Coal exploitation in Polish mines is conducted under conditions of associated natural hazards such as methane, fire and coal dust explosion hazards. Orogen drainage is one of the main means of self-monitoring of methane hazards. The possibility of orogen drainage has been approached both from the surface and from underground workings with openings. Methane drainage in a Polish coal mine is caused by: former mine workings, dog-hole workings, especially during their sinking, and haulm. Methane drainage is estimated by the methane flux accompanied in drainage processes to the total methane flux from drainage and ventilation.
