In 2010, MSHA proposed a rule that would cut the overall limit for dust in half and require companies to use continuous personal dust monitors, which would provide real-time measurements. The current pumps have to be sent to a lab, where analysis can take weeks.
But the rule would leave much of the sampling in the hands of the coal companies themselves. Asked why, Main said, "It's an enormous task for the government to take on."
Even industry favors MSHA's taking charge of sampling. "We need to get to a point where we remove this cloud of controversy and instill in the minds of everyone that the samples are accurate," the National Mining Association's Watzman said.
'I never said nothing'
Convincing a miner to go to a clinic, get an X-ray or file a claim for benefits can be a challenge. "They're not going to come and complain about how they feel just because that's part of our culture," said Debbie Wills, sitting in the clinic in Cedar Grove, W.Va., where she helps miners get evaluated and file for black lung benefits.
Many miners don't want their employers to know they have signs of the disease -- or even that they've been X-rayed. Anita Wolfe, who runs NIOSH's surveillance program and is often out with the RV that screens miners, said she has seen men approaching on foot from miles away because they didn't want anyone to see their cars parked nearby.
Sometimes miners avoid screening because they just don't want to know. A diagnosis of black lung would likely mean having to leave the mines -- the best-paying job around and the only way they know to provide for their families.
Donald Marcum's brother, James, took a summer job at a mine to earn money for college. "I started earning them $800-a-week paydays and said, 'Why would I want to go to college when I'm earning this kind of money?'" he recalled.
James Marcum, 50, spent much of his 20-year mining career running a continuous miner. In 1991, the motor of the machine he was running caught fire, and smoke overcame him. When doctors examined him and took X-rays, they found what appeared to black lung.
He kept the news to himself and didn't file for benefits, afraid he'd lose his job if he did. "I never said nothing," said Marcum, whose disease has since been confirmed and who is deteriorating rapidly. "I just went on and done my job."
About this project
Our stories about black lung were jointly reported by the Center for Public Integrity and NPR News as part of "Hard Labor," an occasional series on health, safety and economic threats to U.S. workers. Additional reporting was provided by Charleston Gazette staff writer Ken Ward Jr.
Read on the CPI website, http://www.iwatchnews.org/.
Hear more about black lung this afternoon on NPR's All Things Considered and Tuesday on NPR's Morning Edition. Additional NPR stories are available at www.npr.org.