Clean Diesel Technologies Inc., a cleantech emissions control company, says it has received an expanded verification from the Environmental Protection Agency (EPA) for its ECS-branded Purifilter Plus diesel particulate filter (DPF) emission reduction system.

According to the company, Purifilter Plus, featuring Clean Diesel's proprietary MPC catalyst technology, is the only hybrid DPF system employing both passive and active regeneration that the EPA has verified for use in its engine-retrofit programs.

With this expanded verification, Purifilter Plus is now approved for the retrofitting of a vast majority of 1994 to 2010 on-road vehicle exhaust gas recirculation (EGR) and non-EGR engines, the company adds. These vehicles may include school, shuttle and urban buses; municipal, state and utility fleet vehicles; and refuse trucks and urban delivery vehicles.