## 2 Literature Review  
Many researchers have reviewed the use of AR in the construction industry. These studies have explored the implementation of AR for specific uses, such as design review [6], exchange of information methods [15], construction inspections and monitoring applications [16; 17], construction layout tasks [18], and construction activity visualization [19].  
In order to understand the trends reported in previous studies among the different uses of AR, several studies have explored the state of knowledge around AR. For example, a critical review of academic publications that investigated how learning is different between AR and non-AR experience was conducted to provide a comprehensive understanding of how the medium of AR differs from other educational media [20]. [PERSON] et al. (2013) discussed trends in AR applications for architecture, engineering, construction, and facility management (AEC/FM) by summarizing the results of 101 research efforts, and they outlined the research trends and opportunities for applying AR focusing on four technologies, i.e., localization, natural user interface (NUI), cloud computing, and mobile devices [21]. An AR literature study has also been conducted to provide a statistical review of the use of AR in the AEC industry offering construction practitioners and researchers an assessment of AR application including the purposes for which these technologies have been applied in different project phases from 1999 to 2012 [22]. In addition, [PERSON] et al. (2021) investigated the most common limitations and benefits reported by construction-related research publications using current generation AR technology [12]. Moreover, a meta-analysis of AR challenges in the underground utility construction industry was conducted by [PERSON] et al. (2018) that aimed to make the construction industry aware of the benefits of leveraging AR to prevent utility strikes, while enhancing productivity [23]. In 2020, [PERSON] et al. conducted a systematic review of AR applications in the industry to better understand the state-of-the-art of this technology in the underground construction field, and to identify challenges and barriers [24].  
While these studies delved into the implementation of AR in the industry and the reported patterns, their focus may not have necessarily been on real-time, synchronous usage of AR in the field. This emphasizes the importance of gaining a deeper understanding of the influential factors that specifically impact AR applications in the construction industry, particularly in the context of synchronized communication.  
Given the novelty of AR and the practical implications from testing unproven technologies on site, it seems logical that the majority of studies would focus on lab-based environments to test various aspects of AR prior to practical implementation. However, after testing AR in a controlled environment, several studies expressed the importance of AR testing on uncontrolled live construction sites where user performance was affected by site conditions such as noise, labor congestion, and safety concerns [18]. Testing the application in a real environment helps to evaluate the flexibility of AR leading to real improvements in performance and productivity. [PERSON] and [PERSON] (2018) mentioned that the performance of the user was affected by site conditions [18]. [PERSON] et al. (2014) stated that investigating the development factors of 3D perception using AR in a construction context would be more valuable [25]. Similarly, some studies have encouraged the need for future studies to be conducted on construction sites [21]. The high percentage of AR studies conducted in controlled environments highlights the need to build on the findings of these studies and to explore AR research in uncontrolled environments in the construction industry. This highlights the necessity of comprehending the various types of environmentsand contextual factors that can impact the implementation of AR for communication in the construction industry.