A Comprehensive User Experience and Usability Analysis of Foreign Construction Worker Equalization System through Integrated The Five Planes and Heuristic Evaluation

The digitalization of foreign construction worker equalization services at the Construction Services Development Board faces critical usability constraints that disrupt transnational bureaucratic efficiency. This study aims to optimize the user experience (UX) and usability of the web-based TKKA application by proposing a sequential integration of The Five Planes framework and Heuristic Evaluation. Data collection was conducted through user interviews and questionnaires to extract system requirements. The analysis synthesized 32 core UX specifications, which were subsequently mapped into the five architectural planes to guide the prototype redevelopment. Usability verification of the redeveloped system was executed through an expert-led Heuristic Evaluation combined with a user validation survey. The empirical results demonstrated a significant enhancement in usability, achieving a high Variable Index of 4.04 and an 80% user satisfaction rate (Cronbach’s Alpha = 0.981). This study confirms that integrating a structural design framework with expert heuristic screening effectively mitigates interface flaws, fulfills complex regulatory requirements, and accelerates digital public service workflows.