Authors: T.B. Sheridan (MIT), F.C. Gamst (U. of Mass - Boston), R.A. Harvey (BLE)

Date of Publication:  November 28, 1999

Sponsoring Agency:  U.S. Department of Transportation, Federal Railroad Administration, PTC Human Factors Team

Report No: STD-PTC-DEC-02-99

Abstract:

This document was requested by T. Raslear of the Federal Rail Administration (FRA) on 3/3/99 of the PTC Human Factors Team in conjunction with ongoing discussions of PTC standards. The charge was to investigate the "reliance effect" and the "distraction effect," where definition and focus were left to the authors.

With regard to future automation of railway systems, and in particular with regard to the implementation of Positive Train Control (PTC), questions have been raised about the possible propensity for a locomotive engineer (LE) or conductor (C) to become over-reliant on automation and/or to become distracted by the additional monitoring burdens required by the automation, and for these effects to compromise the performance of their duties and for safe and efficient train operation.

This white paper is organized by section as follows:

(1) First, details on the charge given to the authors by the FRA.

(2) Next, working definitions of terms "reliance effect" and "distraction effect" and the issues surrounding them.

(3) Review of the general human factors literature regarding humans and automation, and specifically the reliance and distraction phenomena -- for example in piloting aircraft, driving highway vehicles, operating nuclear power plants and performing routine machine operation tasks. For each of the reliance and distraction effects the relevance to PTC automation is discussed.

(4) Details of the relation of reliance and distraction to operations under PTC, along with implied recommendations. This section, the longest, reviews the "open system" nature of the rail transportation system, proposes a "human-centered" design philosophy for PTC, comments on the relevance of the UK's Great Western accident of 1997, discusses which kinds of distraction are particularly threatening, analyses the potential levels of automation for PTC design, and recommends which level seems best for safety.

(5) Classroom and simulator training for PTC.

(6) Conclusions.
 

No. of Pages:  20