Testing the Quality of Ventilation TubeConnecting the Methane Mines in OperationControl Static Electricity

In underground mines, methane is allowed to use only the ventilation pipes that are made of antistatic materials. In order requirement for electrical conductivity was filled, it is necessary that the surface resistance of ventilation tubes is less than 108 Ω [9]. Ventilation ducts for ventilation of blind facilities in underground mines, are usually long after a few hundred meters, which means that they are composed of multiple tubes, which are usually produced in lengths of 10 m. To a distortion of electrical resistance may arise if the joints between pipes are bad, what would lead to the formation of islands with extensive exposure to static electric charges, which would be threatened with defeat breakdown strength of air of 3 MV/m, because the generation of static electricity due to continuous air flow process. In other this work will be presented to the measurement methods with which to control the quality circuit between the ventilation pipes in real conditions and with the results of measurements. Control and monitoring of static electricity is particularly important in underground methane mines, in order to prevent the occurrence of electrostatic sparks, which could cause an explosion.