GLOSSARY
Term	Definition
Area Sources	Small stationary and non-transportation pollution sources that are too small and/or numerous to be included as point sources but may collectively contribute significantly to air pollution (e.g., dry cleaners).
Arterial Street	A class of street serving major traffic movements (high-speed, high volume) for travel between major points.
Attainment Area	An area considered to have air quality that meets or exceeds the U.S. Environmental Protection Agency (EPA) health standards used in the Clean Air Act. Nonattainment areas are areas considered not to have met these standards for designated pollutants. An area may be an attainment area for one pollutant and a nonattainment area for others.
Capacity	A transportation facility's ability to accommodate a moving stream of people or vehicles in a given time period.
Capital Program Funds	Financial assistance from the Capital Program of 49 U.S.C. This program enables the Secretary of Transportation to make discretionary capital grants and loans to finance public transportation projects divided among fixed guideway (rail) modernization; construction of new fixed guideway systems and extensions to fixed guideway systems; and replacement, rehabilitation, and purchase of buses and rented equipment, and construction of bus-related facilities.
Carbon Monoxide (CO)	A colorless, odorless, tasteless gas formed in large part by incomplete combustion of fuel. Human activities (i.e., transportation or industrial processes) are largely the source for CO contamination.
Clean Air Act (CAA)	The original Clean Air Act was passed in 1963, but the national air pollution control program is actually based on the 1970 version of the law. The 1990 Clean Air Act Amendments are the most far-reaching revisions of the 1970 law. The 1990 Clean Air Act is the most recent version of the 1970 version of the law. The 1990 amendments made major changes in the Clean Air Act.
Congestion Management System (CMS)	Systematic process for managing congestion. Provides information on transportation system performance and finds alternative ways to alleviate congestion and enhance the mobility of people and goods, to levels that meet state and local needs.
Congestion Mitigation & Air Quality Improvement Program	A categorical Federal-aid funding program created with the ISTEA. Directs funding to projects that contribute to meeting National air quality standards. CMAQ funds generally may not be used for projects that result in the construction of new capacity available to SOVs (single-occupant vehicles).
Department of Transportation (DOT)	When used alone, indicates U.S. Department of Transportation. In conjunction with a place name, indicates state, city, or county transportation agency (e.g., Illinois DOT, Los Angeles DOT).
Emissions Budget	The part of the State Implementation Plan (SIP) that identifies the allowable emissions levels, mandated by the National Ambient Air Quality Standards (NAAQS), for certain pollutants emitted from mobile, stationary, and area sources. The emissions levels are used for meeting emission reduction milestones, attainment, or maintenance demonstrations.
Environmental Justice (EJ)	Environmental justice assures that services and benefits allow for meaningful participation and are fairly distributed to avoid discrimination.
Environmental Protection Agency (EPA)	The federal regulatory agency responsible for administering and enforcing federal environmental laws, including the Clean Air Act, the Clean Water Act, the Endangered Species Act, and others.
Federal Highway Administration (FHWA)	A branch of the US Department of Transportation that administers the federal-aid Highway Program, providing financial assistance to states to construct and improve highways, urban and rural roads, and bridges. The FHWA also administers the Federal Lands Highway Program, including survey, design, and construction of forest highway system roads, parkways and park roads, Indian reservation roads, defense access roads, and other Federal lands roads.
Federal Transit Administration (FTA)	A branch of the US Department of Transportation that is the principal source of federal financial assistance to America's communities for planning, development, and improvement of public or mass transportation systems. FTA provides leadership, technical assistance, and financial resources for safe, technologically advanced public transportation to enhance mobility and accessibility, to improve the Nation's communities and natural environment, and to strengthen the national economy.
Financial Planning	The process of defining and evaluating funding sources, sharing the information, and deciding how to allocate the funds.
Financial Programming	A short-term commitment of funds to specific projects identified in the regional Transportation Improvement Program (see TIP).
Fine Particulates	Particulate matter less than 2.5 microns in size (PM-2.5). A micron is one millionth of a meter. See "Particulate matter" below.
Fiscal Constraint	Making sure that a given program or project can reasonably expect to receive funding within the time allotted for its implementation.
Formula Capital Grants	Federal transit funds for transit operators; allocation of funds overseen by FTA.
Geographic Information System (GIS)	Computerized data management system designed to capture, store, retrieve, analyze, and display geographically referenced information.
High-Occupancy Vehicle (HOV)	Vehicles carrying two or more people. The number that constitutes an HOV for the purposes of HOV highway lanes may be designated differently by different transportation agencies.
