NIOSH/MSHA Tests Identify Strongest Ventilation Stoppings
NIOSH has posted several useful documents in the What's New section of its Web site in recent days, including an "Explosion Effects on Mine Ventilation Stoppings" report dated November 2008 that explains the results of NIOSH/MSHA tests on the strength of mine ventilation stoppings. The research evaluated explosive blast effects on stoppings made of dry-stacked solid and hollow-core concrete block, steel, wet-laid solid concrete block, and an innovative Australian woven cloth. The tests took place at the Pittsburgh Research Laboratory's Lake Lynn Experimental Mine.
The dry-stacked and coated solid-concrete-block performed well, surviving a total explosion pressure of about 6.7 psi (46 kPa) and being destroyed at a total explosion pressure of about 7.6 psi (52 kPa). A steel panel failed at a total explosion pressure of 1.3 psi (9 kPa). An 8-inch-thick wet-laid solid concrete-block stopping coated on one side withstood the strongest pressure, about 26 psi (180 kPa), and was not tested to failure. The woven cloth survived an explosion pressure of 4.0 psi (27 kPa) and was destroyed at about 6.1 psi (42 kPa). The results will help investigators determine the approximate explosion forces that destroy or damage stoppings in actual coal mine explosions.
Other documents made available by NIOSH include a guidelines document for state's public health activities in occupational safety and health, an analysis of the use of Major Hazard Risk Assessment to prevent multiple-fatality events in the U.S. minerals industry, and a report on ways to reduce low-back pain and disability among miners.