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Proposed Rule

Electronically Controlled Pneumatic Brake Systems

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Information about this document as published in the Federal Register.

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Federal Railroad Administration (FRA), Department of Transportation (DOT).


Proposed rule; partial reopening of comment period.

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This document announces an additional 15-day period to file comments in this proceeding. This extension provides interested parties an opportunity to comment on recently revised or new standards developed by the Association of American Railroads (AAR) that are related to the notice of proposed rulemaking (NPRM) in this proceeding.


Written comments must be received by May 5, 2008. Comments received after that date will be considered to the extent possible without incurring additional expenses or delays.


Comments: Comments related to Docket No. FRA-2006-26175, may be submitted by any of the following methods:

1. Web site: Comments should be filed at the Federal eRulemaking Portal, Follow the Web site's online instructions for submitting comments.

2. Fax: 202-493-2251.

3. Mail: Docket Management Facility, U.S. Department of Transportation, 1200 New Jersey Avenue, SE., W12-140, Washington, DC 20590.

4. Hand Delivery: Room W12-140 on the Ground level of the West Building, 1200 New Jersey Avenue, SE., Washington, DC between 9 a.m. and 5 p.m. Monday through Friday, except Federal holidays.

Instructions: All submissions must include the agency name and docket number or Regulatory Identification Number (RIN) for this rulemaking. Note that all comments received will be posted without change to including any personal information. Please see the Privacy Act heading in the SUPPLEMENTARY INFORMATION section of this document for Privacy Act information related to any submitted comments or materials.

Docket: For access to the docket to read background documents or comments received, go to or to Room W12-140 on the Ground level of the West Building, 1200 New Jersey Avenue, SE., Washington, DC between 9 a.m. and 5 p.m. Monday through Friday, except Federal holidays.

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James Wilson, Office of Safety Assurance and Compliance, Motive Power and Equipment Division, RRS-14, Mail Stop 25, Federal Railroad Administration, 1200 New Jersey Avenue, SE., Washington, DC 20590 (telephone 202-493-6259); or Jason Schlosberg, Trial Attorney, Office of Chief Counsel, Mail Stop 10, Federal Railroad Administration, 1200 New Jersey Avenue, SE., Washington, DC 20590 (telephone 202-493-6032).

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I. Background

On September 4, 2007, FRA published in the Federal Register an NPRM seeking comments on proposed rules relating to the implementation and use of electronically controlled pneumatic (ECP) brake systems on freight trains and freight cars. See 72 FR 50820. The NPRM proposed incorporation by reference of existing AAR Standards and Recommended Practices related to ECP brake systems. At the time FRA published the NPRM, those standards, collectively known as the AAR S-4200 Series Standards, included the following:

(1) AAR S-4200, ECP Cable-Based Brake Systems—Performance Requirements (2004);

(2) AAR S-4210, ECP Cable-Based Brake System Cable, Connectors, and Junction Boxes—Performance Specifications (2002);

(3) AAR S-4220, ECP Cable-Based Brake DC Power Supply—Performance Specification (2002);

(4) AAR S-4230, Intratrain Communication (ITC) Specification for Cable-Based Freight Train Control System (2004);

(5) AAR S-4250, Performance Requirements for ITC Controlled Cable-Based Distributed Power Systems (2004); and

(6) AAR S-4260, ECP Brake and Wire Distributed Power Interoperability Test Procedures (2007).

In the NPRM, FRA noted that the AAR S-4200 Series do not provide requirements for hardware and software configuration management plans and acknowledged that AAR was in the process of developing standards related to ECP brake system configuration management. The NPRM further noted that if a configuration management standard were to be adopted and published by the AAR subsequent to the closing of the NPRM's comment period, FRA would consider other forums for receiving comments, including, but not limited to, issuing a supplemental notice informing interested parties of the standard's availability.

Subsequent to the closing of the comment period in this proceeding, AAR made changes to the S-4200 Series Standards by modifying individual standards S-4200 and S-4210 and by proposing a new standard S-4270. FRA has preliminarily reviewed these changes and notes that they are in each case either (i) more protective of safety or (ii) safety neutral but designed to make ECP brake systems more practical for field application. Accordingly, FRA presents the proposed changes for comment with a view toward potential incorporation in the final rule.

After a period for comment by AAR members, AAR published a revised S-4200 standard and postponed the implementation date from February 16, 2008, to June 1, 2008. See AAR Circular Letters C-10686 and C-10697; AAR Standard S-4200 (2008). AAR Circular Letter C-10686 summarized the changes to the S-4200 standard as follows:

Section Description of Setup: This section was revised to limit changes of the empty/load setting to changes of E/L from empty to loaded only.

Section Empty/Load: A sentence was added to stipulate that the engineer shall not be allowed to change the train's empty/load setting from loaded to empty while the train is in motion.

