Skip to content

Glossary of Terms/Acronyms

Home » Resources » Glossary of Terms/Acronyms

A | B | C | D | E | F | G | H | I | J | K | L | N | O | P | Q | R | S | T | U | V | W | X | Y | Z


AASHTO – American Association of State Highway and Transportation Officials

ADA – Americans with Disabilities Act of 1990: Regulations implementing the ADA require transportation agencies to make certain improvements to the infrastructure and some of these improvements have to be specifically identified in the Transportation Improvement Program. 

Allocation – An administrative distribution of funds among the States, or among subunits in a metropolitan area, done for funds that do not have statutory distribution of funds. 

AMPO – Association of Metropolitan Planning Organizations 

Apportionment – A term that refers to a statutorily prescribed division or assignment of funds. An apportionment is based on prescribed formulas in the law and consists of dividing authorized obligation authority for a specific program among the States.   

Appropriations – Action of a legislative body that makes funds available for expenditure with specific limitations as to amount, purpose, and duration. The amount of funding appropriated may be less than what was authorized. In most cases, it permits money previously authorized to be obligated and payments made, but for the highway program operating under contract authority, appropriations specify amounts of funds that Congress will make available to liquidate prior obligations.  

Authorization – Basic substantive legislation or that which empowers an agency to implement a particular program; also establishes an upper limit on the amount of funds that can be appropriated for that program and creates the policy and structure of a program, including formulas and guidelines, for awarding funds. Revenues to be spent under an authorization must be appropriated by separate legislation. 

Average Daily Traffic (ADT) – The average number of vehicles passing a specific point in a 24-hour period, often measured throughout a year. It is a standard measurement for vehicle traffic-load on a section of road and is used when making transportation planning decisions.


BOT – The North Carolina Board of Transportation is composed of 20 people from across the state. Each member represents a specific transportation division or is an at-large, state-wide member. All members work with the Secretary of Transportation and team to make decisions about transportation priorities.

Budget Authority – Empowerment by the Congress that allows Federal agencies to incur obligations to spend or lend money. This empowerment is generally in the form of appropriations. However, for the major highway program categories, it is in the form of “contract authority”. Budget authority permits agencies to obligate all or part of the funds that were previously “authorized”. Without budget authority, Federal agencies cannot commit the Government to make expenditures or loans.

Bus Rapid Transit (BRT) – An exclusive right of way for buses separated from other vehicular traffic. The purpose of BRT is to provide reliable travel times for riders. 


Capital Budget – A plan of proposed capital outlays and means of financing them.

Capital Cost – Costs associated with improvements to or expansions of the physical capacity of the transportation systemincluding both facilities and vehicles.

Capital Program – A plan for capital expenditures to be incurred each year over a fixed period of years to meet capital needs. 

Carbon Monoxide (CO) – A colorless, odorless, tasteless gas formed in large part by incomplete combustion of fuel. Human activities such as transportation or industrial processes are largely the source for CO emissions. 

Categorical Exclusion(CE) – One of three types of environmental documentation under the National Environmental Policy Act (NEPA). 

CATS – Charlotte Area Transit System

CDOT – Charlotte Department of Transportation

Charlotte Railroad Improvement and Safety Program (CRISP) – Formed in order to modernize existing track infrastructure in and around Charlotte with a planning/design window of 50 years, CRISP hopes to improve speed and capacity of rail infrastructure, safety and efficiency of freight commerce and transit, and safety for vehicles and pedestrians. 

Charlotte Regional Alliance for Transportation (CRAFT) – An alliance of the four MPOs and two RPOs in the greater Charlotte region was created to enhance communication among jurisdictions, promote awareness of regional concerns and provide an educational forum to address significant common issues. Members include the CRTPO, Cabarrus-Rowan MPO, Gaston-Cleveland-Lincoln MPO; Rock Hill – Fort Mill Transportation Study, and Rocky River RPO.   

CIP – Capital Improvements Program 

Clean Air Act (CAA) – The Clean Air Act is the law that defines EPA’s responsibilities for protecting and improving the nation’s air quality and the stratospheric ozone layer. The last major change in the law, the Clean Air Act Amendments of 1990, was enacted by Congress in 1990. Legislation passed since then has made several minor changes. 

Comprehensive Transportation Plan (CTP) – NC General Statute 136-66.2 requires each municipality or MPO, with the cooperation of the NCDOT, to develop a CTP serving present and anticipated travel demand in and around the municipality or MPO. 

