The agency, which reviews civil penalty amounts at least once every four years, revised the penalty amounts to fall in line with the nation's inflation rates. The final rule will make regulation amendments effective March 10.

Three penalties were increased in the ruling, the first being an increase in maximum civil penalty from $US60,000 to $70,000. The maximum daily fine for operations also jumped from $6500 to $7500.

Third, the maximum penalty for smoking on a minesite has gone from $275 to $375.

"These penalties were last adjusted, as appropriate, in 2003 based on the CPI of the previous year," MSHA said, adding that the last smoking fine adjustment was in 1998 when the penalty went from $250 to $275. It will apply to the entire mining industry regardless of product.

The average cost of the rules for coal mines is $229,286, with $201,180 of that amount for operations with 1 to 500 workers, according to its report.

"MSHA has concluded that the final rule will not have a significant impact on a substantial number of small entities," it said.