Technical Reports

Human Factors Considerations in the Evaluation of Processor-Based Signal and Train Control Systems

  • 01
  • Jun
  • 2007
AUTHOR: John Wreathall, Emilie Roth, Dennis Bley, and Jordan Multer
SUBJECT: Human Factors
KEYWORDS: Cognitive task analysis, communications, decisionmaking, human factors, human reliability
ABSTRACT: In August 2001, the Federal Railroad Administration issued the notice of proposed rulemaking: Standards for Development and Use of Processor-Based Signal and Train Control Systems (49 Code of Federal Regulations Part 236). This proposed rule addresses the design and implementation of processor-based train control systems. Under the proposed rule, a railroad wishing to implement a positive train control (PTC) system in revenue service must develop and submit a product safety plan (PSP) and assess the risk associated with the new system. This report attempts to fill the gap provided by the lack of knowledge about the kinds of human performance challenges and safety risks that will occur with these proposed systems. To fill this gap, the authors identified human factors issues that arose in other industries where similar kinds of technology and human-machine interfaces were used. This literature review, along with an analysis of PTC-preventable accidents, served as the basis for structuring interviews with employees at several railroads that had experience with train control technology containing elements of PTC. The answers to these questions provide the reader with a roadmap of human performance issues to consider in preparing or evaluating a PSP, along with the implications for risk.