Intelligent Transportation Systems (ITS)	The application of advanced technologies to improve the efficiency and safety of transportation systems.
Intermodal	The ability to connect, and the connections between, modes of transportation.
Intermodal Surface Transportation Efficiency Act of 1991 (ISTEA)	Legislative initiative by the US Congress that restructured funding for transportation programs; authorized an increased role for regional planning commissions/MPOs in funding decisions; and required comprehensive regional and statewide long-term transportation plans.
Interstate Highway System (IHS)	The system of highways that connects the principal metropolitan areas, cities, and industrial centers of the United States. Also connects the US to internationally significant routes in Canada and Mexico.
Land Use	Refers to the manner in which portions of land or the structures on them are used, i.e. commercial, residential, retail, industrial, etc.
Long-Range Transportation Plan (LRTP)	A document resulting from regional or statewide collaboration and consensus on a region or state's transportation system, and serving as the defining vision for the region's or state's transportation systems and services. In metropolitan areas, the plan indicates all of the transportation improvements scheduled for funding over the next 20 years.
Maintenance Area	Maintenance area is any geographic region of the United States previously designated nonattainment pursuant to the CAA Amendments of 1990 and subsequently redesignated to attainment subject to the requirement to develop a maintenance plan under section 175A of the CAA, as amended.
Metropolitan Planning Organization (MPO)	Regional policy body, required in urbanized areas with populations over 50,000, and designated by local officials and the governor of the state. Responsible in cooperation with the state and other transportation providers for carrying out the metropolitan transportation planning requirements of federal highway and transit legislation.
Metropolitan Transportation Plan (MTP)	The official intermodal transportation plan that is developed and adopted through the metropolitan transportation planning process for the metropolitan planning area, in accordance with 23 U.S.C. 134, 23 USC 135 and 49 U.S.C. 5303.
Mobile Source	The mobile source-related pollutants are carbon monoxide (CO), hydrocarbons (HC), nitrogen oxides (NOx), and particulate matter (PM-10 and PM 2.5).
Mode	A specific form of transportation, such as automobile, subway, bus, rail, or air.
National Ambient Air Quality Standards (NAAQS)	Federal standards that set allowable concentrations and exposure limits for various pollutants. The EPA developed the standards in response to a requirement of the CAA. Air quality standards have been established for the following six criteria pollutants: ozone (or smog), carbon monoxide, particulate matter, nitrogen dioxide, lead, and sulfur dioxide.
National Environmental Policy Act of 1969 (NEPA)	Established a national environmental policy requiring that any project using federal funding or requiring federal approval, including transportation projects, examine the effects of proposed and alternative choices on the environment before a federal decision is made.
National ITS Architecture	A systems framework to guide the planning and deployment of ITS infrastructure. The national ITS architecture is a blueprint for the coordinated development of ITS technologies in the U.S. It is unlikely that any single metropolitan area or state would plan to implement the entire national ITS architecture.
Non-attainment	Any geographic area that has not met the requirements for clean air as set out in the Clean Air Act of 1990.
Ozone 03)	Ozone is a colorless gas with a sweet odor. Ozone is not a direct emission from transportation sources. It is a secondary pollutant formed when VOCs and NOx combine in the presence of sunlight. Ozone is associated with smog or haze conditions. Although the ozone in the upper atmosphere protects us from harmful ultraviolet rays, ground-level ozone produces an unhealthy environment in which to live. Ozone is created by human and natural sources.
Particulate Matter (PM10 and PM2.5)	Particulate matter consists of airborne solid particles and liquid droplets. Particulate matter may be in the form of fly ash, soot, dust, fog, fumes, etc. These particles are classified as "coarse" if they are smaller than 10 microns, or "fine" if they are smaller than 2.5 microns. Coarse airborne particles are produced during grinding operations, or from the physical disturbance of dust by natural air turbulence processes, such as wind. Fine particles can be a by-product of fossil fuel combustion, such as diesel and bus engines. Fine particles can easily reach remote lung areas, and their presence in the lungs is linked to serious respiratory ailments such as asthma, chronic bronchitis and aggravated coughing. Exposure to these particles may aggravate other medical conditions such as heart disease and emphysema and may cause premature death. In the environment, particulate matter contributes to diminished visibility and particle deposition (soiling).
Performance Measures	Indicators of how well the transportation system is performing with regard to such things as average speed, reliability of travel, and accident rates. Used as feedback in the decisionmaking process.
