Transportation-Related Documents
Topic-specific guidance documents that outline EPA policies for crediting programs (e.g., commuter programs, heavy duty retrofit, and fuels) that can help reduce transportation-related air pollution and emissions.
- Accelerated Retirement of Vehicles
- Airports
- Commuter Programs
- Fuels
- Idling
- Intelligent Transportation Systems Management
- Land Use
- Retrofits
- Transportation Control Measures
- Transportation Pricing
Accelerated Retirement of Vehicles
- Guidance for the Implementation of Accelerated Retirement of Vehicles Programs (PDF) (69KB)
Guidance that illustrates a methodology for calculating benefits and an administrative framework targeting vehicles that have been identified as high emitters.
Airports
- Guidance on Airport Emissions and Emission Reductions
These documents and links provide guidance for establishing strategies to reduce airport emissions, including emissions from airport ground support equipment (GSE) and ground access vehicles. These documents were developed for regional, state, and local agencies, airports, airlines, and other organizations that want to reduce airport pollution.- Guidance on Airport Emission Reductions Credits for Early Measures through Voluntary Airport Low Emission Programs (PDF) (312KB)
Joint guidance issued by EPA and the Federal Aviation Administration (FAA) outlining the process for crediting voluntary airport emission reductions in a State Implementation Plan (SIP). - Emissions and Dispersion Modeling System (EDMS)
An FAA air quality assessment tool designed to assess the air quality impacts of airport emission sources, including aircraft, GSE, ground access vehicles, and other sources. - Technical Support for the Development of Airport Ground Support Equipment Reductions (PDF) (734KB)
A study that discusses program design and the potential for achieving emission reductions from GSE. - Airport GSE Model (Excel, 492KB)
A spreadsheet tool that provides users with a quick analysis of the emission benefits and cost-effectiveness of controlling GSE emissions. - Airport GSE Model Directions (PDF) (107KB)
Directions for operating the Airport GSE Model.
- Guidance on Airport Emission Reductions Credits for Early Measures through Voluntary Airport Low Emission Programs (PDF) (312KB)
Commuter Programs
- Guidance on Emissions and Emission Reductions from Commuter Programs
The documents and links below provide guidance for crediting emission reductions from commuter programs, such as EPA's Best Workplaces for Commuters, when the program successfully reduces pollution from vehicle sources.- Guidance for Quantifying and Using Emission Reductions from Best Workplaces for Commuter Programs in State Implementation Plans and Transportation Conformity Determinations (2.2MB, EPA-420-B-07-015, October, 2007)
Guidance describing how to credit commuter benefit programs, such as EPA's Best Workplaces for Commuters program, in a SIP or transportation conformity determination. - Fact Sheet on Guidance for Quantifying and Using Emission Reductions from Best Workplaces for Commuters programs in State Implementation Plans and Transportation Conformity Determinations (also available as a PDF file 3 pp,100KB, EPA-420-F-07-064, October, 2007)
Summary of EPA guidance for state and local agencies that want to credit emission reductions resulting from changes in commuter trip behavior to their SIPs and transportation conformity determinations. - COMMUTER Model (ZIP XLS, 13MB)
An EPA assessment tool that provides estimates on how commuter benefits can impact nitrogen oxide, particulate matter and air toxic emissions, and fuel use and costs. - Commuter Model v2.0 Coefficients (PDF) (295KB, EPA420-B-05-019, October, 2005)
An explanation and listing of mode-choice coefficients used in the COMMUTER model. - Commuter Model v2.0 User Manual (PDF) (1.8MB, EPA420-B-05-017, October, 2005)
Manual for the COMMUTER model. - Procedures Manual for the Commuter Model v2.0 (PDF) (1MB, EPA420-B-05-018, October, 2005)
Procedures for operating the COMMUTER model.
- Guidance for Quantifying and Using Emission Reductions from Best Workplaces for Commuter Programs in State Implementation Plans and Transportation Conformity Determinations (2.2MB, EPA-420-B-07-015, October, 2007)
Fuels
- Guidance on Quantifying NOx Benefits for Cetane Improvement Programs for Use in SIPs and Transportation Conformity (PDF) (253KB)
Guidance that outlines EPA's policy for giving SIP credit for emission reductions attributable to the use of cetane additives in diesel fuel. - Guidance on Use of Opt-In to Reformulated Gasoline (RFG) and Low Reid Vapor Pressure (RVP) Requirements in Ozone SIPs (PDF) (42KB)
Guidance outlining the statutory requirements that address fuel controls and their use in a SIP.
Idling
- Locomotive Idling Guidance (PDF) (343KB)
Guidance for quantifying and using long duration switch yard locomotive idling emission control programs in State Implementation Plans and transportation conformity. - Truck Idling Guidance (PDF) (378KB)
Guidance for quantifying and using long duration truck idling emission control programs in State Implementation Plans and transportation conformity.
