As used in this part:

(a) Train means a locomotive unit or locomotive units coupled, with or without cars, involved in a railroad operation conducted on a main track. It does not include yard movements.

(b) Commuter train means a short haul passenger train operating on track which is part of the general railroad system of transportation, within an urban, suburban or metropolitan area. It includes a passenger train provided by an instrumentality of a State or political subdivision thereof.

(c) Locomotive means a self-propelled unit of equipment designed for moving other equipment in revenue service and includes a self-propelled unit designed to carry freight or passenger traffic, or both.

(d) Main track means a track, other than an auxiliary track, extending through yards or between stations, upon which trains are operated by timetable or train order or both, or the use of which is governed by a signal system.

(e) Train order means mandatory directives issued as authority for the conduct of a railroad operation outside of yard limits.

(f) Red-orange-amber color range means those colors defined by chromaticity coordinates, as expressed in terms of the International Commission on Illumination's 1931 Colormetric System, which lie within the region bounded by the spectrum locus and lines defined by the following equations:

X + Y = .97 (white boundary)

Y = X − .12 (green boundary)

(g) Administrator means the Federal Railroad Administrator, the Deputy Administrator, or any official of the Federal Railroad Administration to whom the Administrator has delegated his authority under this part.

(h) Effective intensity means that intensity of a light in candela as defined by the Illuminating Engineering Society's Guide for Calculating the Effective Intensity of Flashing Signal Lights, November, 1964.

(i) Qualified person means any person who has the skill to perform the task and has received adequate instruction.

[42 FR 2321, Jan. 11, 1977; 42 FR 3843, Jan. 21, 1977, as amended at 51 FR 25185, July 10, 1986]