West Virginia's mine safety office warned coal companies Tuesday that some emergency air packs have suffered heat damage and that it cannot say for certain whether thousands of others will work.
After conducting tests and taking a complete inventory of the air packs, the Office of Miners' Health Safety and Training cautioned mining companies to make sure the air packs are not exposed to heat sources such as hydraulic lines and heavy equipment.
Emergency air packs typically provide miners with one hour of clean air in the event of a fire, explosion or other accident. Heat can make rubber parts such as hoses and seals deteriorate and also reduce the devices' ability to generate oxygen.
The testing and inventory were conducted in reaction to the Sago Mine disaster that killed 12 miners in January. Survivor Randal McCloy Jr., who has sued air pack maker CSE Corp., has said four members of his 12-man team could not get their CSE packs to work. Federal testing showed the devices were able to generate oxygen.
On Tuesday, the mine agency instructed mine operators to remove any air packs suspected of exposure to high temperatures.
"I wouldn't think that there would be a high percentage, but I would think that there may be some out there. If you happen to need one and you happen to get one of those that had been exposed, then you would not be in the best situation," mine safety chief Ron Wooten said.
Monroeville, Pa.-based CSE, has about 65 percent of the national market.
The state inventory found that the color-coded sensors that show whether packs have been exposed to high heat were tripped on 63 of CSE's units, and 15 devices made by another manufacturer also showed heat damage.
However, the state has no way of telling if approximately one-fourth of the 10,500 air packs in the state — mostly older models made by CSE — have been exposed to high temperatures, because those devices have no heat indicators on them.
No figures are available for the number of emergency air packs in use nationwide, though federal law requires one for every miner.
Earlier in October, the National Institute for Occupational Safety and Health said its own tests showed that problems with CSE air packs, including damaged air hoses and high levels of carbon dioxide, were getting worse, not better.
CSE President Scott Shearer said he shares the state agency's safety concerns. The mining industry must do more to prevent poor care and handling of air packs.
"It takes the industry to address this," he said.