49 C.F.R. § 232.103 General requirements for all train brake systems.
Title 49 - Transportation
(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 §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 §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 (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 (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 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: [66 FR 4193, Jan. 17, 2001, as amended at 67 FR 17581, Apr. 10, 2002]
Title 49: Transportation
PART 232—BRAKE SYSTEM SAFETY STANDARDS for FREIGHT and OTHER NON-PASSENGER TRAINS and EQUIPMENT; END-of-TRAIN DEVICES
Subpart B—General Requirements
§ 232.103 General requirements for all train brake systems.
------------------------------------------------------------------------ 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(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------------------------------------------------------------------------
