Why do downhole workers wear antistatic clothing
The occurrence of gas explosion must meet three basic conditions at the same time, namely:
(1) the gas concentrations in the explosion limit, general ^ 5% - 16%.
(2) the oxygen concentration in the mixed gas should not be less than 12%.
(3) sufficient energy ignition source.
From the three conditions of gas explosion, the concentration of oxygen in the underground can always meet the conditions, and the other two conditions are caused by a variety of reasons, the general prerequisite for controlling gas explosion in the mine is to control the concentration of gas, and at the same time to avoid any ignition source.
There are many ignition sources that can cause gas explosion, including open flame, hot surface and hot gas, mechanical friction, impact spark and electric spark. Electric spark mainly includes arc discharge, electric spark and spark generated by static electricity.
The minimum ignition energy of gas explosion is 0.28mj, while the electrostatic potential of chemical fiber clothing can reach 15kV, and the discharge energy can reach 22.5mj, greatly exceeding the minimum ignition energy of gas explosion. The electrostatic discharge (esd) caused by the chemical fiber clothing often becomes the most important source of gas explosion. Therefore, the electric spark generated by the static electricity of the shoes, boots and clothes of underground workers cannot be ignored. Therefore, it is necessary to wear anti-static clothing.