Iranian Journal of Ergonomics

Introduction: One of the most important subjects in the analysis of driver’s behavior had been situation awareness during the past decade. However, no study has been investigated the relation among component of situation awareness and performance and cognitive abilities of bus drivers. Current study aimed to survey relationship between bus drivers’ situation awareness, driving performance and cognitive abilities using driving simulator.

Material and Methods: In this study, 30 professional bus drivers who have diploma or higher degree participated. Situation awareness measured by SAGAT technique and tests UFOV, EFT and WMS were used for measuring of cognitive abilities. Brake reaction time and lane departures were criteria for driving performance.

Results: Accordingly, the result showed significant relation between drivers’ situation awareness before and after hazard conditions. Among WMS, divided attention, selective attention and EFT with level 1 of situation awareness was seen significant relation. The result of current study released a significant correlation among WMS and divided attention with lane departure.

Conclusion: Results showed, in general, the driver's situational awareness in dangerous conditions increases. The study showed that cognitive ability affects only level 1 of situational awareness. According to role of situational awareness in driving performance, the results of lane keeping showed that perception might be a key factor in driving performance.

Introduction: Studies have shown that one of the factors affecting occupational injuries is employees’ awareness of work situation. Therefore, it is important to identify factors affecting situational awareness. The aim of this study was to investigate the role of fatigue and cognitive failures in predicting work situation awareness among employees.

Methods: This study was a cross-sectional study with a descriptive-correlational design. The sample consisted of 154 employees of the Tehran Pars Khodro Company in 2015, who was selected by stratified random sampling method and responded to questionnaires of fatigue from Chalder et al. (1993), cognitive failures from Broadbent et al. (1982) and work situation awareness of Sneddon et al. (2006). Data were analyzed using Pearson correlation coefficient and stepwise regression analysis.

Results: The results showed that there were significant relationships between fatigue, cognitive failures and work situation awareness (P < 0.01). Also, fatigue and cognitive failures predicted almost 14% and 25% of the variance of work situation awareness among employees, respectively (P < 0.05).

Conclusions: The reduction of employees’ cognitive and emotional capacity could reduce their awareness of work situation.