Congestion Management Process (CMP) – A systematic approach required in TMAs that provides for effective management and operation, based on a cooperatively developed and implemented metropolitan-wide strategy of new and existing transportation facilities. 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. CRTPO is classified as a TMA. 

Congestion Mitigation and Air Quality Program (CMAQ) – The Congestion Mitigation and Air Quality Program provides funds for projects and activities which reduce congestion and improve air quality. To be eligible for CMAQ, projects and activities must contribute to the National Ambient Air Quality Standards and must be included in a Transportation Improvement Program.

Consultation – Occurs when one party confers with another identified party and, prior to taking actions(s) considers that party’s views. 

Contract Authority – A form of budget authority that permits obligations to be made in advance of appropriations. The Federal-Aid Highway Program operates mostly under contract authority rules. 

Cooperation – The parties involved in carrying out the transportation planning, programming, and management systems processes work together to achieve a common goal or objective. 

Coordination – The comparison of the transportation plans, program, and schedules of one agency with related plans, program and schedules of other agencies or entities with legal standing and adjustment of plans, program, and schedules, to achieve general consistency.

Council of Governments (COG)– Multipurpose, multijurisdictional public organizations created by local governments to respond to federal and state programs. The Centralina Regional Council is the COG for the CRTPO planning area.

CRMPO – Cabarrus-Rowan Metropolitan Planning Organization. RL Conrad Associates LLC serves as lead planning agency staff for the City of Concord.

CRTPO – Charlotte Regional Transportation Planning Organization. The lead planning agency is the City of Charlotte’s Planning, Design & Development Department.


DAQ – Division of Air Quality

Dedicated Funding Source – A funding source that, by law, is available for use only to support a specific purpose and cannot be diverted to other uses. Examples range from the Highway Trust Fund to local sales taxes.

DEIS – Draft Environmental Impact Statement

DENR – Department of Environment and Natural Resources (NCDENR for North Carolina)

Discretionary Funds – Any funds whose distribution is not automatic. Decision on the distribution of discretionary funds are usually made by an agency or person on the basis of that agency’s or person’s choice or judgment and in accordance with criteria set out in law or regulations. 

DOT – Department of Transportation (NCDOT for North Carolina)


Emissions Budget – The part of the SIP that identifies the allowable emissions levels, mandated by the 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 Assessment (EA) – One of three types of environmental documentation under the National Environmental Policy Act (NEPA).

Environmental Impact Statement(EIS) – One of three types of environmental documentation under the National Environmental Policy Act (NEPA). An environmental document that serves as a decision making tool. It provides a full and fair discussion of significant environmental impacts and informs decision makers and the public of the reasonable alternatives which would avoid or minimize adverse impacts or enhance the quality of the environment. 

Environmental Justice (EJ) – Assures that services and benefits allow for meaningful participation and are fairly distributed to avoid discrimination. A 1994 Presidential Executive Order directed every Federal agency to make EJ part of its mission. (See Title VI) 

EPA – Environmental Protection Agency

Evaluation Criteria – A process developed as part of the programming process for evaluating the relative merits of projects.  

Expenditure – Any allowable expense actually incurred in implementing a particular capital or operating or capital program. 


FAA – Federal Aviation Administration

Federal-aid Highways Program – The Federal-Aid Highway Program supports State highway systems by providing financial assistance for the construction, maintenance, and operations of the Nation’s 3.9-million-mile highway network, including the Interstate Highway System, primary highways, and secondary local roads. The Federal Highway Administration (FHWA) is charged with implementing the Federal-aid Highway Program in cooperation with the States and local government.

Federal Functional classification: The process by which streets and highways are grouped into classes, or systems, according to the character of service they are intended to provide. Federal-aid eligibility is contingent upon streets and highways being classified as minor collectors or higher.

Federal Implementation Plan (FIP) – A FIP is implemented to achieve attainment of air quality standards when a state does not or is unable to develop an adequate plan.

FEIS – Final Environmental Impact Statement 

FHWA – Federal Highway Administration, an agency of the U.S. Department of Transportation with jurisdiction over highways. 

Financial Planning – The development of financial information for decision-making including: information describing cost and revenue cash flow streams; knowledge and risks and uncertainties associated with financing proposed transportation projects and programs; information to determine the best way to raise capital for projects. 

