(a)
(1) All persons who perform the work of removing permanent roof supports shall be supervised by a management person experienced in removing roof supports.
(2) Only persons with at least one year of underground mining experience shall perform permanent roof support removal work.
(b) Prior to the removal of permanent roof supports, the person supervising roof support removal in accordance with paragraph (a)(1) of this section shall examine the roof conditions in the area where the supports are to be removed and designate each support to be removed.
(c)
(1) Except as provided in paragraph (g) of this section, prior to the removal of permanent supports, a row of temporary supports on no more than 5-foot centers or equivalent support shall be installed across the opening within 4 feet of the supports being removed. Additional supports shall be installed where necessary to assure safe removal.
(2) Prior to the removal of roof bolts, temporary support shall be installed as close as practicable to each roof bolt being removed.
(d) Temporary supports installed in accordance with this section shall not be removed unless -
(1) Removal is done by persons who are in a remote location under supported roof; and
(2) At least two rows of temporary supports, set across the opening on no more than 5-foot centers, are maintained between the miners and the unsupported area.
(e) Each entrance to an area where supports have been removed shall be posted with a readily visible warning or a physical barrier shall be installed to impede travel into the area.
(f) Except as provided in paragraph (g) of this section, permanent support shall not be removed where -
(1) Roof bolt torque or tension measurements or the condition of conventional support indicate excessive loading;
(2) Roof fractures are present;
(3) There is any other indication that the roof is structurally weak; or
(4) Pillar recovery has been conducted.
(g) Permanent supports may be removed provided that:
(1) Removal is done by persons who are in a remote location under supported roof; and
(2) At least two rows of temporary supports, set across the opening on no more than 5-foot centers, are maintained between the miners and the unsupported area.
(h) The provisions of this section do not apply to removal of conventional supports for starting crosscuts and pillar splits or lifts except that prior to the removal of these supports an examination of the roof conditions shall be made.
[55 FR 4595, Feb. 8, 1990]