Anti-static work surface
The anti-static work surface (refer to ESD TR20.20-2008, section 5.3.1-work surface) will provide a safe grounding path for electrostatic charges in the operator's general work area. The ESD work surface can be manufactured as part of the workbench or as a separate add-on product. In either case, the anti-static work surface should be grounded and have static dissipative properties, and the grounding resistance should be between 1×106 to 1×109 ohms. Eliminate applications that require LRU hard grounding. ESD S4.1 "ESD Association Standard Method for the Protection of ESDS Items-Workstation-Resistance Characteristics" describes the test method for working surfaces. The work surface can be grounded by using a current limiting resistor, which is usually 1/4 watt, part of 250V. The maximum rated voltage of the resistor defines the maximum working voltage of the surface. If the current generated from the voltage available on the workstation through the electrostatic dissipative protection work surface may exceed 5mA, it is recommended to use a series resistor to ensure personnel safety. For personnel safety, it is recommended to use a ground fault circuit interrupter (GFCI) in situations where personnel may be exposed to dangerous current levels.
ET&V personnel should check the continuity of the work surface during the initial certification. Thereafter, laboratory personnel can conduct inspections once a week. It is strongly recommended to use an electronic monitor to continuously monitor the integrity of the work surface.
The manufacturer's recommended chemicals and methods that will not damage the work surface should be used to clean the work surface.
ESD workstations do not accept exposed metal surfaces. If a conductive work surface is required under special circumstances, it must be hard grounded. If a painted metal workbench is used, the metal must be covered with static dissipative material. Examples of how to connect workstations to meet ESD requirements.