[Federal Register Volume 72, Number 175 (Tuesday, September 11, 2007)]
[Notices]
[Pages 51896-51898]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E7-17800]


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DEPARTMENT OF TRANSPORTATION

Federal Railroad Administration


Electronic Remote Authority Delivery Systems

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

ACTION: Notice of interpretation.

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SUMMARY: FRA is issuing this notice of interpretation to inform 
interested parties of its position regarding the implementation of 
digital electronic remote authority delivery systems that permit 
authorized users to electronically request, obtain, and release 
authorities to occupy controlled tracks. These activities are 
classified as safety-critical functions, and may interact with the 
functions of train control systems and dispatching procedures. 
Depending on the functionality and complexity of these systems, 
railroads seeking to implement digital electronic remote authority 
systems may be required to comply with Title 49 of the Code of Federal 
Regulations (CFR) Part 236, Subpart H (Subpart H). This notice 
classifies digital electronic authority delivery systems based on their 
functionality and identifies categories of systems that are subject to 
compliance with the requirements of Subpart H.

ADDRESSES: You may submit comments to Thomas McFarlin, Staff Director, 
Signal and Train Control Division, or Olga Cataldi, Senior Electronic 
Engineer, FRA Office of Safety Assurance and Compliance, by facsimile 
(202-493-6216) or e-mail ([email protected]) or 
([email protected]). Comments may also be submitted to Kathy 
Shelton, FRA Office of Chief Counsel, by facsimile (202-493-6068) or e-
mail ([email protected]).

FOR FURTHER INFORMATION CONTACT: Thomas McFarlin, Staff Director, 
Signal and Train Control Division, Office of Safety Assurance and 
Compliance, FRA, 1120 Vermont Avenue, NW., Washington, DC, 20590 
(telephone: (202) 493-6203), e-mail ([email protected]); Olga 
Cataldi, Senior Electronic Engineer, Office of Safety Assurance and 
Compliance, FRA, 1120 Vermont Avenue, NW., Washington, DC, 20590 
(telephone: (202) 493-6321), e-mail ([email protected]); or Kathy 
Shelton, Office of Chief Counsel, FRA, 1120 Vermont Avenue, NW., 
Washington, DC 20590 (telephone: (202) 493-6063), e-mail 
([email protected]).

SUPPLEMENTARY INFORMATION:

Background

    With technical advances and the wide availability of wireless 
communication technology, a number of Class I and short line railroads 
have been developing and, for the past several years, implementing a 
variety of software-based applications for the electronic delivery of 
digital track authorities to roadway workers. Software-based digital 
communication between railroad workers and the dispatch center has 
proven to be an effective alternative to voice communication with the 
dispatcher via radio. Digital communications may potentially result in 
significant increases in safety by eliminating delivery or read back 
errors associated with voice communications. Digital communications may 
also increase the effectiveness of railroad operations and track 
maintenance resources utilization by significantly decreasing the time 
associated with obtaining and releasing track authorities. These 
potential operational and safety benefits are prompting railroads to 
extend the use of wireless data communication to digital transmission 
of track warrants to trains. Further, railroads are seeking to extend 
the functionalities associated with the digital communication of 
authorities to roadway workers and train crews to include the auto-
generation and issuance of authorities, excluding any involvement of 
the dispatcher.
    The regulations contained in 49 CFR Part 214, Subpart C, which 
currently govern the delivery of authorities for exclusive track 
occupancy to roadway workers, do not specifically address digital 
communication between the dispatcher and the employee in charge. 
Currently, 49 CFR 214.321(a)(1) requires that all authorities issued to 
a roadway worker in charge be given by the dispatcher or control 
operator who controls train movement on that track.
    The digital delivery of movement authorities to train crews is 
addressed in 49 CFR Part 236, Subpart H. This set of regulations 
prescribes the minimum safety standards for the development and 
operation of processor-based signal and train control systems. As 
stated in the preamble to Subpart H, FRA purposely left the term 
``train control'' undefined, as advances in technology supporting these 
systems would make any definition of the term ``train control'', or any 
list of train control systems and associated features, ``undoubtedly 
outdated'' in a relatively short period of time. See 70 FR 11052, 
11066. Therefore, the requirements contained in Subpart H apply to 
``safety-critical products'', which include systems that provide 
safety-relevant information on which crews are expected to rely. See 49 
CFR 236.901. However, FRA emphasized in the preamble to the rule that 
``[o]ther systems providing safety-relevant information on which crews 
are expected to rely will also fall within this term''. See 70 FR 
11052, 11066. In regard to dispatching systems, a centralized computer-
aided train dispatching system being a part of an ``office system'' may 
also be subject to Subpart H compliance, if ``it performs safety-
critical functions within, or affects the safety performance of, a new 
or next generation train control system.'' See 49 CFR 236.911(c).
    FRA recognizes that its current regulations do not clearly address 
the auto-generation and digital communication of authorities to roadway 
workers and locomotive engineers. FRA is currently taking measures to 
augment existing regulations to more clearly address these 
functionalities. For example, FRA, with the participation of the 
Railroad Safety Advisory Committee, has explored appropriate conditions 
for the digital transmission of authority to a roadway worker in 
charge. In light of these discussions, FRA expects to include specific 
concepts in a notice of proposed rulemaking for revision of 49 CFR Part 
214, Subpart C. Further, FRA has been in discussion with the 
Association of American Railroads regarding the need for general 
standards to ensure the effectiveness and security of wireless 
communications particularly

