Anti-static equipment (product) and anti-static work area
1. Definition of Anti-static Work Area (EPA)
Equipped with a variety of anti-static equipment and equipment, can limit the electrostatic potential, with definite boundaries and special markings suitable for electrostatic protection operations are called anti-static work areas.
All operating procedures or the production of electrostatic discharge sensitive electronic products (components) should be regarded as anti-static work areas. In this area, both hardware and software management should meet the requirements of the aforementioned anti-static system. At the same time, the allowable electrostatic potential value to the ground (grounding) in any designated space in the work area does not exceed ±100 volts (level A), or does not exceed ±1000 volts (level B).
2. Anti-static equipment (supplies)
⒈Anti-static work clothes
Anti-static work clothes are made of a blend of conductive fibers and cotton, and they are also made of carburized or conductive synthetic fiber Viennese cloth. When rubbing, the generated static electricity leaks through the contact between the conductive fibers and the human body or through the corona discharge between the conductive fibers, and is dissipated. This prevents static electricity from accumulating.
Pay attention to the following points when using anti-static work clothes:
Generally, non-antistatic woven special lining is not used. When it must be used, the lining used shall not exceed 20% of the total lining area. Operators are not allowed to wear or take off clothing when in the anti-static work area.
No metal accessories should be used in the whole garment. When it must be used, it should not be exposed directly to the surface of the clothing to avoid metal discharge. You must wear anti-static clothing before entering the anti-static work area.
The structure of the anti-static overalls should be "three-tight" and the abrasion resistance is good and dust-proof.
When wearing work clothes, it must be used with anti-static shoes, and re-examined according to national standards every other year. When the charged electricity exceeds the specified value, it must not be used.
Pure cotton clothing is not suitable for anti-static work clothes when the relative humidity is lower than 40%, because it cannot prevent static electricity from accumulating on it;
⒉Anti-static shoes (conductive shoes)
The sole of the shoe is made of synthetic rubber (rubber and plastic) with conductive material to leak the electrostatic charge carried by the ESDS device operator to the ground and prevent the human body from accumulating static electricity.
The national standard GB4386-95 "Safety Technical Conditions for Anti-static Rubber-soled Shoes and Conductive Rubber Shoes" stipulates that the resistance value of anti-static shoe soles is 1*10 from 5 ohms to 10 ohms, and the resistance of conductive shoes is not more than 1*10 5 ohms. . The difference in use between anti-static shoes and conductive shoes is that anti-static shoes can be used in an environment with electrical equipment and can prevent electric shocks to the human body from 220 voltages. Conductive shoes cannot be used in environments where there is a risk of electric shock.
In order to ensure the elimination of human body static electricity, the resistance value between the sole and the ground should not be greater than 1*10 9 ohms and 1*10 5 ohms respectively.
During the wearing process, no insulation should be attached to the bottom of the shoes, and it is forbidden to wear insulating socks.
Operators must wear anti-static shoes when working in an anti-static work area.