ANTISTATICKÉ VLASTNOSTI A OCHRANA PŘED ELEKTROSTATICKÝM VÝBOJEM
All safety shoes in Blåkläder's assortment are antistatic, which is a basic requirement EN ISO 20345. We also offer models that are verified as ESD products ie. approved for use in EPA areas (Electrostatic Protected Areas).
It’s the electrostatic discharges that needs to be avoided, whether for the antistatic or ESD properties. But there is an important difference; the antistatic specification in EN ISO 20345 is designed to protect the person in the shoes while the requirements of the ESD standards (EN 61340-X-X) are designed to protect the product being handled by the person in the shoes.
The test methods for the two properties differ.
The antistatic characteristics of EN ISO 20345 are evaluated solely on the basis of the shoe and laboratory equipment itself. The contact resistance in the shoe must not exceed 1 GΩ, but also not lower than 100 kΩ. If the shoe is too conductive, it may pose a safety risk for the person wearing the shoe.
The ESD properties can be evaluated using two different methods;
EN 61340-4-3, is a test performed with laboratory equipment and in three levels of humidity, of which class 1 is driest and thus the highest class. The contact resistance must be between 100 kΩ and 100 MΩ to be approved.
EN 61340-5-1, is a test that validate an entire system including shoes and person. If the measured contact resistance is less than 35 MΩ, the shoes are ESD compatible. No lower resistance limit is defined.
This means that even if the test methods differ slightly, a shoe that fulfil the antistatic requirements of EN ISO 20345 may also meet the requirements for being ESD-approved. However, Blåkläder always tests protective shoes separately for the ESD requirements if the model is intended to be approved for use in EPA areas.
Blåkläder's ESD-approved safety shoes are approved by RISE, Research Institutes of Sweden;