The local electrostatic charge of clothes and shoes gradually spreads to the whole surface according to the law of charge dispersion on the medium, and a certain electrostatic voltage is formed on the clothes when it reaches equilibrium. Of course, because the human body itself is a good conductor, charging clothes will make the skin of the human body charged by electrostatic induction, and also form a certain electrostatic voltage. So for operators, there are two possible emission channels; One is the discharge between fingertip (skin) and grounding conductor, and the other is the discharge between work clothes and grounding conductor. Both of these discharges may damage electrostatic sensitive devices. When people are engaged in various activities, the electrostatic voltage on clothes has greatly exceeded the threshold of electrostatic discharge damage of many electrostatic sensitive devices, so touching or approaching these components may cause damage to sensitive devices.
It is generally believed that wearing cotton overalls can prevent electrostatic accumulation of clothes. In fact, this view is one-sided, and it can only be basically realized when the relative humidity of the air is higher than 50%. When the relative humidity is low, the charging capacity of pure cotton products increases obviously. The test shows that when the relative humidity is lower than 30%, the charge of pure cotton fabric is equivalent to that of polyester. When the relative humidity is lower than 20%, the charge of cotton fabric will even be higher than that of some chemical fiber fabrics. Therefore, in dry areas, we can't expect to use pure cotton products to eliminate the electrostatic hazard of clothing under any circumstances. Therefore, in order to effectively prevent the harm of electrostatic discharge of human static electricity, operators must wear anti-static work clothes.