Widely used for draining methane in coal mines in the United States where the
room-and-pillar method is employed. They are panel entries driven on a
perimeter of a block of coal being mined and maintained as exhaust airways to
remove methane promptly from the working faces to prevent buildup of high
concentrations either at the face or in the main intake airways. They are
maintained, after mining is completed, in preference to sealing the completed
workings. Hartman, 1
Source: Dictionary of Mining, Mineral, and Related Terms
Source:
Dictionary of Mining, Mineral, and Related Terms
