Construction is a high-hazard industry encompassing a wide array of activities. The construction phase is particularly prone to accidents compared to other project stages. This heightened risk stems from the inherent complexity of construction projects, which often unfold in uncontrolled, unprepared, and dynamic environments. Each project progresses through multiple phases before completion, leading to continuous changes in workplaces, occupancy levels, available space, and viable evacuation routes [1–2] Furthermore, evacuation conditions during construction differ significantly from those in later phases. The potential for diverse and unpredictable disasters [3] makes pre-determining the most appropriate evacuation routes challenging. To compound these challenges, the prevailing communication systems on many construction sites are non-interactive, hindering effective communication between owners, contractors, consultants, and other stakeholders during emergencies. This inability to directly and promptly disseminate critical evacuation information can result in injuries and fatalities.

The construction project is a fragmented and dynamic sector with a project-based nature, as shown in Fig. 1. This means that many stakeholders operate in frequently changing relationships [4]. An essential key to an effective emergency response is a communication system that can relay accurate information quickly. Information should exist only once to achieve effective and reliable communication rather than being duplicated unnecessarily. Therefore, communications equipment must be utilized, procedures developed, and personnel trained. In contrast, the prevailing communication system in the construction industry is characterized by a non-interactive model among stakeholders, including owners, contractors, consultants, and other involved parties. This system primarily relies on traditional methods such as email, CAD drawings, phone calls, WhatsApp, and in-person site meetings. OSHA statistics [5] underscore that diverse emergencies, encompassing severe weather events, earthquakes, and structural failures, can necessitate rapid evacuation within construction projects. Therefore, ensuring the robustness of evacuation plans to accommodate such unforeseen events becomes paramount. Furthermore, existing communication systems frequently centralize safety monitoring and control responsibilities with a single entity. This approach proves inadequate in addressing the dynamic nature of construction projects, failing to furnish the necessary information to meet daily evacuation requirements. Consequently, current practices necessitate a paradigm shift towards enhanced information accessibility and facilitated interactive communication among all project stakeholders.

Current practices within the construction industry often exhibit a disconnect between static fire exit signage and evacuation routes and the dynamic nature of construction environments [4]. This necessitates reliance on worker experience and intuition for navigating the evolving workplace, which can increase risk, particularly for new personnel unfamiliar with the project layout. Activities such as material handling and obstructing pathways further amplify this vulnerability. Such reliance on individual judgment in the face of shifting conditions poses a significant challenge to effective emergency evacuation procedures. While the construction industry adheres to site-specific fire safety planning practices that should be reviewed and updated regularly [5], the current evacuation plans are often not updated in line with the construction work schedule and environment. An abnormal event can result in situations, as shown in Fig. 2, where individuals become trapped by materials and equipment during a fire, contributing to high fatalities in construction site fires. In addition, this information is adapted from the author's doctoral thesis data presented [6], this study aims to develop a communication system that supports evacuation routes in a dynamic nature, which is a system that would generate appropriate evacuation routes for construction workers and staff in construction projects.

This research endeavors to develop an innovative safety management system specifically designed to accommodate the inherent dynamism of construction projects. Recognizing the direct influence construction activities exert on evacuation routes and work schedules, which can impact evacuation performance, this system integrates visualization technologies informed by the literature, as mentioned in a literature review. According to the field observations, they were conducted at high-rise building construction projects. These observations comprised comprehensive walk-in surveys to capture a holistic overview of safety management practices at each project. Aspects such as established evacuation routes, fire emergency procedures, and the current implementation status of these measures were meticulously documented. Photographic and video documentation were employed to supplement these observations. It is noteworthy that, during the surveys, emergency procedures like evacuation routes depicted in construction drawings and fire exit signs were consistently observed across all sample construction projects, as shown in Fig. 4 to Fig. 5

Despite regulatory requirements for precise and readily visible exit signage, many construction projects fall short of compliance. Inadequate placement, insufficient lighting, and a failure to update signage to reflect changes in the construction environments can create confusion and hinder effective evacuation during emergencies. The dynamic nature of construction sites exacerbates this challenge. Daily shifts in work areas, personnel, and routes can lead to unfamiliarity with evacuation plans, particularly for new workers. Under the time pressure of an emergency, this unfamiliarity can increase the likelihood of errors in judgment and delays in evacuation, potentially resulting in severe consequences. Findings from construction site surveys have highlighted several critical factors contributing to injuries and fatalities arising from accidents within construction projects:

These findings emphasize the need to enhance safety communication protocols and elevate the efficacy of evacuation planning within the construction industry. Moreover, on-site assessments underscored the limitations of existing fire emergency procedures. Two-dimensional (2-D) fire evacuation plans were found to lack clarity and often remained static, failing to reflect the dynamic nature of construction sites. The absence of clear and strategically placed fire exit signs, compounded by the presence of unclear or outdated signage, further amplifies the risk of confusion and delays during evacuations. The constantly changing work areas and routes inherent to construction environments underscore the need for an adaptive fire evacuation system. Developing a novel fire evacuation route system capable of dynamically responding to the evolving construction landscape is proposed to address these critical concerns. This system would seamlessly integrate with construction schedules, ensuring evacuation routes are updated in real-time to reflect current site conditions. By automating the generation of appropriate evacuation routes, the system would proactively address the issue of inadequate fire evacuation guidance. This powerful decision-making tool would significantly enhance safety by providing construction workers and staff with clear and readily understandable evacuation information, mitigating potential hazards during fire emergencies.

