Antistatic & ESD Footwear

According to EN 20345: 2011, a shoe or boot is considered to be antistatic if its’ measured electrical contact resistance falls between 100 kΩ (105 ohms) and 1 GΩ (109 ohms). With a lower resistance, a shoe or boot is considered to be conductive and at higher values, to be insulating. This 100kΩ to 1GΩ range is regarded a sensible compromise, giving protection from electrostatic build up and protection from electrical shocks at lower voltages.

For some industries the risk of uncontrolled electrical discharge (sparks) in potentially explosive atmospheres or the protection of sensitive electronic components and devices are also important considerations. In these situations, another standard for Electro-Static Discharge (ESD) control applies: EN 61340-5-1 (“Electrostatics. Protection of electronic devices against electrostatic phenomena”). 

For ESD footwear the lower limit of electrical resistance is 100 kΩ (the same as for antistatic footwear) and the upper limit is 35 MΩ (3.5 x 107 ohms). This means that a boot that is ESD-capable is by definition also antistatic at the same time. Conversely, not every antistatic boot is ESD-capable e.g. If an electrical resistivity of 100 MΩ is measured, the shoe is antistatic but outside the ESD limits. If the shoe has an electrical resistance of only 1 MΩ, it is both antistatic and ESD-capable.

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Workmaster™ ESD Footwear displays this symbol

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