Trapping of Lead Particulates in Automotive Exhaust

Systems for controlling automotive exhaust particulates, especially lead particulates, are discussed and a suitable method for determining automotive particulate emission levels during on-the-road vehicle operation is presented. Data is presented for a large number of vehicles. The evaluation system is suited for use with a large variety of vehicles during all modes of vehicle operation. A total emissions control system, capable of meeting the strict 1978 statutory gaseous emissions levels with virtually zero particulate emissions, is also discussed. This emissions control system is compatible with leaded and unleaded fuels. The economic implications of lead additive restriction, as a means of reducing lead airborne particulates, are briefly considered. It is concluded that the reduction of airborne lead, by trapping it in the exhaust system, is more cost effective and energy conservative than is reduction by regulation of the fuel supply. Particulate traps coupled with lead-tolerant emission control systems allow this alternative.