A. Substantially constructed line brattice shall be used from the last open crosscut of an entry or room when necessary to provide adequate ventilation for the miners and to remove gases. Any line brattice that is damaged by a fall or otherwise shall be repaired promptly.
B. The space between the line brattice and the rib shall be large enough to permit the flow of a sufficient volume of air to keep the working face clear of flammable and noxious gases.
C. Brattice cloth that is used underground shall be of flame-resistant material.
D. An accumulation of methane shall be moved only by means of properly installed line brattice or other approved method.