All boilers used in generating steam in and about coal mines or in sinking shafts shall be kept in good order. The operator of every coal mine where steam boilers are in use, shall have the boilers thoroughly examined by a competent boilermaker, or other qualified person, not an employee of the operator, as often as once in every 6 months, and oftener if the State Mine Inspector so requires in writing. The result of every such inspection shall be reported on suitable blanks to the State Mine Inspector.