Fiscally Constrained – Both the long-range transportation plan (MTP) and the TIP/STIP are required to be based on financial plans that are fiscally constrained. This means that these documents can only contain projects for which it is determined that funding sources are reasonably available over the life of the plan/program to pay for both the capital and operating cost of the proposed improvements.   

Flexible Funds – Money that can be invested in a range of transportation projects and that is not limited to one mode or another. Examples include Surface Transportation Program and the Congestion Mitigation and Air Quality program. 

FONSI – Finding of No Significant Impact, issued by the responsible federal agency at the close of an Environmental Assessment (EA) indicating that a proposed project will not have a significant environmental impact. 

Formula Funds – Funds distributed or apportioned to qualifying recipients on the basis of formulas described in law or regulations. 

FRA – Federal Railroad Administration 

FTA – Federal Transit Administration, an agency of the U.S. Department of Transportation with jurisdiction over transit.  


GCLMPO – Gaston-Cleveland-Lincoln Metropolitan Planning Organization. The lead planning agency is the City of Gastonia.

Geographic Information System (GIS) – A computer-based data management tool used for mapping, storing, retrieving, analyzing and displaying geographic data.

GHMPO – Greater Hickory Metropolitan Planning Organization. The lead planning agency is the Western Piedmont Council of Governments.


HOT – High Occupancy Toll lane 

HOV – High Occupancy Vehicle, or relates to a High Occupancy Vehicle lane 

HPMS – Highway Performance Monitoring System


ICATS – Iredell County Area Transportation System

IIJA – The Infrastructure Investments and Jobs Act (IIJA), also known as the Bipartisan Infrastructure Law (BIL), (H.R. 3684), was signed into law by President Joe Biden on November 15, 2021. The act includes $1.2 trillion in funding for transportation infrastructure improvements (including federal highway aid, transit, highway safety, motor carrier, research, hazardous materials, and rail programs of the Department of Transportation), broadband access, clean water, and electric grid renewal, in addition to other legislative actions. The IIJA is a reauthorization of the FAST Act and provides funding from Federal Fiscal Year (FFY) 2022 through FFY 2026.

INFRA – Infrastructure for Rebuilding America (federal grant program)

Intelligent Transportation System (ITS) – Examples of ITS include signal timing, electronic message boards, real-time travel information and automated vehicle locators (used by transit systems).

J, K, L

LAP -Locally Administered Projects

Least Environmentally Damaging Practicable Alternative (LEDPA) – Section 404 of the Clean Water Act (CWA) requires a permit for the discharge of “dredged or fill materials” into “waters of the United States.” To construct any project involving the discharge of dredged or fill material into U.S. waters, one must obtain a 404 permit from the United States Army Corps of Engineers.  

Level of Service (LOS) – A qualitative assessment of a road’s operating condition, generally described using a scale of A (little congestion) to F (severe congestion). 

Limitation on Obligations – Any action or inaction by an officer or employee of the United States that limits the amount of Federal assistance that may be obligated during a specific time period. A limitation on obligations does not affect the scheduled apportionment or allocation of funds; it just controls the rate at which these funds may be used. 

LPA – Lead Planning Agency. The City of Charlotte Planning, Design & Development Department is CRTPO’s Lead Planning Agency.


Maintenance Area (MA) – Any geographic region of the United States designated non-attainment pursuant to the Clean Air Act Amendments of 1990, and subsequently redesignated to attainment subject to the requirement to develop a maintenance plan under section 175A of the Clean Air Act as amended. 

Major Metropolitan Transportation Investment (MIS) – A high-type highway or transit improvement of substantial cost that is expected to have a significant effect on capacity, traffic flow, level of service, or mode share at the transportation corridor or subarea scale. Details on what is/is not considered a MIS are included in the definition section of 23 CFR 450.104.  

MCM – Metrolina CommunityViz Model

Metropolitan Planning Area – The geographic area in which the metropolitan transportation planning process must be carried out as required by 23 USC 134 and section 8 of the Federal Transit Act .  

Metropolitan Planning Organization (MPO) – The forum for cooperative transportation decision making for the metropolitan planning area. The MPO is designated by agreement among the Governor and the units of local governments representing 75 percent of the affected metropolitan population. 

