State & Local Toolkit: Building Support

Protecting Public Health

Older diesel engines emit large amounts of nitrogen oxides (NO_x) and particulate matter (PM). Both of these pollutants contribute to serious public health problems that result in instances of premature mortality, asthma attacks, lost work days, and numerous other health effects. In addition, children, the elderly, and people with existing heart or lung disease, asthma, or other respiratory problems are especially sensitive to the health effects of fine particles. EPA has also determined that diesel exhaust is a likely human carcinogen.

For more information:

• EPA's Health Assessment for Diesel Exhaust
• Particle Pollution and Your Health (PDF) (2 pp, 320K) identifies who is at risk from exposure to particle pollution, what health effects may be experienced, and simple actions to reduce the risk.
• The Air Quality Index (AQI) measures and reports daily the quality of outdoor air throughout the nation and the associated health risks.

top of page

Air Quality Goals and Mitigation Measures

Diesel engines can affect an area’s efforts to meet National Ambient Air Quality Standards. Clean diesel strategies are cost-effective. The emission reductions they produce can help satisfy State Implementation Plans (SIPs) and conformity plans. Clean diesel strategies can also be used as mitigation measures under programs such as the National Environmental Policy Act (NEPA) and the Supplemental Environmental Project (SEP).

Claiming SIP Emissions Credit

Diesel retrofit technologies reduce pollution from the existing diesel engine fleet by up to 90 percent for PM, up to 50 percent for NO_x, and up to 90 percent for volatile organic compounds.

• Diesel Retrofits: Quantifying and Using Their Benefits in SIPs and Conformity (PDF): Guidance for State and Local Air and Transportation Agencies (69 pp, 531K, EPA420-B-06-005, June 2006)
• EPA’s Diesel Retrofit SIP and Conformity Guidance (PDF) (7 pp, 195K, EPA420-F-06-034, June 2006) summarizes key points of the SIP and conformity retrofit guidance.
• Guidance for Quantifying and Using Long Duration Truck Idling Emission Reductions in State Implementation Plans and Transportation Conformity (PDF) (33 pp, 379K, EPA420-B-04-001, January 2004) provides information about reducing emissions from trucks.
• SmartWay SIP and Conformity Guidance (PDF) (35 pp, 306K, EPA420-B-07-004, June 2007) describes how to quantify and use reductions in nitrogen oxides (NO_x).
• Truck Guidance Fact Sheet (PDF) (3 pp, 106K, EPA420-F-07-045, June 2007)
• Guidance for Quantifying and Using Long Duration Switch Yard Locomotive Idling Emission Reductions in State Implementation Plans (PDF) (25 pp, 343K, EPA420-B-04-002, January 2004) provides information about reducing emissions from locomotives.

Cost Effectiveness Information

• The Cost-Effectiveness of Heavy-Duty Diesel Retrofits and Other Mobile Source Emission Reduction Projects and Programs (PDF) (17 pp, 956K, EPA-420-B-07-006, May 2007)
• Diesel Retrofit Technology: An Analysis of the Cost Effectiveness of Reducing Particulate Matter and Nitrogen Oxides Emissions from Heavy-Duty Nonroad Diesel Engines Through Retrofits (PDF) (22 pp, 411K, EPA420-R-07-005, May 2007)
• Diesel Retrofit Technology: An Analysis of the Cost Effectiveness of Reducing Particulate Matter Emissions from Heavy-Duty Diesel Engines Through Retrofits (PDF) (37 pp, 1.3MB, EPA420-S-06-002, March 2006)

Clean Diesel Collaboratives

Reducing diesel emissions is a shared responsibility. Collaboration has been the hallmark of successful clean diesel programs. A successful program brings together the right people from government, environmental and community organizations, fleet owners/operators, private industry, and other stakeholders.

As part of the National Clean Diesel Campaign, seven regional collaboratives across the nation work to leverage funds and take a local approach to diesel emission mitigation. These Clean Diesel Collaboratives are diverse, multi-stakeholder groups that provide technical assistance, foster partnerships, and identify and leverage resources.

Regional Clean Diesel Collaboratives

• Northeast Diesel Collaborative (EPA Regions 1, 2)
• Mid-Atlantic Diesel Collaborative (EPA Region 3)
• Southeast Diesel Collaborative (EPA Region 4)
• Midwest Clean Diesel Initiative (EPA Region 5)
• Blue Skyways Collaborative (EPA Regions 6, 7)
• Rocky Mountain Clean Diesel Collaborative (EPA Region 8)
• West Coast Collaborative (EPA Regions 9, 10, with Canada and Mexico)

top of page

Outreach and Education Materials

Examples of state and local government outreach and education programs to reduce diesel emissions:

• Alaska's Retrofit Projects outlines retrofit technologies available and summarizes future, ongoing, and successfully completed projects.
• DieselWise Indiana provides information on the Indiana Department of Environmental Management's diesel emissions reduction efforts, including projects that retrofit and/or reduce idling from vehicles. The state also awarded a State Quantity Purchase Agreement (QPA) for state governments to purchase diesel oxidation catalysts (DOCs).
• Greater Boston Breathes Better (GB3) is a partnership among public, private, and governmental entities to help greater Boston's citizens and visitors to breathe better. GB3 promotes strategies and implements projects to reduce air pollution from transportation and construction sources.
• New York Metropolitan Transportation Council (NYMTC) is using more than $100 million in Congestion Mitigation and Air Quality (CMAQ) funds on clean diesel projects. Projects can be found in the NYMTC's Transportation Improvement Program.
• Philadelphia Diesel Difference (PDD) is a coalition of diverse partners with a mutual interest in reducing air pollution from diesel engines in the greater Philadelphia area.
• Wisconsin Partners for Clean Air program is retrofitting more than 500 school buses with a grant from EPA and the Wisconsin Department of Transportation.

Additional outreach and educational materials to:

• National Clean Diesel Campaign’s Publications
• Clean School Bus USA Outreach Materials
• Clean Ports USA Publications
• Clean Construction USA Publications
• SmartWay Transport Partnership Publications
• EPA State and Local Transportation Resources