Abbreviations and Definitions

Table 1-2 below lists the common abbreviations used throughout this manual. Other more specific abbreviations will be defined later in the appropriate chapters.

Table 1-2. Common Abbreviations
Abbreviation	Term
APT	Advance Preemption Time
AREMA	American Railway Engineering and Maintenance-of-Way Association
CFR	Code of Federal Regulations
ERT	Equipment Response Time
FHWA	Federal Highway Administration
FRA	Federal Railroad Administration
ITE	Institute of Transportation Engineers
MT	Minimum Time
TMUTCD	Texas Manual on Uniform Traffic Control Devices
TxDOT	Texas Department of Transportation
RRD-RSS	Rail Division-Rail Safety Section (TxDOT)
RRD	Rail Division (TxDOT)

Table 1-3 lists some common definitions used throughout this manual. Other more specific definitions will be defined later in the appropriate chapters.

Table 1-3. Common Definitions
Term	Definition
Grade Crossing Warning System	The flashing-light signals, with or without crossing gates, together with the necessary control equipment used to inform road users of the approach or presence of rail traffic at a grade crossing.
At-Grade Crossing (Grade Crossing)	The general area where a highway and a railroad and/or light rail transit route cross at the same level, within which are included the tracks, highway, and traffic control devices for traffic traversing that area.
Diagnostic Team	A group of knowledgeable representatives of the parties of interest in a grade crossing or group of grade crossings (see 23 CFR Part 646.204). A railroad company signal maintainer, local government representative, and FHWA or FRA representative are also included as needed (TxDOT Rail-Highway Operations Manual, pg. 4-9).
Highway Agency	Agency that owns or has jurisdiction over the relevant highway or roadway. The Highway Agency may be TxDOT or a local agency (City or County).
Interconnected Railroad Crossing	A railroad at-grade crossing which has an electrical connection between the railroad signal system and a traffic signal system for the purpose of providing preemption.
Railroad Company	Railroad company that owns, maintains, and/or operates at the relevant railroad grade crossing. Note: There may be multiple railroad companies at a given grade crossing.
Traffic Signal Interconnection	The electrical connection between the railroad signal system and the traffic signal system for the purpose of providing preemption.

Section 1: Overview