The Mine Safety and Health Administration (MSHA) alerted the mining community Dec. 10 to possible problems with certain self-contained self-rescue (SCSR) breathing units required in underground coal mines.
MSHA said it has found eight CSE self-rescue units manufactured from 1991 through 1993 to have "deteriorated hoses."
"We're moving rapidly to determine the extent of the problem," said David McAteer, assistant secretary of labor for mine safety and health. "MSHA is working cooperatively with all parties, including the manufacturer, industry and labor organizations and the National Institute for Occupational Safety and Health."
MSHA began its investigation into the CSE units after a miner opened a SCSR unit during a recent fire and discovered a deteriorated breathing hose.
Immediately, tests began on 242 similar units and seven more deteriorated hoses were found.
McAteer said that tests so far had not determined the cause of the deteriorated hoses.
Possible factors may include exposure to heat, age or type of material used for the hose. All units so far found to have problems were manufactured before 1994.
Visual inspections generally do not reveal any hose problems. The agency emphasized that mine operators should perform regular, thorough inspections of their SCSR units and remove from service any units with detectable damage.
Federal mining regulations require that all underground coal miners be supplied with a breathing device that will provide at least one hour of oxygen in a mine emergency such as a fire or explosion.
For more information, go to the MSHA Web Site at www.msha.gov