Metropolitan Statistical Area (MSA & CMSA) – The Census classification for areas having a population over 50,000. The MSA may contain several urban areas, but contains one or more central city or cities. When commuting patterns of two MSAs have caused them to merge, the result is a Consolidated Metropolitan Statistical Area (CMSA).    

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. 

MOBILE – EPA’s Emission Factor Model 

MOU – Memorandum of Understanding 

MRM – Metrolina Regional Model (Travel Demand Model)

Multi-modal – Refers to the availability of multiple transportation options, especially within a system. A multi-modal approach to transportation planning focuses on the most efficient way of getting people or goods from place to place by truck, train, bicycle, automobile, airplane, bus, boat, foot or even a telecommuting or other technologies.


National Ambient Air Quality Standards (NAAQS) – The standards set by the Environmental Protection Agency, which a metropolitan area must meet for various pollutants in order to be considered an attainment area.  

National Environmental Policy Act (NEPA) – Signed into law in 1970 to establish a national environmental policy intentionally focused on Federal activities and the desire for a sustainable environment balanced with other essential needs of present and future generations of Americans. 

National Highway System (NHS) – This approximately 160,000 mile network consists of the 42,500 miles of the Interstate system, plus other key roads and arterials through the United States. Designated by Congress in 1995 pursuant to a requirement of the Intermodal Surface Transportation Efficiency Act, the NHS is designed to provide an interconnected system of principal routes to serve major travel destinations and population centers.  

NCAMPO – North Carolina Association of Metropolitan Planning Organization. The mission of NCAMPO is to positively affect policies and decision-making, to serve as a forum for communication, and to provide leadership in transportation planning amongst the 20 MPOs within North Carolina.

NCDOT – North Carolina Department of Transportation

NCDOT-IMD – North Carolina Department of Transportation – Integrated Mobility Division

NCDOT-TPD – North Carolina Department of Transportation – Transportation Planning Division

NCTA – North Carolina Turnpike Authority

Nonattainment Area (NAA) – Any geographic region of the United States that the Environmental Protection Agency (EPA) has designated as a nonattainment area for a transportation-related pollutant for which a National Ambient Air Quality Standard exists.

NOx – Nitrogen Oxide(s)


Obligation Authority (OA) – Another term for limitation on obligations (See that definition) 

Obligations – Commitment made by Federal agencies to pay out money as distinct from the actual payments, which are “outlays”. Generally, obligations are incurred after the enactment of budget authority. However, since budget authority in many highway programs is in the form of contract authority, obligations in these cases are permitted to be incurred immediately after apportionment or allocation. The obligations are for the Federal share of the estimated full cost of each project at the time it is approved regardless of when the actual payments are made or the expected time of project completion. Often funding programs come with restrictions that require a project sponsor to obligate funds in a timely manner or lose the funds. 

Operating Costs – Expenses associated with the general, day-to-day costs of running transportation systems. For transit, costs include fuel, salaries, and replacement parts. For roads, operating costs involve maintaining pavement, filling potholes, and paying workers’ salaries. 

Ozone (O3) – A colorless gas with a sweet odor, it is a secondary pollutant formed when VOCs and NOx combine in the presence of sunlight. It is associated with smog or haze conditions.


P7.0 – NCDOT Prioritization 7.0

PIP – Public Involvement Plan 

Planning Funds (PL) – The principal source of funding for carrying out the MPO process. 

PM – Particulate Matter (2.5 = 2.5 microns / 10 = 10 microns) 

Project Costs – All eligible expenditures expected to be associated with the funding of a project. These costs are legally able to be included in the principal amount of any bond issue used to finance the project. These outlays may include the costs of acquisition, construction costs, equipment use and acquisition costs, capitalized interest expenses, reserve funding requirement, printing cost, legal fees and the like. 

Project Oversight Committee (POC) – A subcommittee of the TCC.  The POC assists in the prioritization and project tracking efforts for the following direct attributable funding sources that have been appropriated to projects throughout the CRTPO planning area.

Programming – A process required under Federal statute and regulations (23 CFR Part 450) for developing a staged, prioritized, fiscally constrained, multi-year, intermodal program of projects for funding, consistent with the long-range transportation plan. States and local laws may also impose programming requirements that have to be coordinated with the federal effort.

Q, R

Reasonably Available -Those funds which are not yet currently available or committed but for which there is an identified strategy for ensuring that they will be available within the timeframe of the financial plan for the transportation plan/program. The strategy should include a plan of action that will be taken to obtain the new funding and past experiences with obtaining this type of funding.  