[[Page 51897]]

in the field of train control. Pending the issuance of regulations and 
other actions in this area, FRA believes that it is both necessary and 
appropriate to clarify the existing regulatory requirements applicable 
to the auto-generation and digital delivery of authorities. The 
following discussion is intended to provide that clarification.

Classification of Digital Electronic Remote Authority Delivery Systems

    Software-based digital electronic remote authority delivery systems 
can be classified based on their purpose, and the level of dispatcher 
involvement as follows:
    By purpose:
     Roadway Worker Protection (RWP) systems (deliver track 
occupancy authorities to a roadway worker in charge).
     Remote Authority systems (deliver track occupancy 
authorities to a roadway worker in charge and movement authorities to a 
train crew).
    By dispatcher's role:
     Dispatcher generated (or dispatcher confirmed) authorities
     Automatically generated authorities (these authorities may 
be generated by the system itself, by a computer-aided train 
dispatching system (CAD), or as part of a positive train control 
system).
    Remote Authority and Roadway Worker Protection systems can both be 
used in signaled and non-signaled (dark) territories. These systems can 
operate as either an autonomous dispatching-type system or as an 
overlay to an existing method of operation. Based on the classification 
given above, FRA has identified four distinct categories of digital 
electronic remote authority delivery system functionalities:
    1. Electronic transmission of authorities to roadway workers with 
dispatcher's electronic confirmation;
    2. Electronic transmission of authorities to train crews with 
dispatcher's electronic confirmation;
    3. Automatic generation and electronic transmission of the 
authorities to roadway workers without dispatcher's involvement; or,
    4. Automatic generation and electronic transmission of the 
authorities to train crews without dispatcher's involvement.
    While FRA fully supports the railroad industry's desire to 
implement digital electronic remote authority delivery systems, FRA 
also believes that to the extent such systems execute the necessary 
logic to generate valid mandatory directives or roadway work 
authorities, they are functionally forms of train control subject to 
Subpart H. Further, digital pathways embedded in conventional signal 
and train control systems, including communication-based train control 
systems, are relevant subsystems deserving of consideration within the 
context of Subpart H review. In the event of malfunction of any of 
these types of systems, FRA would expect each employing railroad to 
have operating rules in place that address reversion to voice or 
written delivery of authorities by the dispatcher, consistent with any 
applicable existing regulations.
    The following discussion provides clarification on the 
applicability of FRA regulatory requirements to each category of 
digital electronic remote authority delivery systems.

Systems Performing Electronic Transmission of Authorities to Roadway 
Workers With Dispatcher's Electronic Confirmation

    The software-based application (or processor-based system) belongs 
to this category if:
    1. It serves as an autonomous office (dispatching) system in the 
absence of a CAD system, or as an auxiliary system interfaced with an 
existing CAD system, and is used exclusively for issuing authorities to 
roadway workers to occupy controlled tracks;
    2. It allows the employee in charge to request, obtain, and release 
the authority to occupy a controlled track through wireless digital 
communication with the dispatcher or control operator in charge of the 
track;
    3. Upon receipt of an electronically transmitted request from a 
roadway worker to occupy track, the authority is generated by the 
dispatcher or automatically by the application system (or by CAD) and 
is electronically transmitted by the application system accompanied by 
electronic confirmation of the dispatcher;
    4. The dispatcher holds ultimate responsibility for the proper 
issuance of authority to roadway workers and for maintaining proper 
records of track occupancy by other authorized users; and,
    5. The system server retains electronic records of roadway workers' 
requests for authority and dispatcher's entries of all authority 
granted by the dispatcher, including those issued to trains.
    Such systems perform functions described in 49 CFR Part 214, 
although that part currently does not address means of authority 
delivery. These systems are not, however, subject to Subpart H because 
they only provide electronic transmission of track occupancy authority. 
The generation and release of the authority remains the responsibility 
of the dispatcher, as currently required by 49 CFR 214.321(a). Once the 
revision of Part 214 is completed, these systems may be subject to new 
requirements regarding electronic delivery of authorities to roadway 
workers in charge (related to security and authentication of the 
digital transmission).

