Per EN 61340-5-1 Edition 1.0 2007-08 “Table 3 EPA requirements the limit for Working surfaces, storage racks and trolleys is <1x10E9 ohms tested per IEC 61340-2-3” and per NOTE 6 “In situations where charged device model (CDM) damage is a concern a lower point to point resistance limit of 1x10E4 ohms is recommended.”
“The most important functional consideration for work surfaces is the resistance from the top of the surface to the groundable point [Rgp]. This establishes the resistance of the primary path to ground for items placed on the surface. IEC 61340-5-1 has set a resistance to ground range for work surfaces of less than 1,0 x 10E9 ohms.
However, it is sometimes necessary to use work surfaces that are much more conductive. This is allowed under IEC 61340-5-1 but the reasons for using a more conductive work surface shall be documented in the ESD control program plan.” [CLC/TR 61340-5-2:2008 User guide clause 4.7.1.2.5 Electrical considerations – Work Surfaces] |