Under federal law, all coal miners must be provided with a self-rescue device that will provide them with at least an hour's worth of breathable air to escape in the event of an underground fire or explosion.
MSHA and NIOSH jointly certify the devices as complying with federal regulations, and the agencies have an agreement through which they are jointly charged with dealing with any problems that come up later when devices are in use.
In 2010, MSHA and NIOSH launched a joint investigation of problems that were eventually traced to the oxygen cylinders used in the initial start-up of the SR-100 devices. Initially, CSE said it had instituted a "recall" of the troubled units, but later conceded it had not actually ordered coal companies to stop using the devices.
Scott Shearer, president of CSE, did not return a phone call Tuesday, but said in a prepared statement that his company has "received no final directive from NIOSH or MSHA regarding the SR-100."
"CSE voluntarily ceased production of the SR-100 when the company's internal quality control process identified a possible issue with the oxygen cylinder," Shearer said in the statement.
"We have remained committed to working with the agencies for some time to resolve any and all concerns," he said. "Once we receive final notification from the regulatory agencies, we will continue to develop appropriate next steps."
In lawsuits after the Sago disaster, families of the miners were investigating concerns that the SR-100 cylinders, made by a vendor for CSE, somehow leaked, leaving the units without enough oxygen to start properly. Those suits were settled, and the terms were kept confidential.
NIOSH said in its new report that an engineering firm hired by CSE had concluded that a loss of oxygen in the starter cylinders occurred at a threaded connection between the cylinder body and oxygen outlet assembly.
"When asked to determine the percentage of affected, assembled, SR-100s, CSE responded that it was less than 1 percent overall," the NIOSH report said.
"CSE could not identify a systemic cause or otherwise confine the failure to within certain lots," the agency report said. "Therefore, the failure could exist among all field-deployed units."
Reach Ken Ward Jr. at kw...@wvgazette.com or 304-348-1702.