Operators of underground coal mines will be required to take far stronger action to prevent explosions like the one that killed 12 men at the Sago Mine last year, under new rules issued by the federal Mine Safety and Health Administration.
The rules, which take effect Tuesday, follow the agency’s conclusion that lightning sparked methane gas in a sealed section of the West Virginia mine.
Mine operators will be required to give up the long-standing practice of sealing and forgetting abandoned sections of underground mines. Companies will now be required to monitor such areas for explosive gases.
Source : http://articles.latimes.com/2007/may/19/nation/na-briefs19.5