## 1 Introduction  
### Background and Purpose of the Study  
Fabrication facility (FAB) is a manufacturing facility composed of numerous sophisticated equipment [1]. Parallel to the advancement of manufacturing technology, the FAB industry sector, represented by the manufacture of semiconductors and display panels, is undergoing a change by overhauling the conventional production method of simply delivering new products. Instead, it started to employ a new way to produce new products by predicting the market demand in advance, or to design new production lines that can help match with the tailor-made products requested by the client in a short span of time. In view of such characteristics of the industry that the timely production of the required products is of high priority, the FAB is usually constructed by implementing fast-track construction thus that the proposed production schedule can be met [2]. As defined by [PERSON] et al. [3], Building Information Modeling (BIM) entails the process of creating, sharing, exchanging, and managing project information as a single repository of data throughout the whole building lifecycle effectively and efficiently. This single repository database function of BIM enables not only easy access and sharing of information by all project stakeholders [4] but also allows immediate analysis of the benefits of various cost-time options since the time and cost dimensions can be added to the model [5]. Considering these benefits, the active implementation of BIM in FAB construction projects was initiated by project owners reflecting his/her needs for fast-track construction to ensure meeting the time schedule of production lines operation as well as for securing a 3D model of high consistency, which can ensure the efficient operation and maintenance after the construction completion. However, BIM implementation in domestic FAB construction projects is in such an early stage that they are benchmarking the BIM implementation method applied in the conventional building sector. It is noteworthy that the project owners are recruiting personnel with BIM experience from outside in order to adopt and implement BIM in FAB construction projects. As such, in order to enhance the usability of BIM in FAB construction projects, it is necessary for the workforce recruited from outside to have a correct understanding of FAB construction and to be able to command BIM properly in accordance with the characteristics of FAB. In addition, the existing participants of FAB construction projects need to acquire and possess new competencies, which are required for commanding BIM properly in FAB construction projects. Whether for the recruited workforce from outside or for the existing FAB construction participants, having a clear understanding of required BIM competencies for FAB projects and equipping them with such accordingly will only guarantee the benefits of BIM implementation. Accordingly, this study aims to assess and present BIM competencies needed for the successful implementation of BIM in FAB construction projects and for enhancing the usability thereof. In addition, this study will identify the current BIM competency status as well as the correlation between career characteristics and BIM competencies of project participants engaged in FAB construction projects where BIM was implemented. Although there are previous studies on identifying BIM competencies, such as [PERSON] et al. [6], which identified 43 competency elements further subcategorized into essential, common, and job-specific competencies for the eight BIM job types (e.g., BIM project manager, director, BIM manager, etc. ), this study furthers the body of knowledge on BIM competencies by specifically identifying the needed BIM competencies for FAB construction projects. As such, it can be expected that the findings of this study be used as a base for the development of customized BIM educational programs, thus as to enhance the competencies of project participants of BIM-based FAB construction projects in the future.