On November 18 at the Charleston Marriot Town Center, the agency will meet with the public and hear input on its ETS regarding the maintenance of incombustible content of rock dust. The gathering will begin at 9am local time and adjourn no later than 5pm.

The agency’s ETS was initially published in the Federal Register on September 23. It is based on a review of accident investigation reports of mine explosions that occurred in intake air courses and involved coal dust.

The standard is also based on the National Institute for Occupational Safety and Health’s report, Recommendations for a New Rock Dusting Standard to Prevent Coal Dust Explosions in Intake Airways.

The emergency temporary standard became effective on the date published in the Federal Register, and applies only to bituminous coal operations.

MSHA also issued a public information bulletin to provide guidance to operators on methods for compliance to the new standard.

Under the standard, the total incombustible content of combined coal dust, rock dust and other dust must be increased from 65% to 80% in all accessible areas of underground bituminous mines, and be at least 65% in other areas.

It also mandates an increase in TIC percentage in all areas underground where methane is present in any ventilating current.

The 80% TIC must be upped by 0.4% for each 0.1% methane in returns, while the 65% TIC in all other areas must be increased by 1% for each 0.1% methane present.

Though the new emergency temporary standard is already effective, MSHA is allowing additional time for mines to purchase more rock dust-related equipment and materials, and is ordering all operators to comply with the new standard by October 7 in newly mined areas, and November 22 elsewhere.

In order to meet compliance deadlines, federal officials are urging operations to begin rock dusting immediately.

All mines should place priority on areas that pose the greatest risk to miner safety, such as near active faces, and in areas where possible ignition sources could be found, including conveyor belt drives and belt entries.