OccupatiOnal and safety shOes

Technical InformationWhen setting up an “EPA area”, the following question shouldalways be asked: how many volts can the component withstand?Because it requires only approximately:3000 Volt, to let man having a disagreeable sensations100 Volt, to delete information from a magnetic datacarrier50 Volt, to generate sparks which can ignite explosivegases30 Volt, to damage electrical components5 Volt, to damage highly sensitive hard-disc readingheads during their production.In many cases discharges cause “latent damage” that manifestas defect or trouble only after a certain period of time or underspecific circumstances.DefinitionESDElectrostatic DischargeElectrostatic discharge is caused by an imbalance of potential oncharged objects or people by contact or close proximity.ESDSElectrostatic Discharge Sensitive DeviceEPAElectrostatic Protected AreaArea where sensitive devices can be handled directly with minimumrisk of electrostatic damage.Electrostatic chargeIs produced by frictional contact and separation of two materials.INFORMATIONFor the daily function testing of the shoes the use of teststations has been established. There the resistance of personand shoe is measured. Attention should be paid to theseparate measuring to the feet.Resistance Terminology10 3 Ohm = 0,001 MOhm = 1 kOhm10 4 Ohm = 0,01 MOhm = 10 kOhm10 5 Ohm = 0,1 MOhm = 100 kOhm10 6 Ohm = 1 MOhm = 1.000 kOhm10 7 Ohm = 10 MOhm10 8 Ohm = 100 MOhm10 9 Ohm = 1.000 MOhm = 1 GOhm10 10 Ohm = 10.000 MOhm = 10 GOhm10 11 Ohm = 100.000 MOhm = 100 GOhm10 12 Ohm = 1.000.000 MOhm = 1.000 GOhmResistance to ground (Rg) EN 61340It is the resistance from a surface or an item within an EPA,measured with a suitable ohmmeter and test probe.Latent damageIt is the damage caused by ESD to sensitive devices, which hasthe effect of reducing components reliability without causingimmediate failure.The symbol has been used since 1984 and denotes componentsand subassemblies that are ESD susceptible.„ESD SUSCEPTIBLE“The symbol was introduced in addition to symbol No. 1 in 1993and denotes ESD protective products such as anti-static mats,trucks, clothing, pro- tective covering, cartons, materials, etc.„ESD PROTECTIVE“ESD - Electrostatic Discharge7