## 5 Discussion
### FM Core Competence: Human Factor  
This core competence focuses on protecting the environment and the people who use the facility, minimising risks and liabilities and positively impacting all stakeholders. All the articles belonging to this competence concern indoor environmental monitoring. Four out of seven articles [48; 51; 52; 53] are on air quality monitoring. Two articles, [49] and [50], are about thermal comfort. [PERSON] et al. (2020) [54] discuss environmental monitoring and emotion detection to provide insights into spaces' comfort level. Almost all articles focus their attention on the BIM-Wireless Sensors Network (WSN) connection, aiming to visualise real-time sensors data on the BIM model. The only exception is the research conducted by [PERSON] et al. (2018) [51], where the BIM model is used to extract building information stored in a tabular format and converted into ontology instances.  
Table 9 shows the type of monitored data in each article.  
The integration between BIM and WSN offers great advantages to the monitoring systems developed in the various research studies. Through this integration, it is possible to better visualise a multitude of data relating to environmental monitoring and associated with multiple elements and spaces. Following this integration and creating the database containing all environmental data (e.g., temperature, humidity, light, noise, etc.), it is possible not only to monitor thermal/air quality problems to ensure comfort for users but also to detect the need for maintenance of building components.  
However, during these processes, interoperability between different information systems and information sharing between various stakeholders remains challenging. Management of these heterogeneous data should be further investigated. Moreover, battery capacity and operation duration could be a significant limitation of a WSN. Therefore, it is necessary to consider adopting high-capacity batteries or a fixed power source for long-term operation.  
To conclude, protecting the environment in which people live/work is certainly among the priorities that FM will have to face in the near future. Although the use of new technologies and sensors is widespread and certainly not new, the main challenge for this (but also other) core competencies is data/information interoperability. Finally, a novelty  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Reference** & **Scope** & **Issue** & **Sensors** \\ \hline [PERSON] et al. (2014) & Indoor Environmental & Air quality & Temperature \\  & monitoring & & Particulate Matter \\ \hline [PERSON] et al. (2018) & Indoor Environmental & & Temperature \\  & monitoring & & Humidity \\  & monitoring & Air quality & Noise \\  & monitoring & & Light \\  & & Gas (CO, CO\({}_{2}\), Radon, Methane) \\ \hline [PERSON] et al. (2019) & Indoor Environmental & & Temperature \\  & monitoring & Air quality & Humidity \\  & & Wind speed around person \\ \hline [PERSON] et al. (2020) & Indoor Environmental & & Carbon Monoxide \\  & monitoring & Air quality & Temperature \\  & & Humidity \\ \hline [PERSON] et al. (2014) & Indoor Environmental & & Temperature \\  & monitoring & Thermal comfort & Humidity \\ \hline [PERSON] et al. (2017) & Indoor Environmental & & Temperature \\  & monitoring & Thermal comfort & Thermographic camera \\ \hline [PERSON] et al. (2020) & Indoor Environmental & Air quality & Temperature \\  & monitoring & Thermal comfort & Noise \\  & & Light \\  & & CO, CO\({}_{2}\), TVOC \\ \hline \hline \end{tabular}
\end{table}
Table 9: Human factor core competence: type of sensors used in studies on BIM–Wireless Sensors Network (WSN) integration for indoor environmental monitoring.  
that emerged in this review is the improvement of the comfort level in facilities spaces through users emotion detection. In this direction, more effort should be focused to better fit building spaces to users.