Explosion hazards from methane emissions related to geologic features in coal mines
By: by James P. Ulery.
Contributors: National Institute for Occupational Safety and Health.; Pittsburgh Research Laboratory (National Institute for Occupational Safety and Health)
Series: DHHS (NIOSH) publication -- no. 2008-123; Information circular -- 9503; DHHS publication -- no. (NIOSH) 2008-123.; Information circular (National Institute for Occupational Safety and Health) -- IC 9503.
Publisher: Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, Pittsburgh Research Laboratory
Published: 2008
Place of publication: Pittsburgh, PA
Language: eng
Number of pages: 18
Subjects: Coalbed methane; Mine gases -- Flammability; Mine gases -- Safety measures; Coal mines and mining -- Dust control; Mine explosions -- Prevention
Description: "Explosions in U.S. coal mines have caused death and injury to miners and destruction of workings since the first reported explosion in 1810. These explosions are caused when buildups of explosive gas and/or dust in the mine are ignited by the presence of a flame or spark. Methane gas is inherently generated and held by adsorption in coal and is normally liberated during mining. Because this gas is explosive in the range of 5%-15% by volume, fresh air is constantly supplied to the working face to prevent the methane/air mixture from reaching this explosive range. The required amount of ventilation air is based on estimates of gas release under normal conditions. Occasionally, unanticipated and unusually high emissions are encountered, which, despite normal ventilation controls, result in an explosive mixture that a spark from a cutting bit or electrical equipment can easily ignite. Investigations have shown that such emissions are often associated with anomalous geologic features or conditions. Although most operators are aware that certain geologic features may adversely affect productivity, few are aware of their potential as a gas emission hazard. This report presents a historical framework detailing the impact of geologic features on excess gas emissions and resultant mine explosions. It also provides operators with specific information on recognizing and alleviating potential hazards from methane emissions related to these geologic features"-- P. [1].
Notes: "April 2008."

Includes bibliographical references (p. 16-18).

Also available via the World Wide Web as an Acrobat .pdf file (798.5 KB, 24 p.).
Table of contents: title: Introduction; title: Gas emissions associated with outbursts, blowers, and feeders; title: Gas emissions associated with geologic features; title: General remediation consideration