Section 75.212 - Rehabilitation of areas with unsupported roof(a) Before rehabilitating each area where a roof fall has occurred or the roof has been removed by mining machines or by blasting- (1) The mine operator shall establish the clean up and support procedures that will be followed;(2) All persons assigned to perform rehabilitation work shall be instructed in the clean-up and support procedures; and(3) Ineffective, damaged or missing roof support at the edge of the area to be rehabilitated shall be replaced or other equivalent support installed.(b) All persons who perform rehabilitation work shall be experienced in this work or they shall be supervised by a person experienced in rehabilitation work who is designated by the mine operator.(c) Where work is not being performed to rehabilitate an area in active workings where a roof fall has occurred or the roof has been removed by mining machines or by blasting, each entrance to the area shall be supported by at least one row of posts on not more than 5-foot centers, or equally effective support.