Record of Decision (ROD) – The final step in the EIS process; identifies the selected alternative, presents the basis for the decision, identifies all the alternatives considered, specifies the “environmentally preferred alternative” and provides information on the adopted means to avoid, minimize, and compensate for environmental impacts. 

Regionally Significant – A project that is on a facility which serves regional transportation needs (such as access to and from the area outside of the region, major activity centers in the region, major planned developments such as new retail malls, sports complexes, etc., or transportation terminals as well as most terminals themselves) and would normally be included in the modeling of a metropolitan area’s transportation network, including, as a minimum, all principal arterial highways and all fixed guideway transit facilities that offer a significant alternative to regional highway travel.  

Revenue Aligned Budget Authority – Highway program funding levels are tied to estimates of Highway Trust Fund (HTF) receipts made at the time of enactment of the Transportation Equity Act for the 21st Century (TEA-21) and the levels are adjusted each year to reflect the latest information of Highway Trust Fund receipts. The annual calculation of this adjustment, known as revenue aligned budget authority, or RABA, is intended to ensure that highway program funding tracks closely with actual and anticipated revenue to the Highway Account of the Highway Trust Fund.

RFATS – Rock Hill-Fort Mill Area Transportation Study. The lead planning agency is the City of Rock Hill.

RPO – Rural Planning Organization

RRRPO – Rocky River Rural Planning Organization. The lead planning agency is Stanly County.


SAFETEA-LU – Safe Accountable Flexible and Efficient Transportation Equity Act: A Legacy for Users 

SOV – Single Occupancy Vehicle 

SOx – Sulfur Oxide(s) 

Special Assessment – A compulsory levy made against certain property to defray part or all of the cost of a specific improvement or service deemed to primarily benefit those properties. 

Special District – An independent unit of local government organized to perform a restricted number of related governmental functions. Special Districts usually have the power to incur debt and levy taxes; however, certain types of special districts are entirely dependent on enterprise earnings and cannot levy taxes. 

SPOT – Strategic Planning Office of Transportation. This is a division within the NCDOT that administers the Prioritization process to develop the STIP in conjunction with the state’s MPOs and RPOs.

Stakeholders – Any group of individuals or organizations who are involved in the programming process whether that involvement is required by statute or regulation or simply because that individual has an interest in the outcome of the process. 

State Environmental Policy Act (SEPA) – The North Carolina Environmental Policy Act of 1971 sets the State’s environmental policies. The Act encourages the wise, productive, and beneficial use of the natural resources of the State without damage to the environment, and requires that State agencies consider and report upon environmental aspects and consequences of their actions involving the expenditure of public moneys or use of public land. 

State Implementation Plan (SIP) – The portion (or portions) of an applicable implementation plan approved or promulgated, or the most recent revision thereof, under section 110, 301(d) and 175A of the Clean Air Act. The SIP is a plan for how the state will achieve the National Ambient Air Quality Standard. 

Statewide Transportation Improvement Program (STIP) – A staged, multiyear, statewide intermodal program of transportation projects which is consistent with the statewide transportation plan and planning processes and metropolitan plans, TIPS and processes. 

Statewide Transportation Plan – The official statewide, intermodal transportation plan that is developed through the statewide transportation planning process. 

STI – Strategic Transportation Investments Legislation

Surface Transportation Block Grant – Direct Attributable (STBG-DA) – A discretionary funding source available to MPOs that have TMA designation (see Transportation Management Area definition). STBG-DA funds are to be used to advance projects across all modes of transportation. Projects must be in an adopted plan and Federal Aid eligible and are subject to federal compliance.

Surface Transportation Program (STP) – A funding program which provides flexibility of funds for highway and transit modes and for a category of funding known as transportation enhancements.


TDM -Travel Demand Management

Technical Coordinating Committee (TCC) – The TCC is composed of representatives of various departments, agencies, and communities involved in the transportation planning process. Its main function is to ensure coordination among agencies and to develop policy and project recommendations for matters that require CRTPO Board action. Virtually all CRTPO Board actions are accompanied by a TCC recommendation.

TIFIA – The Transportation Infrastructure Finance and Innovation Act of 1998: A program established which authorizes the U.S. DOT to provide secured (direct) loans, lines of credit and loan guarantees to public and private sponsors of eligible surface transportation projects. 

