Mobile Source Controls: Diesel Engine Retrofits

Diesel engine retrofits, which either replace engines or install effective emission controls on older diesel engines (especially those built before 2007), can attain a great reduction in PM emissions. Retrofits can be used on trucks, school buses, construction vehicles (e.g. dump trucks and cranes), diesel-powered equipment (e.g. generators and pumps), ships and trains.  Retrofits would particularly benefit the many residents living near busy roads, children riding school buses (70% of DPS’s bus fleet is diesel (1)), and truck drivers.  To date, 30% of Detroit Public School buses have been converted from diesel to propane-gas.  Also, Southwest Detroit Environmental Vision has led a retrofitting program with funding from MDEQ, Michigan Department of Transportation, U.S. Environmental Protection Agency, and local business partners.  Additional retrofit strategies include:  passing laws and ordinances at State and local levels to require pollution control devices; requiring low-emission vehicles and construction equipment in city contracts; and including low-pollution construction equipment language in Community Benefits Agreements.

1. Crain’s Detroit Business. 2015. Detroit students to ride to school on propane-fueled buses. Available: [accessed 3 February 2016].

Contact CAPHE

Alison Walding
Project Manager
Community Action to Promote Healthy Environments

University of Michigan School of Public Health
1415 Washington Heights
Ann Arbor, MI 48109-2029