## 2 Literature Review
### Review of Global BIM Guides  
Table 2 shows the foreign BIM guides frequently referred to when major public and private organizations in the BIM-advanced countries have developed BIM guidelines for their projects. Most of these guides, just like the domestic ones above, have mainly dwelled on the BIM designers' perspective. However, the guide developed by Pennsylvania State University, USA, addresses the performance of the PO(s) at the BIM design procurement stage [20]. The National Institute of Building Sciences (NIBS), USA, also specifically prepared a BIM guide for the PO(s) [21], which outlines how they should develop requirements for the application of BIM, and explains how to include these requirements in contracts to plan, design, construct, and operate buildings. The NIBS guide also provides recommendations for processes, standards, and deliverables for BIM operation that could be shared by the PO and other project participants to meet specific BIM needs for individual project conditions. \begin{table}
\begin{tabular}{c p{227.6 pt}} \hline \hline
**Authors** & **Major Contents** \\ \hline
[12] & Investigates the previous BIM guides in Korea and abroad for developing open BIM guidelines in Korea \\
[13] & Identifies preliminary study on the level of information and standardization in the BIM design process in Finland and Denmark \\ \hline
[14] & Sets the direction of BIM quality criteria through analyzing the existing quality management approaches among domestic and foreign BIM guides \\ \hline
[15] & Identifies the role of BIM guidelines through case studies in foreign countries and deriving the direction of BIM guidelines’ development \\ \hline
[16] & Investigates BIM procurement instructions in foreign countries for the development of BIM guide criteria applicable to the overall areas in the construction industry \\ \hline
[17] & Analyzes BIM guidelines in Korea and foreign countries for the application of BIM to the project planning stage and deriving the elements to be included in BIM guidelines \\ \hline
[18] & Analyzes the items necessary for green BIM guidelines in conjunction with the Level of Development (LOD), and suggests the measurements in each LOD stage \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Previous studies on BIM guides and instructions. The Italian State Property Agency (that is, the Agenzia Del Demanio) developed a BIM guide to digitize the information on Italian real estate properties [30]. This agency is the public entity that manages the Italian state's real estate assets, and administers a portfolio of around 42,000 assets worth EUR 61 billion. From 2016, the agency has adopted the BIM methodology to create three-dimensional digital files of each property managed, in order to optimize property maintenance operations and verify service performance for the purpose of public savings through cutting down management costs. The BIM guide mainly includes the principles for systematically coding documents, the required contents and levels of data models, and the templates for enhancing the interoperability of diverse software, all of which are tailored to focus on business purposes. The International Organization for Standardization (ISO) developed ISO 19650 in 2018, based on the principles and context of a British BIM standard as the international framework for managing information over the life cycle of a facility [25]. This is a set of rules including four documents: ISO 19650-1 explains the principles and concepts; ISO