The Self Care using Technology Evacuation System (SCT Evacuation System) is a marker-based Augmented Reality (AR) application that leverages Building Information Modeling (BIM) and specialized coding to furnish real-time guidance and information to construction personnel during emergencies. The system facilitates safe evacuation from hazardous locations and offers dynamic material handling route guidance that adapts to the evolving construction environments. During the initial setup, as shown in Fig. 7, the system prompts users to input their current workday, name, and surnames, enabling personalized identification and tracking. This information is displayed within the system, as shown in Fig. 8. Developed in response to on-site observations, the SCT Evacuation System comprises three cores’ components: BIM authoring, marker-based location, and application authoring. The system addresses the challenges posed by the dynamic nature of construction sites, where obstructions and changes in layout are commonplace, particularly during emergencies. By automating the generation of contextually relevant evacuation routes and providing clear, real-time guidance, the SCT Evacuation System is a powerful decision-making tool, empowering construction workers and staff to navigate safely and efficiently during critical situations. The system's intuitive user interface, as shown in Fig. 9, further enhances its usability and effectiveness in promoting a safer construction environment.

The development of the Self Care using Technology Evacuation System (SCT Evacuation System) aimed to furnish construction workers and staff with essential evacuation information and route guidance. Comprising three distinct modules: BIM authoring, marker-based location, and application authoring, the prototype system leverages marker- based Augmented Reality (AR) technology and integrates Building Information Modeling (BIM) alongside specialized coding to provide real-time, visually enhanced guidance during emergencies. Each module within the system boasts unique preparation, input, process, and output components, generating diverse data streams that collectively contribute to the proposed system's visualization capabilities. This holistic approach to safety management empowers construction personnel with invaluable real-time information and decision- making support during evacuation scenarios.

The proposed system delivers crucial information, including the user's precise location, facilitating accurate distance-to-exit calculations. It further enhances evacuation guidance through voice and arrow directions, a virtual green line delineating the evacuation path, clear identification of exits, and dynamic distance updates. User identification functionality and the capacity to adapt evacuation routes to encounter obstacles further bolster the system's efficacy and adaptability.

The proposed system incorporates many functionalities, notably calculating and presenting the shortest evacuation route from the user's current position to the nearest exit, accompanied by a visually intuitive virtual green line for guidance. These functionalities underwent rigorous testing in both simulated and real-world environments to ensure the system's accuracy and reliability. During testing, the potential impact of weak internet connectivity on system performance was identified and mitigated through a personal hotspot. This comprehensive testing approach validated the system's efficacy in providing precise and practical evacuation guidance, even under challenging network conditions.

The feasibility of deploying the proposed communication system within real-world construction environments was rigorously evaluated based on empirical data from virtual and real-world testing scenarios. The system's principal strength resides in its strategic integration of visualization technologies, such as BIM and AR, to facilitate the provision of dynamic evacuation routes and material handling guidance, adeptly accommodating the ever-evolving nature of construction projects. This capability proves particularly beneficial in aiding decision-making for personnel unfamiliar with the intricacies of the project layout. However, the system's practical implementation is contingent upon the meticulous execution of the BIM authoring process, which necessitates accurate as-built drawings for precise spatial positioning and exit information, forming the foundation for a robust virtual model. The marker-based location functionality bridges the gap between the physical and virtual realms, dynamically identifying user locations and generating contextually relevant evacuation routes. Nevertheless, it is essential to acknowledge certain limitations inherent to the system. Its operational effectiveness is predicated on the availability of markers and a stable internet connection. While using CCTV cameras presents a potential avenue for circumventing these limitations through user identification and tracking, this approach entails considerable financial investment and logistical complexities. The application authoring process, responsible for the system's capacity to provide evacuation information and material handling guidance, successfully addresses a critical void in existing visualization tools tailored for construction sites.

Of particular significance is the fact that the proposed system, while requiring specialized computer programming expertise for its development and maintenance, obviates the need for resource-intensive solutions such as CCTV-based monitoring, thus offering a more streamlined and cost-effective alternative for enhancing safety within construction environments.

The proposed system underwent rigorous testing in laboratory and real-world construction environments to validate its performance and the accuracy of its algorithms. Leveraging Augmented Reality (AR) technology, the system successfully delivered real-time information to users, including virtual green line path visualization, voice and arrow-based directional guidance, exit identification, and dynamic distance calculations superimposed onto the physical scene via mobile devices. A comprehensive experiment conducted within the engine building construction project at Chulalongkorn University Demonstration Secondary School across three floors demonstrated the system's efficacy. Comparative analysis with the MATALL Laser distance meter revealed a consistently low percentage difference in distance measurements, underscoring the system's accuracy and reliability in generating real-time evacuation guidance. Providing crucial information such as current location, exit points, evacuation route distances, and multi-modal guidance facilitates rapid and informed decision-making, enabling users to navigate safely and efficiently during emergencies.

Despite the promising results, several limitations were identified as follows:

These limitations highlight areas for future research and development, aiming to refine and expand the capabilities of the proposed system and maximize its potential for enhancing safety across a broader range of construction and emergency response scenarios.