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Glossary of Terms

Glossary of Terms

AAR—American Association of Railroads

AASHTO—American Association of State Highway and Transportation Officials

ARRA—American Recovery and Reinvestment Act of 2009, an economic stimulus package based on proposals of President Obama, enacted by the 111th United States Congress, February 2009

DOT—Department of Transportation

Double-Stack Clearance—Where grade-separated clearances of bridges, tunnels, or other infrastructure allow for double-stack intermodal containers

FHWA—Federal Highway Administration

FHWA Freight Analysis Framework—The Freight Analysis Framework incorporates data from an array of sources to estimate commodity flows and freight transportation activities among states, regions, and major international gateways

FRA—Federal Railroad Administration

FTA—Federal Transit Administration

GIS—Geographical Information Systems. GIS utilizes computer hardware and software to allow users to spatially analyze and report data through maps, globes, and reports which can demonstrate spatial trends and themes

Granularity—The extent to which a system can be divided into smaller components for analysis of individual parts or pieces of the system

Greenhouse Gasses—The primary greenhouse gasses include carbon dioxide (CO2), nitrogen oxide (NOX), and particulate matter (PM). These gasses and particulates, augmented by the transportation system, contribute to the warming of the earth’s surface, known as the greenhouse effect

HERS-ST—Highway Economic Requirement System, state edition, developed by FHWA

HSIRP—High-Speed Intercity Rail Program

Intermodal—Use of more than one type of transportation mode for transporting goods or passengers

ISTEA—Intermodal Surface Transportation Efficiency Act (1991). This bill presented an intermodal approach to highway and transit funding that included collaborative planning requirements and gave additional powers to metropolitan planning organizations

LRFA/LRSA—The Regional Rail Reorganization Act of 1973 established the Local Rail Service Assistance (LRSA) to provide financial support to states for the continuation of rail freight service on abandoned light density lines in the Northeast. Over time, the program was expanded to all states. The act was renamed the Local Freight Rail Assistance Act (LRFA) when reauthorized in 1989

MPO—Metropolitan Planning Organization. In 1962, the U.S. Congress passed legislation that any urbanized area with a population greater than 50,000 must establish an MPO to serve as a transportation planning/policy creating body made up of local government and transportation authorities. Federal funding for programs and projects is channeled through the MPO

NTAD—National Transportation Atlas Database

Passenger Rail Investment and Improvement Act (PRIIA)—Signed into law by President George W. Bush in October 2008, PRIIA outlines a set of requirements for state rail plans that states must fulfill to become eligible for Intercity Passenger Rail grants

Passing Capacity—On double-track and multiple-track segments, including sidings, allow for two-way running of trains and more efficient shared passenger and freight operations

Positive Train Control—The FRA defines “positive train control system” as a system designed to prevent a) collisions between trains; b) overspeed derailments (derailments caused when a train exceeds speed limits); c) incursions into established work zone limits (i.e., for roadway workers maintaining track); and d) the movement of a train through an improperly positioned switch

RISA—Rail Safety Improvement Act, signed by President George W. Bush in 2008, requires passenger and certain freight trains have high-tech emergency braking systems by 2015

RTC—Rail Traffic Controller, a rail simulation model

SAFETEA-LU—Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users, enacted August 10, 2005. Building on ISTEA’s collaborative planning focus, SAFETEA-LU requires states and MPOs to enhance transportation planning activities related to security, safety, freight, and environment

SCORT—AASHTO's Standing Committee on Rail Transportation

STB—U.S. Surface Transportation Board

STRACNET—Department of Defense designated network of strategically important rail lines and connectors to link military reservations to maritime ports

TEA 21—The Transportation Equity Act for the 21st Century (1998). Built upon ISTEA programs and added initiatives to improve safety, protect communities and the environment, and advance economic growth and competitiveness through efficient and flexible transportation

TIGER Discretionary Grants—Transportation Investment Generating Economic Recovery Discretionary Grants (2009) support high impact transportation projects. Eligible projects include: highway or bridge projects, public transportation, passenger and freight rail transportation projects, and port infrastructure investments

TOD—Transit Oriented Development—a proven method to effectively integrate transit rail projects, especially stations and terminals, into the fabric of a community. The principles of TOD promote walkable, higher-density, and mixed-use development

URCS—Uniform Rail Costing System

VMT—Vehicle miles traveled