Seals are dam-like structures constructed in underground coal mines throughout the U.S. to isolate abandoned mining panels or groups of panels from the active workings. Historically, mining regulations required seals to withstand a 140 kPa (20 psi) explosion pressure; however, the 2006 MINER Act requires MSHA to increase this design standard by the end of 2007. This report provides a sound scientific and engineering justification to recommend a three-tiered explosion pressure design criteria for new seals in coal mines in response to the MINER Act. Much of the information contained in this report also applies to existing seals.

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