Through their own movement people can generate large amounts of static charge if they are not grounded. Over 30,000 volts can be carried by people who are completely unaware that they themselves are the potential source of an electrostatic spark discharge that could ignite a flammable atmosphere.
Discharges of static electricity have been identified as an ignition source for a broad range of processes that cut right across a wide selection of industry groups with both plant equipment and personnel based operations.
Static charge accumulation on workers can be prevented by issuing them with footwear that is designed in accordance with EN 20395:2011 and ASTM F2413 (2018) safety standards or recommended practice documents like IEC 60079-32-1 and NFPA 77 that incorporate static dissipative properties in the structure of the footwear.
Static dissipative footwear is designed to prevent hazards that may arise due to excessively high footwear resistance with respect to ground. Regular testing of static dissipative footwear is strongly recommended to ensure the static dissipative properties of the shoes do not change during the duration of their use.
The Earth-Rite® Sole-Mate II tester from Newson Gale, provides a time efficient and cost effective method of ensuring personnel operating in hazardous areas are wearing static dissipative shoes that are capable of preventing electrostatic charge accumulation on their bodies. The system tests the condition and measures the resistance of the footwear to ensure static is capable of dissipating from personnel through their shoes to ground.
The Sole-Mate II testing station is typically located at the entrance to a hazardous area and plant personnel are afforded a quick ‘pass’ or ‘fail’ reading instantly. If the resistance of the shoes is too high, the Sole-Mate II tester will indicate that the shoes have failed the test via a red LED and buzzer alarm. If the shoes pass the test a green LED will indicate to the operator that the shoes are fit for purpose.
For those companies that want to interlock the system to certain areas of their facility with entry access or audible alarms, an integral volt free relay contact makes it possible for the system to prevent access to a hazardous area without a pass reading on the tester, indicating that only suitable footwear is being worn upon entry.