Title VI – Part of the Civil Rights Act of 1964, prohibits discrimination in any program receiving federal assistance. (See Environmental Justice) 

Transit Enhancements – A requirement designed to enhance the travel experience for public transit riders in Transportation Management Areas by requiring at least one percent of the area’s annual Section 5307 funds be spent on transit enhancements. Eligible projects include bus shelters, increased access by persons with disabilities, public art, rehabilitation and renovation of historic transit facilities and vehicles, landscaping, and bicycle and pedestrian access.

Transit Feasibility Study – A study undertaken to assess whether local transit services are needed for an area. 

Transit Providers Work Group (TPWG) – The TPWG was established to enhance collaboration amongst CRTPO planning area public transportation providers, coordinate on FTA Section 5303 and FTA Section 5307 MOU implementation and related activities, and provide transit planning education.

Transportation Advisory Committee (TAC) – A committee of elected officials within the local MPO responsible for communication and coordination between various policy boards and that takes action on issues in the transportation planning process. CRTPO does not use this term. 

Transportation Alternatives Program (TAP) – A funding source for bicycle, pedestrian, and “alternative” transportation projects, including projects previously eligible for Transportation Enhancement and Safe Routes to Schools Funding. The TAP program was originally established under the Moving Ahead for Progress in the 21st Century Act (MAP-21) and continued under the Fixing America’s Surface Transportation (FAST) Act.

Transportation and Community and System Preservation Program (TCSP) – A discretionary program which provides grants and research to investigate and address the relationship between transportation and community and system preservation.

Transportation Control Measures (TCM) – Actions that may be taken by state or local units of government related to the transportation systems’ contribution to the achievements of National Ambient Air Quality Standards.

Transportation Enhancement Activities (TEA) – A funding category which requires 10 percent of Surface Transportation Program monies to be set aside for projects that enhance the compatibility of transportation facilities with their surroundings. Examples of TEA projects include bicycle and pedestrian paths, restoration of rail depots or other historic transportation facilities, acquisition of scenic or open space lands next to travel corridors, and mural or other public art projects. 

Transportation Improvement Program (TIP) – A staged, prioritized, multi-year intermodal program of transportation projects, prepared in each metropolitan area, which is consistent with that area’s metropolitan transportation plan. Each metropolitan TIP is incorporated in its entirety into the STIP.     

Transportation Management Area (TMA) – An urban area with a population over 200,000 (as determined by the latest decennial census) or other area when TMA designation is requested by the Governor and the MPO (or affected local officials), and officially designated by the Administrators of the FHWA and FTA. The TMA designation applies to the entire metropolitan planning area(s). CRTPO is classified as a TMA. 

Transportation System Management (TSM) – An integrated set of strategies to optimize the performance of existing infrastructure through the implementation of multimodal and intermodal, cross-jurisdictional systems, services, and projects designed to preserve capacity and improve security, safety, and reliability of the transportation system. 

Trust Funds – Accounts established by law to hold receipts that are collected by the Federal Government and earmarked for specific purposes and programs. These receipts are not available for the general purposes of the Federal Government. The Highway Trust Fund is comprised of receipts from certain highway taxes (e.g., excise taxes on motor fuel, rubber, and heavy vehicles) and reserved for use for highway construction, mass transportation, and related purposes.


Unified Planning Work Program (UPWP) – A document produced every year by the MPO to describe all transportation-related planning activities that will be carried out during the next year. 

United States Code (USC) – 23 USC 134 is the part of the USC that governs the metropolitan transportation planning process. 

Urban Area (UA) – A census classification for areas having a population of 50,000 or more which meets certain population density requirements.


Vehicle Miles Traveled (VMT) – The total number of miles driven by all vehicles within a given time period and geographic area, it is used by regional transportation and environmental agencies for planning purposes. Since 1970, vehicle emissions have decreased even as vehicle miles traveled have increased.    

Volatile Organic Compound (VOC) – Emitted as gasses from certain solids or liquids, VOCs include a variety of chemicals, some of which may have short- and long-term adverse health effects.  Concentrations of VOCs are consistently higher indoors than outdoors. 

Volume/Capacity (V/C) – A ratio of volume to capacity: A ratio >1 indicates the facility is carrying more traffic than it can handle and improvements may be needed.

W, X, Y, Z

ZEV – Zero Emissions Vehicle