MSHA More Than Doubles Strength Requirements for Alternative Seals to Better Protect Miners Seals in Underground Coal Mines Must Withstand 50 psig Pressure
WASHINGTON—The U.S. Mine Safety and Health Administration (MSHA) is requiring all alternative seals constructed in underground coal mines to withstand 50 pounds per square inch, gauge (psig).
“Information from recent mine accident investigations and technical reviews have led us to dramatically raise the strength requirements for alternative seals, to better protect miners from explosions behind sealed areas of underground coal mines,” said David G. Dye, Acting Administrator of MSHA.
Preliminary information indicates that alternative seal failure may have contributed to the deaths of miners at Sago Mine in West Virginia and Darby Mine No. 1 in Kentucky. Preliminary data gathered by MSHA inspectors nationwide suggest that there are problems with the construction of some alternative seals in use in underground coal mines.
The Program Information Bulletin MSHA published today requires:
All new alternative seals be designed and built to reliably withstand an overpressure of at least 50 psig;
Designs of alternative seals and supporting data must be certified by a professional engineer and construction is certified by a senior mine management official; and,
Mine operators and MSHA will examine existing alternative seals to determine whether additional measures are necessary to protect miners.
Mine operators should submit revised ventilation plans to the appropriate MSHA district manager by Sept. 1. Alternative seals were previously required to withstand 20 psig pressures.