Section Empty Load Selection While the Train is Enroute: A sentence was revised to require that the train be stopped with a full service brake application or a full service brake application must have been commanded for at least 2 minutes in order to change the train's empty/load setting from loaded to empty.

Section Train Net Braking Ratio: This section was revised to require that, if the OEM provides the optional ability to change the train NBR, the engineer will not be given the opportunity to change the setting.

Section Configuration Confirmation: Empty/load value was added to brake pipe pressure setpoint for which the HEU shall display the entered values and request a confirmation from the engineer.

Section 4.3.12 Mechanical Brake Cylinder and Reservoir Venting: This section was revised to require a means to manually vent pressure from the brake cylinder and reservoir at every CCD location from both sides of the car without reliance on electronic activation or control.

Note 1 has been revised to require that the brake cylinder release valve be capable of releasing air pressure from all brake cylinders; regardless of the charge status of the brake pipe.

Note 3 is new.

Note 4 is old Note 3 revised.

Note 6 is old Note 7 revised.

Note 7 is new (pneumatic backup functionality when brake cylinder release valve has been activated)

Section Recovering from a Missed EOT Beacon Fault: A sentence has been added requiring re-initialization of the train if the EOT beacon is lost for more than 15 seconds while in RUN mode.

Section 4.4.16 Recovery from Emergency, Fault-Induced, or Penalty Brake Applications: When recovering from an emergency brake application, the operator will position the brake lever to 100% brake application to release the interlock.

Section 6.0 Approval Procedure: This detailed section has been replaced with a cross reference to AAR Standard S-4240 (adopted January 16, 2007, Circular Letter c-10454).

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After a period for comment by AAR members, AAR also issued revisions to its S-4210 standard. See AAR Circular Letter C-10650; AAR Standard S-4210 (2007). While the standard was apparently implemented in November 2007, its accompanying AAR Circular Letter C-10650 was issued on December 6, 2007. AAR Circular Letter C-10650 summarized the changes to the S-4210 standard as follows:

Section 3.1 General Characteristics: The overall outside dimension of the cable was changed from 0.70 inch minimum/0.75 inch maximum to 0.675 inch minimum/0.725 inch maximum.

Section 6.0 CONNECTOR ASSEMBLIES: This revised section covers the intercar connector, cable, strength member (lanyard), and car body junction box plug connector.

Section 7.0 INTERCAR CONNECTOR PERFORMANCE AND TESTING DESCRIPTIONS: This section has been significantly expanded.

Section 8.0 This is a new section with a TESTING SEQUENCE:

Section 9.0 CAR BODY CONNECTIONS: The car body connector mounting envelope has been clarified and expanded with a figure added. Figures for the various end air hose mounting arrangements and brackets have been added. The length of the entire connector assembly would be revised to 36 inches + or − 1 inch for conventional cars versus 40 inches now.

AAR has also proposed a new standard S-4270 to address ECP brake system configuration management plans. According to AAR Circular Letter C-10750, this specification describes how the industry will control and track hardware and software changes to the ECP equipped interchange car fleet. AAR is currently seeking comment on proposed standard S-4270.

To ensure that the final rule in this proceeding does not rely on outdated information or technical standards, FRA is proposing to replace the NPRM's references to S-4200 and S-4210 with the aforementioned updated versions of those standards. Parties may be reluctant to adopt technology whose standards may be soon outdated or obsolete. Thus, implementation of a final rule relying on outdated standards or procedures may further delay the proliferation, implementation, and use of ECP brake systems.

For these same reasons, FRA also seeks comments on the proposed draft standard S-4270. In the NPRM, FRA proposed the incorporation by reference of standard S-4270 if the standard was adopted by AAR prior to the date necessary for its inclusion in the final rule. However, FRA will not include S-4270 in the final rule if substantial changes are made from the current draft or AAR's adoption of S-4270 is not complete in the near future.

Accordingly, FRA is hereby reopening and extending the comment period in this proceeding for an additional 15 days from the date of this notice. During this additional comment period, FRA is seeking comments solely on the updated versions of S-4200 and S-4210 and the new standard S-4270, subject to the caveats explained above. FRA will not consider comments relating to any issues outside of this narrow scope. FRA has placed the revised and new standards and their concomitant circular letters referenced herein in the public docket to this proceeding.

Privacy Act

Anyone is able to search the electronic form of any written communications and comments received into any of our dockets by the name of the individual submitting the document (or signing the document, if submitted on behalf of an association, business, labor union, etc.). You may review DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477) or at​privacy.html.

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Issued in Washington, DC, on April 14, 2008.

Grady C. Cothen, Jr.,

Deputy Associate Administrator for Safety Standards and Program Development.

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[FR Doc. E8-8432 Filed 4-17-08; 8:45 am]