Ordinance of the Czech Mining Authority amending Decree of the Czech Mining Authority No. 340 / 1992 Coll., on requirements for qualification and competence and on verification of professional competence of workers for mining and mining activities and amending certain regulations issued by the Czech Mining Authority to ensure safety and health at work and safety of operations in mining and mining activities, as amended by Decree No. 239 / 1998 Coll.