electrostatic dissipative: Resistance greater than 105 but less than 1012 ohm, usually measured with a DC voltage of 100 volt.
Insulative: Resistance greater than 1012 ohm.
Static decay time: Time needed for a charge with a given potential e.g. of 1000 volt to be reduced to, usually, 10% of its initial potential. Used to better characterise materials of high resistance, usually above 109 ohm (1010 in IEC 61340-5-1).
Antistatic: Many materials hold an electrostatic charge after rubbing or separation from another material. Antistatic materials do not, or only very slightly, generate a charge (see low-charging). Astatic: A synonym for 'antistatic' (see low-charging).
Low-charging: Material which does not charge when rubbed with, or seperated from other materials. Note: The terms astatic and antistatic have previously been used to describe this property definition.
Surface resistance: The resistance, usually expressed in ohm, measured between two electrodes (of defined size, weight and hardness) placed apart on the same side of a planar material (such as a bench mat or a packaging film). The standard or the test method should be noted.
Volume resistance: The resistance, usually expressed in ohm, measured between two electrodes (of defined size, weight and hardness) placed on opposite sides of a planar material (such as a bench mat or a packaging film). The thickness of the material and the test method should be noted.
ESD protected area: An area, small or large, such as a work station or a factory, designed to allow handling of ESD sensitive devices with a defined level of risk of damage by ESD.
Ground: A large conducting body, such as the earth or the steel frame of a building or the hull of a ship, used as a return path for electric currents and as an arbitrary zero reference point.
EPA ground facility: A fixture, connected to ground or to the earth of the electrical mains, or to the steel frame of a building, to which are run one or more earth bonding points.
EPA earth bonding point: A grounded fixture to which EPA equipment may be connected or 'bonded', usually via a grounding wire or cord.
Earth grounding point: A connector such as a stud, usually fixed to a bench mat or wristband, to which a grounding cord can be fixed. Also known as a groundable point.