(a) Generally. -- The method of mining followed in any coal mine shall not expose the miner to unusual dangers from roof falls.
(b) Roadways, intersections and arches. -- The width of roadways shall not exceed sixteen feet unless additional support is added cross sectional. During the development of intersections, the roof between the tangents of the arches in the entry or room shall be supported with artificial roof supports prior to the development of such intersections. All areas where the arch is broken shall be considered as having unsupported roof and such roof should have artificial roof supports installed prior to any other work being performed in the area.
(c) Examinations and corrections. -- Where miners are exposed to danger from falls of roof, face and ribs, the operator shall examine and test the roof, face and ribs before any work or machine is started, and as frequently thereafter as may be necessary to insure safety. When dangerous conditions are found, they shall be corrected immediately. A probe or probes for methane detectors shall be provided on each working section other than longwall sections and sections mined solely with contininuous miners with integral roof bolters.
(d) Roof bolt recovery. -- Roof bolts shall not be recovered where complete extraction of pillars is attempted, where adjacent to clay veins or at the locations of other irregularities, whether natural or otherwise, that induce abnormal hazards. Where roof bolt recovery is permitted, it shall be conducted only in accordance with methods prescribed in the approved roof control plan, and shall be conducted by experienced miners and only where adequate temporary support is provided.