Refiners should have no problem producing nearly sulfur-free diesel by 2006, according to a report released yesterday by an advisory panel to the U.S. EPA. The panel was convened last year by EPA Administrator Christie Whitman to assess possible technological barriers to complying with a clean diesel rule issued in the final weeks of the Clinton administration. That rule requires refineries to reduce sulfur emissions from 500 parts per million to 15 ppm by 2006, a move that will go a long way toward cleaning up tailpipe exhaust from trucks and buses. Such exhaust causes and accelerates respiratory ailments such as asthma, resulting in thousands of premature deaths per year. Big oil has resisted the 15 ppm rule in the past, saying it might cause distribution problems and fuel shortages. But now the American Petroleum Institute, the large oil companies’ trade group, says the industry will not seek to postpone the diesel rule.