Railroad Dispatchers Research Articles

A 24-hour lighting scheme to promote alertness and circadian entrainment in railroad dispatchers on rotating shifts: A field study

Shift-working railway personnel are highly susceptible to fatigue stemming from poor-quality sleep that can impair the performance of safety-critical functions. Disruption of the 24-h light–dark pattern incident on the retinae appears to play a central role in exacerbating these problems, especially with respect to exposure to light at night and circadian rhythms disruption. This field study tested and demonstrated the effectiveness and acceptability of an intervention (red and blue light combined with white light) to (1) promote circadian alignment, (2) advance the timing of dim light melatonin onset, (3) improve objective and subjective sleep quality, and (4) reduce subjective sleepiness in an operational context compared to a baseline (conventional lighting) condition. The lighting intervention promoted significantly greater synchrony between day-shift participants’ light–dark exposures and rest–activity patterns, but did not significantly advance the timing of dim light melatonin onset. The intervention was also associated with reduced objective sleep disturbances and improved (albeit less robustly) subjective sleep quality, but it only reduced participants’ subjective sleepiness while they were off duty during the day shift. This research demonstrates that lighting interventions can promote circadian alignment and improve sleep quality among railway shift workers and may be translatable to other 24-h industries.

Preliminary Analysis and Simulation of Railroad Dispatcher Workload

Railroad dispatch centers increasingly use technology to assist dispatchers as they interact with multiple entities across a variety of tasks to ensure trains and track personnel function safely on an efficient schedule. A railroad dispatcher workload simulation could, therefore, be useful in estimating the impact of new technologies on dispatchers’ workload and overall system performance, particularly in the concept generation phase of a systems engineering process. This paper first discusses railroad dispatchers’ work analysis based on a large dispatch center and then presents the development of the Railroad Dispatcher Workload Simulation (RDWS), which generates models of dispatcher workload given various settings.

Communication Strategies From High-reliability Organizations

Communication Strategies From High-reliability Organizations

Toward the Development of a Performance Model of Railroad Dispatching

Railroad dispatchers shoulder more responsibilities today than ever before due to changes in technology, operating practices and the economy. This paper reviews literature on the job of railroad dispatching and summarizes research conducted to identify and document railroad dispatcher tasks and activities. An initial set of dispatcher tasks was generated. Then two questionnaires were developed to expand the list, identify other factors that affect dispatcher taskload, and determine how challenging it is to collect data on these tasks. Questionnaires were sent to representatives from Federal Railroad Administration regional offices, railroad officers, and railroad dispatchers. Sixty-seven different dispatcher tasks were identified and organized into six top-level task categories. Questionnaire results suggest there is no single, efficient mechanism to collect dispatcher taskload data. The literature review and questionnaire data highlight the importance of the cognitive aspects of dispatching. Based on the results, a preliminary, but comprehensive, model of railroad dispatching performance is proposed.

Shared Situation Awareness as a Contributor to High Reliability Performance in Railroad Operations

Cooperative strategies of individuals within a distributed organization can contribute to increased efficiency of operations and safety. We examine these processes in the context of a particular work domain: railroad operations. Analyses revealed a variety of informal cooperative strategies that railroad workers have developed that span across multiple railroad crafts including roadway workers, train crews, and railroad dispatchers. These informal, proactive communications foster shared situation awareness across the distributed organization, facilitate work, and contribute to the overall efficiency, safety, and resilience to error of railroad operations. We discuss design implications for leveraging new digital technologies and location-finding systems to more effectively support these informal strategies, enhance shared situation awareness, and promote high reliability performance.

Fostering Shared Situation Awareness and on-Track Safety Across Distributed Teams in Railroad Operations

Cooperative strategies of individuals within a distributed organizational structure can contribute to increased efficiency of operations and safety. We describe selected results of a cognitive task analysis that examined the cognitive and collaborative demands and activities of railroad roadway workers. The findings highlight the informal cooperative strategies that railroad workers have developed across distributed teams consisting of roadway workers, train crews, and railroad dispatchers that foster shared situation awareness and enhance on-track safety. We discuss design implications for leveraging new digital technologies and location finding systems to more effectively support these informal strategies to improve efficiency and enhance on-track safety are discussed.

Development of a Minimum Set of Recommended Railroad Dispatcher Training Objectives: A Case Study

Two recent Federal Railroad Administration (FRA) safety audits found substantial variability in the way railroad dispatchers are trained. Given this variability, and the potential for compromised safety that arises, a need for more uniform dispatcher training exists. This paper discusses the development of a minimum set of railroad dispatcher training objectives that can be used by a wide variety of railroad operations, and are acceptable to all of the different stakeholders, including railroad management, railroad dispatchers, and the FRA. Using information from site visits, interviews, and existing training materials, a set of training objectives was developed using Bloom's taxonomy of cognitive learning outcomes. The objectives were reviewed by stakeholders to ensure that the objectives were broadly applicable and acceptable. The objectives can be used to develop instructional materials for any dispatcher training program. Lessons learned from this approach are discussed.

An Examination and Comparison of Workload and Subjective Measures Collected from Railroad Dispatchers

This study addresses whether subjective workload, stress and fatigue vary as a function of reported workload, time of day, and time on task for railroad dispatchers. Workload and subjective rating data were collected for two weeks at both a freight and a passenger dispatching facility. Results indicate that subjective fatigue is an amalgamation of time-on-task and time-of-day functions, though there appears to be a “rush hour” effect. Subjective stress and workload were mainly affected by reported workload and time-on-task. Number of trains handled was the more influential of the two reported workload measures.

Automatic dialing and electronic selection on railroad message and dispatcher circuits

Low-level tone-signal techniques are used for automatic calling and selection on multiparty single-line facilities. The subscribers, equipped with transistorized transmitters and receivers, transmit single tone signals for seizure, dialing, and release. These signals are propagated along the wires to the terminal equipment, where they are converted to d-c pulses and stored for interpretation. This interpretation is accomplished by relay logic in order to decide whether the call is for a party on the same line, or for a party within the PBX (Private Branch Exchange) to which the line is terminally connected. In the first case, the called number is converted into an amplitude-modulated tone, where the frequency of the carrier and the modulation correspond to the first and second significant digits dialed, respectively. This tone is then retransmitted for selection of the desired party. At the called subscriber's station, the electronic selector receiver, which takes the place of the electromechanical selector, responds only to the particular carrier corresponding to its number. In this receiver, the envelope is detected and the recovered modulation tone is amplified directly to drive one out of a maximum of five tuned ringers. A total of 60 stations can be used on one pair of wires having a maximum attenuation of 30 db (decibels).