Diesel Particulate Matter Exposure of Underground Metal and Nonmetal Miners

This final rule revises the May 20, 2006 effective date of the diesel particulate matter (DPM) final concentration limit of 160 micrograms of total carbon (TC) per cubic meter of air (160<INF>TC</INF> [mu]g/m<SUP>3</SUP>) promulgated in the 2001 final rule "Diesel Particulate Matter Exposure of Underground Metal and Nonmetal Miners," and published in the Federal Register on January 19, 2001 (66 FR 5706) and amended on September 19, 2005 (70 FR 55019). This final rule increases flexibility of compliance for mine operators by allowing staggered effective dates for implementation of the final DPM limit, phased-in over a two-year period, primarily based on feasibility issues which have surfaced since promulgation of the 2001 final rule. Furthermore this final rule establishes requirements for medical evaluation of miners required to wear respiratory protection and transfer of miners who are medically unable to wear a respirator; deletes the existing provision that restricts newer mines from applying for an extension of time in which to meet the final concentration limit; addresses technological and economic feasibility issues, and the costs and benefits of this rule.