A Comparative Analysis of Mental Workload between Train and Bus Drivers

Soewardi, Hartomo; Putra, Perdana Suteja · 2018 · Crossref

DOI: 10.1051/matecconf/201815902076

archive: archived pipeline: cataloged verified

Get this paper ↗ (DOI — opens at the source; we link to it, we don't host it)

Summary

This study addresses the critical issue of human error in public transportation, which frequently leads to accidents, delays, and passenger apprehension. Motivated by high accident rates in Indonesian train and bus systems, the research aims to compare the mental workload of bus drivers and train machinists. While previous studies often relied solely on subjective assessments, this work integrates both subjective and objective criteria to provide a more comprehensive evaluation of driver stress and workload. The methodology involved thirty participants: fifteen bus drivers and fifteen train machinists, all with over three years of experience working the Yogyakarta-Jakarta route. Mental workload was assessed using two primary measures. Objectively, Salivary Alpha-Amylase (SAA) levels were measured before and after driving using disposable test strips and a Cocorometer, with values above 45 kU/l indicating moderate stress and above 60 kU/l indicating high stress. Subjectively, the NASA-Task Load Index (NASA-TLX) questionnaire was administered after each trip to evaluate six dimensions: mental demand, physical demand, temporal demand, effort, own performance, and frustration. Statistical analysis employed non-parametric Wilcoxon Signed-Rank tests to compare pre- and post-driving SAA levels within groups, and Mann-Whitney U tests to compare differences between bus drivers and machinists. The results indicate that both groups experienced high stress levels, but bus drivers exhibited significantly higher objective stress markers. Bus drivers’ mean SAA levels were 91.99 kU/l before driving and 83.19 kU/l after, compared to 70.33 kU/l and 72.28 kU/l for machinists, respectively. These differences were statistically significant (Asymp. Sig. 0.049). Subjectively, bus drivers reported a higher weighted workload score (1051) than machinists (1031), though this difference was not statistically significant (Asymp. Sig. 0.561). Detailed analysis revealed that bus drivers faced higher demands in temporal, physical, and mental categories due to traffic uncertainty and complex decision-making. Conversely, machinists reported higher frustration levels, attributed to strict operational procedures and communication pressures. The study concludes that bus drivers endure a higher mental workload than train machinists, a finding supported significantly by objective physiological data and supported by subjective self-reports. The higher stress in bus drivers is linked to environmental uncertainties such as traffic jams and the need for constant improvisation, whereas machinists’ stress stems from rigid procedural compliance. These findings suggest that interventions to reduce human error should prioritize strategies to mitigate the specific cognitive and physiological demands placed on bus drivers, such as improved scheduling or traffic management support.

Provenance

The full processing record for this entry. Every stage of this paper's journey through the pipeline is logged — what ran, with which tool and model, how many attempts it took, and when it last completed.

Summary generated by qwen3.6-27b-nvidia on 2026-08-10; verification: verified.

Topics

Ranked by relevance to this paper. Hover a topic for its definition.

• stress driving
• mental demand
• workload measurement
• truck driver fatigue

Information type

What kind of knowledge this paper contributes, grouped by family — independent of topic (what it is about) and method (how it was studied).

• Empirical Findings: physiological data, self report data
• Theoretical Contribution: theory or model