Released by the Mine Safety and Health Administration on Friday, the new rule published in the Federal Register goes beyond requirements outlined in the MINER Act and will replace the Emergency Temporary Standard (ETS) that went into effect last May.
The MINER Act states mine seals must be stronger than the 20psi explosive pressure – a minimum established in 1992.
“Under the new rule, operators must strengthen the design, construction, maintenance and repair of seals, as well as sample and control atmospheres behind certain seals. Seal strength must be designed to at least 50psi," MSHA acting assistant secretary Richard Stickler said.
The rule will require air sampling behind seals that are less than 120psi and withdrawal of miners when a dangerous condition is discovered, and the removal of potential ignition sources from sealed areas.
The new rule has the same three-tiered approach as the ETS, which requires additional seal strength where sealed atmospheres are more dangerous.
A certified supervisor for construction and repair of seals with senior management of the mine operator is required to certify seal compliance with the MSHA-approved ventilation plan.
The rule also spells out increased training for those involved in seal sampling and construction; requirements for design certification of seals; and enhanced record keeping to ensure compliance.
While the rule becomes effective immediately, seal manufacturers and mine operators do have six months to submit revised seal applications and ventilation plans.
