[Code of Federal Regulations]
[Title 49, Volume 4]
[Revised as of October 1, 2004]
From the U.S. Government Printing Office via GPO Access
[CITE: 49CFR232.403]

[Page 506-507]
 
                        TITLE 49--TRANSPORTATION
 
       CHAPTER II--FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF 
                             TRANSPORTATION
 
PART 232_BRAKE SYSTEM SAFETY STANDARDS for FREIGHT and OTHER NON-PASSENGER 
TRAINS and EQUIPMENT; END-of-TRAIN DEVICES--Table of Contents
 
                     Subpart E_End-of-Train Devices
 
Sec. 232.403  Design standards for one-way end-of-train devices.

    (a) General. A one-way end-of-train device shall be comprised of a 
rear-of-train unit (rear unit) located on the last car of a train and a 
front-of-train unit (front unit) located in the cab of the locomotive 
controlling the train.
    (b) Rear unit. The rear unit shall be capable of determining the 
brake pipe pressure on the rear car and transmitting that information to 
the front unit for display to the locomotive engineer. The rear unit 
shall be--
    (1) Capable of measuring the brake pipe pressure on the rear car 
with an accuracy of 3 pounds per square inch 
(psig) and brake pipe pressure variations of 1 
psig;
    (2) Equipped with a ``bleeder valve'' that permits the release of 
any air under pressure from the rear of train unit or the associated air 
hoses prior to detaching the rear unit from the brake pipe;
    (3) Designed so that an internal failure will not cause an undesired 
emergency brake application;
    (4) Equipped with either an air gauge or a means of visually 
displaying the

[[Page 507]]

rear unit's brake pipe pressure measurement; and
    (5) Equipped with a pressure relief safety valve to prevent 
explosion from a high pressure air leak inside the rear unit.
    (c) Reporting rate. Multiple data transmissions from the rear unit 
shall occur immediately after a variation in the rear car brake pipe 
pressure of 2 psig and at intervals of not greater 
than 70 seconds when the variation in the rear car brake pipe pressure 
over the 70-second interval is less than 2 psig.
    (d) Operating environment. The rear unit shall be designed to meet 
the performance requirements of paragraphs (b) and (c) of this section 
under the following environmental conditions:
    (1) At temperatures from -40 [deg]C to 60 [deg]C;
    (2) At a relative humidity of 95% noncondensing at 50 [deg]C;
    (3) At altitudes of zero to 12,000 feet mean sea level;
    (4) During vertical and lateral vibrations of 1 to 15 Hz., with 0.5 
g. peak to peak, and 15 to 500 Hz., with 5 g. peak to peak;
    (5) During the longitudinal vibrations of 1 to 15 Hz., with 3 g. 
peak to peak, and 15 to 500 Hz., with 5 g. peak to peak; and
    (6) During a shock of 10 g. peak for 0.1 second in any axis.
    (e) Unique code. Each rear unit shall have a unique and permanent 
identification code that is transmitted along with the pressure message 
to the front-of-train unit. A code obtained from the Association of 
American Railroads, 50 F Street, NW., Washington, DC 20036 shall be 
deemed to be a unique code for purposes of this section. A unique code 
also may be obtained from the Office of Safety Assurance and Compliance 
(RRS-10), Federal Railroad Administration, Washington, DC 20590.
    (f) Front unit. (1) The front unit shall be designed to receive data 
messages from the rear unit and shall be capable of displaying the rear 
car brake pipe pressure in increments not to exceed one pound.
    (2) The display shall be clearly visible and legible in daylight and 
darkness from the engineer's normal operating position.
    (3) The front device shall have a means for entry of the unique 
identification code of the rear unit being used. The front unit shall be 
designed so that it will display a message only from the rear unit with 
the same code as entered into the front unit.
    (4) The front unit shall be designed to meet the requirements of 
paragraphs (d)(2), (3), (4), and (5) of this section. It shall also be 
designed to meet the performance requirements in this paragraph under 
the following environmental conditions:
    (i) At temperatures from 0 [deg]C to 60 [deg]C;
    (ii) During a vertical or lateral shock of 2 g. peak for 0.1 second; 
and
    (iii) During a longitudinal shock of 5 g. peak for 0.1 second.
    (g) Radio equipment. (1) The radio transmitter in the rear unit and 
the radio receiver in the front unit shall comply with the applicable 
regulatory requirements of the Federal Communications Commission (FCC) 
and use of a transmission format acceptable to the FCC.
    (2) If power is supplied by one or more batteries, the operating 
life shall be a minimum of 36 hours at 0 [deg]C.