The Current European Standard, BS EN 61340-5-1 ‘Protection of Electronic Devices from Electrostatic Phenomena’ is quite categorical, clear and unambiguous when it comes to describing and defining what is required from a floor in an area where ESD sensitive items are present. These floors are commonly, although incorrectly, referred to as anti static floors. A floor which allows the movement of ESD sensitive items within an EPA without additional protection, such as shielding bags, must comply with the following criteria:
The resistance to ground (Rg) of the person/footwear/floor combination must be less than 1 x 109 Ω (1 gigohm) provided any individuals’ body voltage is maintained at less than 100v.
In addition to installing a floor system for appropriate ESD protection of electronic devices, the risk of electrocution is a critical safety factor which can all too easily be overlooked. Electrical hazard reduction practices should be exercised and consideration given to the nature of the work being carried out in areas where an ESD protected floor is installed – a minimum resistance value may be required for safety reasons.
SSE will always recommend that flooring within an EPA is selected to provide safe working conditions at all times. This can most effectively be achieved by choosing a floor which provides a resistance to ground (Rg) that is greater than 1 x 106 Ω (1 megohm).
With an Rg above 1 x 106 Ω and even when low resistance footwear and/or chairs are in use, any electric shock will be limited to a safe level.