CFR > Title 30 - Mineral Resources > CHAPTER I—MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR > SUBCHAPTER O—COAL MINE SAFETY AND HEALTH (parts 70 to 90) > PART 75—MANDATORY SAFETY STANDARDS—UNDERGROUND COAL MINES > SUBPART C—Roof Support (§75.200 to §75.223) > 75.205—Installation of roof support using mining machines with integral roof bolters.

75.205—Installation of roof support using mining machines with integral roof bolters.

When roof bolts are installed by a continuous mining machine with intregal roof bolting equipment:
(a) The distance between roof bolts shall not exceed 10 feet crosswise.
(b) Roof bolts to be installed 9 feet or more apart shall be installed with a wooden crossbar at least 3 inches thick and 8 inches wide, or material which provides equivalent support.
(c) Roof bolts to be installed more than 8 feet but less than 9 feet apart shall be installed with a wooden plank at least 2 inches thick and 8 inches wide, or material which provides equivalent support.