## 2 Research Background  
### Construction Worker Hazard Recognition and Risk Perception  
The hazard recognition and risk perception of workers are essential for safety in construction work environments, but unfortunately, recent studies showed that many construction hazards are not recognized by the workers, leading to accidents and injuries [17]. Furthermore, many previous studies indicated that workers frequently underestimate the safety risks [17]. Researchers found that among the many reasons for such missed hazard recognition or underestimated risks are safety knowledge [18], distraction [17], training [2], blind spots [19], the emotional states of the workers [20], and the organizational safety climate [21].  
Researchers have found that situation awareness (SA) is a useful theoretical framework for understanding how a construction worker recognizes a hazard within a work environment and the factors involved with the process of risk perception [11; 19]. SA is a comprehensive term denoting the perception of the elements in a constrained environment and consists of three dimensions: \"a constrained time and space, the comprehension of the meaning, and the projection of their status in the near future.\" [22]. [PERSON] [23] viewed situation awareness as part of a person's state of knowledge related to perceiving risks and making decisions in a dynamic environment. To achieve good SA, the first step is to perceive the details of the relevant elements. The second step is to comprehend the perceived information and its meaning in the given environment. The third step is to project future events and possibilities to make a decision for an action that is most appropriate in the given situation [24]. This process of situation awareness is influenced by internal and external factors, including the individual's ability to recognize and comprehend an observed situation and previous experience and mental models [24].  
It is difficult for workers to keep aware of all hazards in the surrounding environment during work. [PERSON] [25] developed an accident causal process model showing that incomplete cognition of hazards can cause multiple human errors. Previous research revealed that keeping good SA is even harder for people who work in a dynamic and less organized environment, such as military, construction, and road environments [26; 27; 28]. [PERSON] et al. [29] identified some implications of the theory of SA regarding the use of road environments and explained accident causation based on the theory. In the context of construction works, the theory of SA explains why workers' correct and timely recognition of hazards is critical for safety. Such criticality has already resonated among several researchers in the construction domain, who have investigated how technology can assist workers with maintaining good SA. For example, [PERSON] et al. [30] integrated a Differential Global Positioning System (DGPS) and wireless and web-based technologies into construction equipment to track mobile targets and inform workers when they are approaching. Their research revealed that various technologies can be used to define, detect, and evaluate the SA performance of workers and supervisors. [PERSON] et al. [31] conducted a virtual reality-based experiment to evaluate the SA of workers in a simulated environment and proved that eye-tracking technology is a practical way to examine the level of SA. Additionally, [PERSON] et al. [32] investigated construction workers' SA in dynamic construction work environments using eye-tracking devices.