5 July 2001
The US Mine Safety and Health Administration (MSHA) has finalized its diesel emission rule for metal/non-metal underground mines (i.e., non-coal mines). The final rule, published on 19 January 2001 and delayed on 15 March 2001 and on 21 May 2001, will become effective 5 July 2001.
Some provisions of the rule concerning tagging of equipment for maintenance purposes have been delayed. MSHA has published a separate proposal outlining the details on the delayed provisions and requesting comments from the mining community.
The non-coal mine rule introduces threshold limit values (TLV) for ambient concentrations of diesel particulates. To meet an interim exposure limit of 400 µg/m3 (measured as total carbon, effective 18 months from 5 July 2001), MSHA estimates mines in the US will have to retrofit 3058 engines with particulate filters. To meet the final limit of 160 µg/m3 (5 years), additional 776 engines will have to be retrofitted.