If office workers can worry about the health hazards of poor air circulation, imagine how coal miners feel about it. When dust and methane gas accumulate in underground mines, the hazards range from explosions to lung disease. That is why thousands of miners turned out at hearings last week to protest proposed changes in federal rules that they believe would relax their fresh-air safeguards. Among the revisions being considered by the Government's Mine Safety and Health Administration: allowing methane levels in some mines to be monitored by electronic devices instead of human inspectors.
While agency staffers say the changes would bring...