Failures of Fittings and Valves in Refuge Alternatives
The attached PowerPoint® (PPT) presentation, from a June 27, 2012 MSHA meeting, addresses issues related to brass fitting failures in refuge alternatives and 30 CFR, part 7 approval requirements for refuge alternatives in underground coal mines. The presentation summarizes the history of known failures, the order by the West Virginia Office of Miners Health Safety and Training (WVOMHST), the status of examinations performed, and MSHA's alerts and Program Policy Letter. The PPT summary includes a recommendation by WVOMHST and MSHA for additional examinations using a new protocol, retraining examination personnel and providing proper examination tools.
— Powerpoint Presentation
• Powerpoint Version
• PDF Version
Other Resources
Program Policy Letter PPL P11-V-17 The purpose of this PPL is to provide guidance to the mining industry, enforcement personnel, and other parties concerning methods for maintaining approvals on refuge alternatives given the premature failures of brass valves and fittings on breathable air components of refuge alternatives and their impact on MSHA approved Emergency Response Plans (ERPs).Catastrophic Failure Of An Oxygen Cylinder Fitting In A Refuge Alternative On Sunday, January 9, 2011, a catastrophic failure occurred in an oxygen cylinder fitting connected to the breathable air system in a refuge alternative located in an underground coal mine. The refuge alternative was an inflatable tent design manufactured by the A.L. Lee Corporation, model number 4042-35 manufactured on March 21, 2008. This refuge alternative is equipped with 12 high pressure oxygen cylinders, each pressurized at 4,500 psi. The manufacturer of the failed high pressure fitting is unknown at this time. Once the fitting manufacturer is identified, this alert will be updated with this information.
Update on Failure of High Pressure Gas Fittings and Valves in Refuge Alternatives On January 21, 2011, A. L. Lee reported a second CGA 701 brass fitting failure in a refuge alternative that had been returned to their shop. This fitting met the dimensional specifications of the CGA standard. On February 3, 2011, A. L. Lee reported that cracks had been discovered in both the brass fittings and cylinder valves of a third refuge alternative that had been returned to their shop. These fittings also met the dimensional specifications of the CGA standard. These fitting failures are significant because they demonstrate that the problem extends beyond dimensionally incorrect fittings.
Second Update on Failure of High Pressure Gas Fittings and Valves in Refuge Alternatives An Equipment Alert and an update have been issued regarding valve and fitting failures on breathable air components of refuge alternatives. On Sunday, January 9, 2011, a catastrophic failure occurred in an oxygen cylinder fitting connected to the breathable air system in a refuge alternative located in an underground coal mine. On January 21, 2011, A. L. Lee reported a second CGA 701 brass fitting failure in a refuge alternative that had been returned to their shop.