All examinations held by the Mining Board shall be of a practical nature so as to determine the competency and qualification of the applicant to engage in mining. The Mining Board shall examine under oath all persons who apply for certificates as to their previous experience as miners and shall grant certificates of competency to such applicants as are qualified, which certificates shall entitle the holder thereof to be employed as and to do the work of miners in this State.
225 ILCS 705/8.08