Planning Funds (PL)	Primary source of funding for metropolitan planning designated by the FHWA.
Public Participation	The active and meaningful involvement of the public in the development of transportation plans and programs.
Smart Growth	A set of policies and programs design to protect, preserve, and economically develop established communities and valuable natural and cultural resources.
Sources	Refers to the origin of air contaminants. Can be point (coming from a defined site) or non-point (coming from many diffuse sources).[Stationary sources include relatively large, fixed facilities such as power plants, chemical process industries, and petroleum refineries. Area sources are small, stationary, non-transportation sources that collectively contribute to air pollution, and include such sources as dry cleaners and bakeries, surface coating operations, home furnaces, and crop burning. Mobile sources include on-road vehicles such as cars, trucks, and buses; and off-road sources such as trains, ships, airplanes, boats, lawnmowers, and construction equipment.
Sprawl	Urban form that connotatively depicts the movement of people from the central city to the suburbs. Concerns associated with sprawl include loss of farmland and open space due to low-density land development, increased public service costs, and environmental degradation as well as other concerns associated with transportation.
Stakeholders	Individuals and organizations involved in or affected by the transportation planning process. Include federal/state/local officials, MPOs, transit operators, freight companies, shippers, and the general public.
State Infrastructure Bank (SIB)	A revolving fund mechanism for financing a wide variety of highway and transit projects through loans and credit enhancement. SIBs are designed to complement traditional Federal-aid highway and transit grants by providing States increased flexibility for financing infrastructure investments.
State Implementation Plan (SIP)	Produced by the state environmental agency, not the MPO. A plan mandated by the CAA that contains procedures to monitor, control, maintain, and enforce compliance with the NAAQS. Must be taken into account in the transportation planning process.
State Planning and Research Funds (SP&R)	Primary source of funding for statewide long-range planning.
Statewide Transportation Plan	The official statewide intermodal transportation plan that is developed through the statewide transportation planning process.
State Transportation Improvement Program (STIP)	A staged, multi-year, statewide, intermodal program of transportation projects, consistent with the statewide transportation plan and planning processes as well as metropolitan plans, TIPs, and processes.
Surface Transportation Program (STP)	Federal-aid highway funding program that funds a broad range of surface transportation capital needs, including many roads, transit, sea and airport access, vanpool, bike, and pedestrian facilities.
Telecommuting	Communicating electronically (by telephone, computer, fax, etc.) with an office, either from home or from another site, instead of traveling to it physically.
Title VI	Title VI of the Civil Rights Act of 1964. Prohibits discrimination in any program receiving federal assistance.
Transportation Conformity	Process to assess the compliance of any transportation plan, program, or project with air quality implementation plans. The conformity process is defined by the Clean Air Act.
Transportation Control Measures (TCM)	Transportation strategies that affect traffic patterns or reduce vehicle use to reduce air pollutant emissions. These may include HOV lanes, provision of bicycle facilities, ridesharing, telecommuting, etc. Such actions may be included in a SIP if needed to demonstrate attainment of the NAAQS.
Transportation Demand Management (TDM)	Programs designed to reduce demand for transportation through various means, such as the use of transit and of alternative work hours.
Transportation Equity Act for the 21st Century (TEA-21)	Authorized in 1998, TEA-21 authorized federal funding for transportation investment for fiscal 1998-2003. Approximately $217 billion in funding was authorized, the largest amount in history, which is used for highway, transit, and other surface transportation programs.
Transportation Improvement Program (TIP)	A document prepared by a metropolitan planning organization that lists projects to be funded with FHWA/FTA funds for the next one- to three-year period.
Transportation Infrastructure	A federal credit program under which the USDOT may provide three forms of credit assistance - secured (direct) loans, loan guarantees, and standby lines of credit - for surface transportation projects of national or regional significance. The fundamental goal is to leverage federal funds by attracting substantial private and non-federal co-investment in critical improvements to the nation's surface transportation system.
Transportation Management Area (TMA)	All urbanized areas over 200,000 in population, and any other area that requests such designation.
Trust Fund	A fund credited with receipts that are held in trust by the government and earmarked by law for use in carrying out specific purposes and programs in accordance with an agreement or a statute.
Unified Planning Work Program (UPWP)	The management plan for the (metropolitan) planning program. Its purpose is to coordinate the planning activities of all participants in the planning process.
Urbanized Area	Area that contains a city of 50,000 or more population plus incorporated surrounding areas meeting size or density criteria as defined by the U.S. Census.

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