[Title 49 CFR 232.103]
[Code of Federal Regulations (annual edition) - October 1, 2006 Edition]
[Title 49 - TRANSPORTATION]
[Subtitle B - Other Regulations Relating to Transportation (Continued)]
[Chapter II - FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF]
[Part 232 - BRAKE SYSTEM SAFETY STANDARDS for FREIGHT and OTHER NON-]
[Subpart B - General Requirements]
[Sec. 232.103 - General requirements for all train brake systems.]
[From the U.S. Government Publishing Office]


49TRANSPORTATION42006-10-012006-10-01falseGeneral requirements for all train brake systems.232.103Sec. 232.103TRANSPORTATIONOther Regulations Relating to Transportation (Continued)FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OFBRAKE SYSTEM SAFETY STANDARDS for FREIGHT and OTHER NON-General Requirements
Sec. 232.103  General requirements for all train brake systems.

    (a) The primary brake system of a train shall be capable of stopping 
the train with a service application from its maximum operating speed 
within the signal spacing existing on the track over which the train is 
operating.
    (b) If the integrity of the train line of a train brake system is 
broken, the train shall be stopped. If a train line uses other than 
solely pneumatic technology, the integrity of the train line shall be 
monitored by the brake control system.
    (c) A train brake system shall respond as intended to signals from 
the train line.
    (d) One hundred percent of the brakes on a train shall be effective 
and operative brakes prior to use or departure from any location where a 
Class I brake test is required to be performed on the train pursuant to 
Sec. 232.205.
    (e) A train shall not move if less than 85 percent of the cars in 
that train have operative and effective brakes.
    (f) Each car in a train shall have its air brakes in effective 
operating condition unless the car is being moved for repairs in 
accordance with Sec. 232.15. The air brakes on a car are not in 
effective operating condition if its brakes are cut-out or otherwise 
inoperative or if the piston travel exceeds:
    (1) 10\1/2\ inches for cars equipped with nominal 12-inch stroke 
brake cylinders; or
    (2) The piston travel limits indicated on the stencil, sticker, or 
badge plate for the brake cylinder with which the car is equipped.
    (g) Except for cars equipped with nominal 12-inch stroke (8\1/2\ and 
10-inch diameters) brake cylinders, all cars shall have a legible decal, 
stencil, or sticker affixed to the car or shall be equipped with a badge 
plate displaying the permissible brake cylinder piston travel range for 
the car at Class I brake tests and the length at which the piston travel 
renders the brake ineffective, if different from Class I brake test 
limits. The decal, stencil, sticker, or badge plate shall be located so 
that it may be easily read and understood by a person positioned safely 
beside the car.
    (h) All equipment ordered on or after August 1, 2002, or placed in 
service for the first time on or after April 1, 2004, shall have train 
brake systems designed so that an inspector can observe from a safe 
position either the piston travel, an accurate indicator which shows 
piston travel, or any other means by which the brake system is actuated. 
The design shall not require the inspector to place himself or herself 
on, under, or between components of the equipment to observe brake 
actuation or release.
    (i) All trains shall be equipped with an emergency application 
feature that produces an irretrievable stop, using a brake rate 
consistent with prevailing adhesion, train safety, and brake system 
thermal capacity. An emergency application shall be available at all 
times, and shall be initiated by an unintentional parting of the train 
line or loss of train brake communication.
    (j) A railroad shall set the maximum main reservoir working 
pressure.
    (k) The maximum brake pipe pressure shall not be greater than 15 psi 
less than the air compressor governor starting or loading pressure.
    (l) Except as otherwise provided in this part, all equipment used in 
freight or other non-passenger trains shall, at a minimum, meet the 
Association of American Railroads (AAR) Standard S-469-47, ``Performance 
Specification for Freight Brakes,'' contained in the AAR Manual of 
Standards and Recommended Practices, Section E (April 1, 1999). The 
incorporation by reference of this AAR standard was approved by the 
Director of the Federal Register in accordance

