Given the dynamic and complex nature of the construction industry, maintaining situation awareness at job sites is critical. To react properly, workers must identify dynamic safety hazards within the scene. The majority of studies assessing construction workers’ situation awareness have utilized static images, virtual reality, and other types of simulation methods, but questions remain as to whether these formats are able to capture and monitor workers’ naturalistic behaviors and hazard identification abilities. To identify whether the format of hazardous stimuli (i.e., static, image-based vs. dynamic, and video-based formats) impact workers’ subjective and objective hazard identification and situation awareness metrics, this study developed 23 safety hazard scenarios utilizing state-of-the-art augmented 360° panoramas and then tracked differences in workers’ visual search patterns and hazard identification abilities using eye-tracking technology. The workers’ cognitive responses, evidenced by their eye movements, showed that workers had significantly varied cognitive processes and abilities depending on the format of stimuli: Workers with lower hazard identification skills were more likely to miss hazards in a dynamic environment. This result suggests that the experimental setting should be carefully designed to determine construction workers’ natural cognitive process.
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Working-Memory Load as a Factor Determining the Safety Performance of Construction Workers
Cognitive processes have been found to contribute substantially to the human errors that lead to construction accidents. Working memory—a cognitive system with a limited capacity that is responsible for temporarily holding information available for processing—plays an important role in reasoning and decision-making. Since eye movements indicate where a worker directs his/her attention, tracking such movements provides a practical way to measure workers’ attention and comprehension of construction hazards. As a departure in construction industry research, this study correlates attentional allocation with working memory to assess workers’ situation awareness under different scenarios that expose workers to various hazards. To achieve this goal, this study merges research linking eye movements and workers’ attention with research focused on working-memory load and decision making and evaluates what, how, and where a worker distributes his/her attention while performing a task under different working-memory loads. Path analysis models then examined the direct and indirect effect of different working-memory loads on hazard identification performance. The independent variable (working-memory load) is linked to the dependent variable (hazard identification) through the set of mediators (attention metrics). The results showed that the high-memory load condition delayed workers’ hazard identification. The findings of this study emphasize the important role working memory plays in determining how and why workers in dynamic work environments fail to detect, comprehend, and/or respond to physical risks.
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- Award ID(s):
- 1824238
- NSF-PAR ID:
- 10144178
- Date Published:
- Journal Name:
- Construction Research Congress 2020
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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