Systems Performing Electronic Transmission of Authorities to Trains 
With Dispatcher's Electronic Confirmation

    The definition of this category of processor-based applications (or 
computer-based systems) coincides with the definition given above for 
RWP systems, except the delivery of authority is extended to trains.
    FRA has determined that the electronic delivery of movement 
authority to trains is a safety-critical function pertaining to train 
control systems. If the dispatcher is involved in the process of 
generating the authority or is confirming the CAD system-generated 
authority, and the closed-loop communication occurs between the 
dispatcher and train crew, FRA recognizes that the regulatory 
requirements for systems delivering authorities to trains should be the 
same as for those delivering authorities to roadway workers. FRA 
further recognizes that, if the system includes functions related to 
commanding or warning crews based on changing field conditions (e.g., 
in the same way a cab signal would ``drop'' if a circuit were 
deenergized by equipment rolling out on the main line), then the system 
is a train control application.
    FRA utilizes the following criteria in determining the 
applicability of Subpart H to systems of this category:
    1. If the content of electronic messages transmitted to a train 
crew are limited exclusively to movement authorities and other 
mandatory directives, the application system is exempt from compliance 
with Subpart H.
    2. If the content of electronic messages transmitted to a train 
crew, in addition to movement authorities and other mandatory 
directives, contain warning or other enforcement commands impacting 
train handling, the application system must comply with Subpart H.
    3. If the communication subsystem embedded in any new train control 
system is an integral part of that system, it is subject to Subpart H 
requirements.
    FRA encourages railroads to arrange digital systems which 
communicate safety-critical information so that security of the 
messages is maintained and authentication of those issuing and

[[Page 51898]]

acknowledging mandatory directives is established. Although use of 
digital transmission has the advantage of accuracy (avoidance of 
misunderstandings) and efficiency, insecure transmissions and lack of 
proper authentication could introduce new risks. FRA expects that, as 
this technology fully matures, industry standards will address these 
needs even more suitably than at present within an interoperable 
framework.
    If Subpart H is applicable, the railroad shall submit an RSPP and 
PSP required by 49 CFR 236.905 and 236.907.

Systems Performing Automatic Generation and Electronic Transmission of 
the Authorities to Roadway Workers Without Dispatcher's Involvement

    The processor-based application (or computer-based system) belongs 
to this category if:
    1. It serves as an autonomous office (dispatching) system, in the 
absence of a CAD system, or as an auxiliary system interfaced or 
integrated with an existing CAD system, and is used exclusively for 
issuing authorities to roadway workers to occupy controlled tracks;
    2. It allows the employee in charge to request, obtain, and release 
the authority to occupy a controlled track through wireless digital 
communication without the dispatcher's concurrence;
    3. Upon receipt of an electronically transmitted request from a 
roadway worker to occupy track, the authority is generated 
automatically by the CAD system (or application system) and is 
electronically transmitted by the application system without the 
dispatcher's concurrence; and
    4. The system server retains electronic records of roadway workers' 
requests for authority and all granted authorities, including those 
issued to trains.
    Such systems are subject to compliance with Subpart H. The delivery 
of track occupancy authority to roadway workers without the 
dispatcher's involvement is considered a safety-critical function in 
the same way that control of train movements is safety-critical. This 
constitutes a basis for these systems to comply with Subpart H 
requirements. Railroads shall submit an RSPP and PSP in accordance with 
49 CFR 236.905 and 236.907 prior to implementing any such system. 
Relief is also required from the requirements of Part 214, Subpart C, 
related to dispatcher involvement in the issuance of roadway work 
authorities.

Systems Performing Automatic Generation and Digital Transmission of 
Authorities to Trains Without Dispatcher's Involvement

    The definition of this category of processor-based applications (or 
computer-based systems) coincides with the definition given in a 
previous section for RWP systems, except that the delivery of 
authorities is extended to trains.
    Systems of this category are subject to compliance with Subpart H 
because the delivery of track occupancy authority to roadway workers 
and trains without dispatcher involvement is considered a safety-
critical function of a train control system. Therefore, railroads shall 
submit an RSPP and PSP in accordance with 49 CFR 236.905 and 236.907 
prior to implementing any such system.
    Those interested in implementing systems that automatically 
generate mandatory directives, roadway work authorities, or other 
instructions or commands (executed by persons or equipment) bearing 
directly on the safety of train operations, are respectfully referred 
to Appendix C of 49 CFR Part 236, which outlines safety assurance 
criteria and processes that are relevant to such an undertaking.
    FRA seeks comments on this notice from interested parties. Please 
refer to the Addresses section for additional information regarding the 
submission of comments.

    Issued in Washington, DC on September 4, 2007.
Jo Strang,
Associate Administrator for Safety.
[FR Doc. E7-17800 Filed 9-10-07; 8:45 am]
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