Intelligent Transportation Systems Management
- Assessing the Emissions and Fuel Consumption Impacts of Intelligent Transportation Systems (ITS) (PDF) (506KB)
A study that describes the types of modeling approaches needed to capture the short- and long-term transportation, emissions, and fuel consumption impacts of ITS deployment.
Land Use
- Background Information for Land Use SIP Policy (PDF) (736KB)
A report summarizing efforts by states to take SIP credit for land use strategies and areas where additional policies are needed to support effective land use SIP policies. - Comparing Methodologies to Assess Transportation and Air Quality Impacts of Brownfields and Infill Development (PDF) (1.4MB)
A report describing and comparing four methods for characterizing the air quality benefits resulting from infill development. This report is a companion piece to EPA's policy guidance entitled, "Improving Air Quality Through Land Use Activities." - Evaluation of Modeling Tools for Assessing Land Use Policies and Strategies (PDF) (244KB)
An EPA-sponsored report addressing the relationship between land use, mobility, and vehicle miles traveled; provides an assessment of various travel demand and land use modeling tools. - Granting Air Quality Credit for Land Use Measures: Policy Options (PDF) (180KB)
A study that analyzes policy options for recognizing and providing credit for sustainable land use activities when specific control measures are employed. - Improving Air Quality Through Land Use Activities (PDF) (1.8MB)
Guidance to assist air quality and transportation planners in accounting for the air quality impacts of voluntary land use policies and projects.
Retrofits
- Guidance for Mobile Emission Credit Generation by Urban Buses
Guidance documents that outline federal policies supporting urban bus retrofit/clean fuel use in large metropolitan areas. - Diesel Retrofits: Quantifying and Using Their Benefits in SIPs and Conformity - Guidance for State and Local Air and Transportation Agencies
Guidance document and fact sheet for quantifying and using emission reductions from retrofitted diesel vehicles, engines, and equipment. This guidance applies to both highway vehicles (such as buses and trucks) and nonroad vehicles, engines, and equipment (such as construction equipment). - SmartWay SIP and Conformity Guidance (PDF) (35 pp, 306K, EPA420-B-07-004, June 2007)
This document describes how to quantify and use reductions in nitrogen oxides (NOx) that result when trucks are outfitted with two specific SmartWay fuel-efficient technologies: trailer aerodynamic kits and low-rolling resistant tires.- Fact Sheet (Also available as a PDF file, 3 pp, 106K, EPA420-F-07-045, June 2007)
Contact: Gary Dolce, phone: (734) 214-4414, email: dolce.gary@epa.gov
Transportation Control Measures
- Benefits Estimates for Selected Transportation Control Measure (TCM) Programs (PDF) (677KB)
A report that quantifies TCMs that have been implemented, and outlines the methodologies used for estimating their emission and travel activity effects. - Methodologies for Estimating Emission and Travel Activity Effects of TCMs (PDF) (5.3MB)
An overview of several different methodologies available for assessing the potential emission reductions associated with transportation control measures. - Transportation Control Measure: State Implementation Plan Guidance (EPA 450/2-89-020) (PDF) (11.2MB)
This document lists approval criteria that needs to be met so that a transportation control measure (TCM) may be incorporated into a SIP. The guidance also directs states to use additional TCM-specific guidance where available. - Index of Transportation Measure Quantification Efforts: Methodology Matrix (September 1998) (PDF) (1MB)
A listing of summaries on a broad range of studies that have been conducted to evaluate the effectiveness of transportation control measures. - Transportation Control Measure Information Documents
A report that describes variations in implementation, examples, expected transportation and emission impacts, and other important considerations for the 16 broad categories of TCMs as required and described under Section 108(f) of the Clean Air Act. (All of the following are PDF files)- Executive Summary (2.1MB)
- Transportation/Air Quality Background Information (2.8MB)
- Accelerated Retirement of Vehicles (1MB)
- Activity Centers (2.8MB)
- Area-Wide Rideshare Incentives (2.2MB)
- Bicycle and Pedestrian Programs (1.7MB)
- Employer-Based Transportation Management Programs (2.1MB)
- Extended Vehicle Idling (471KB)
- Extreme Low-Temperature Cold Starts (538KB)
- High Occupancy Vehicle Lanes (1.3MB)
- Improved Public Transit (2.4MB)
- Park-and-Ride/Fringe Parking (1.6MB)
- Parking Management (1.6MB)
- Special Events (1.9MB)
- Traffic Flow Improvements (1.6MB)
- Trip Reduction Ordinances (3.6MB)
- Vehicle Use Limitations/Restrictions (1.9MB)
- Work Schedule Changes (1.7MB)
Transportation Pricing
- Opportunities to Improve Air Quality through Transportation Pricing Programs (PDF) (603KB)
A document that provides general information on pricing programs, including pricing program advantages, the institutional relationships necessary for pricing measures to work, and some pitfalls to avoid in implementing a program. - Technical Methods for Analyzing Pricing Measures to Reduce Transportation Emissions (PDF) (1.8MB)
A report jointly funded by EPA and DOT that provides technical assistance on best practice approaches for analyzing various transportation pricing policies.