Diesel particulate filters physically trap emission particles in the exhaust. The diesel particulate filter is a porous filter material that combusts particulate matter through a combination of filtration and chemical reactions, similar to an oxidation catalyst. Diesel particulate filters can reduce hydrocarbons (HC), carbon monoxide (CO) and particulate matter (PM) by 90 percent.

Filters can be a costly solution and they must be used in conjunction with ultra low sulfur diesel fuel (ULSD). Before making the choice to use diesel particulate filters, certain requirements (such as fuel availability) will need to be discussed with your customer.