The lawsuit criticises the United States Mine Safety and Health Administration for not including those improvements in its temporary emergency standards issued in response to the spate of fatal coal mine disasters this year.

The move comes a day after Congress passed legislation overhauling mine safety rules.

UMWA backed the legislation but said the lawsuit deals with separate concerns.

UMWA president Cecil Roberts said the union wants MSHA to conduct random checks of oxygen devices used underground because of reports the devices are often faulty.

He said training is typically done in a classroom but should be moved to a mine-like setting.

"MSHA's response has been to call for more study, more recommendations' for coal companies to perhaps consider when it comes to SCSRs," Roberts said.

"We are way past the study and recommendation stages now. Coal miners are dying. We must find out why this is happening and find out now. And then we must make the companies implement needed changes - right now."

But MSHA say the lawsuit is a public stunt that will take away limited rescue resources from miners without making them safer. MSHA’s emergency temporary standard issued in March requires quarterly training in the donning and transferring of SCSRs.

The lawsuit acknowledges that MSHA requires training with SCSRs, but says the training is not realistic or performed as a simulated mine emergency.

UMWA said until the random checks and enhanced training are in place there is substantial potential that more miners will die due to faulty SCSRs, or the miners' inadequate training on the use of SCSRs.