[[Page 548]]

with 5 U.S.C. 552(a) and 1 CFR part 51. You may obtain a copy of the 
incorporated document from the Association of American Railroads, 50 F 
Street, NW, Washington, DC. 20001. You may inspect a copy of the 
document at the Federal Railroad Administration, Docket Clerk, 1120 
Vermont Avenue, NW, Suite 7000, Washington, DC or at the National 
Archives and Records Administration (NARA). For information on the 
availability of this material at NARA, call 202-741-6030, or go to: 
http://www.archives.gov/federal--register/code--of--federal--
regulations/ibr--locations.html.
    (m) If a train qualified by the Air Flow Method as provided for in 
subpart C of this part experiences a brake pipe air flow of greater than 
60 CFM or brake pipe gradient of greater than 15 psi while en route and 
the movable pointer does not return to those limits within a reasonable 
time, the train shall be stopped at the next available location and be 
inspected for leaks in the brake system.
    (n) Securement of unattended equipment. A train's air brake shall 
not be depended upon to hold equipment standing unattended on a grade 
(including a locomotive, a car, or a train whether or not locomotive is 
attached). For purposes of this section, ``unattended equipment'' means 
equipment left standing and unmanned in such a manner that the brake 
system of the equipment cannot be readily controlled by a qualified 
person. Unattended equipment shall be secured in accordance with the 
following requirements:
    (1) A sufficient number of hand brakes shall be applied to hold the 
equipment. Railroads shall develop and implement a process or procedure 
to verify that the applied hand brakes will sufficiently hold the 
equipment with the air brakes released.
    (2) Except for equipment connected to a source of compressed air 
(e.g., locomotive or ground air source), prior to leaving equipment 
unattended, the brake pipe shall be reduced to zero at a rate that is no 
less than a service rate reduction, and the brake pipe vented to 
atmosphere by leaving the angle cock in the open position on the first 
unit of the equipment left unattended.
    (3) Except for distributed power units, the following requirements 
apply to unattended locomotives:
    (i) All hand brakes shall be fully applied on all locomotives in the 
lead consist of an unattended train.
    (ii) All hand brakes shall be fully applied on all locomotives in an 
unattended locomotive consist outside of yard limits.
    (iii) At a minimum, the hand brake shall be fully applied on the 
lead locomotive in an unattended locomotive consist within yard limits.
    (iv) A railroad shall develop, adopt, and comply with procedures for 
securing any unattended locomotive required to have a hand brake applied 
pursuant to paragraph (n)(3)(i) through (n)(3)(iii) when the locomotive 
is not equipped with an operative hand brake.
    (4) A railroad shall adopt and comply with a process or procedures 
to verify that the applied hand brakes will sufficiently hold an 
unattended locomotive consist. A railroad shall also adopt and comply 
with instructions to address throttle position, status of the reverse 
lever, position of the generator field switch, status of the independent 
brakes, position of the isolation switch, and position of the automatic 
brake valve on all unattended locomotives. The procedures and 
instruction required in this paragraph shall take into account winter 
weather conditions as they relate to throttle position and reverser 
handle.
    (5) Any hand brakes applied to hold unattended equipment shall not 
be released until it is known that the air brake system is properly 
charged.
    (o) Air pressure regulating devices shall be adjusted for the 
following pressures:

------------------------------------------------------------------------
                       Locomotives                              PSI
------------------------------------------------------------------------
(1) Minimum brake pipe air pressure:
    Road Service........................................              90
    Switch Service......................................              60
(2) Minimum differential between brake pipe and main                  15
 reservoir air pressures, with brake valve in running
 position...............................................
(3) Safety valve for straight air brake.................           30-55

[[Page 549]]

 
(4) Safety valve for LT, ET, No. 8-EL, No. 14 EI, No. 6-           30-68
 DS, No. 6-BL and No. 6-SL equipment....................
(5) Safety valve for HSC and No. 24-RL equipment........           30-75
(6) Reducing valve for independent or straight air brake           30-50
(7) Self-lapping portion for electro-pneumatic brake                  50
 (minimum full application pressure)....................
(8) Self-lapping portion for independent air brake (full           30-50
 application pressure)..................................
(9) Reducing valve for high-speed brake (minimum).......              50
------------------------------------------------------------------------


[66 FR 4193, Jan. 17, 2001, as amended at 67 FR 17581, Apr. 10, 2002]