- Diseases and injuries
- Equipment, tools, and parts
- Geographic regions
- Geologic conditions and events
- Hazard prevention and control
- Hazards and exposures
- Mine locations, excavations, and structures
- Mining types and methods
- Population groups
- Products and materials
- Research disciplines
- Research methods and measures
- Tasks and activities
- Document types
Results 111 - 113 of 113
1/1/1974 - Reports of InvestigationsThe Bureau of Mines found sulfur hexafluoride (SF6), released from a lecture bottle, to be an ideal gaseous tracer for studying mine ventilation systems. In a Pennsylvania limestone mine, this technique was useful in evaluating the effectiveness of auxi...
1/1/1973 - Reports of InvestigationsSamples of gas were obtained directly from the coalbed during drilling of horizontal and vertical boreholes in six different formations. The samples were analyzed by gas chromatography.
7/1/1972 - Technical Progress ReportsAn oil well penetrating the Pittsburgh bituminous coalbed in northern West Virginia was plugged and safely mined through 3 months later. Effectiveness of the plugging in preventing reservoir gas from entering the mine through the well hole was verified ...