### Virtual Reality and Immersive Technologies
From a technological viewpoint, immersion means that the system is capable of delivering an inclusive and extensive surrounding and vivid illusion of reality. Therefore, aspects such as display resolution, stereo capability, large field of view, tracking devices and input devices contribute to this illusion [21; 25]. From a psychological viewpoint, immersion is a mental and emotional state in which the user feels an isolation of the senses from the real world [22]. Therefore, immersive virtualisation technology allows the user to have the illusion of being physically, mentally and emotionally present in a virtual 3D environment [11; 13]. The VR field is complemented by game-based approaches to enhance learning and training methodologies, because games are focused on entertainment and engagement [26]. Video games have demonstrated a huge potential not only for entertainment, but also to generate abilities, skills and knowledge in vocational training by exploiting the main implicit characteristics that video games already have, i.e., engagement, entertainment and influencing attitudes and behaviours, that could allow us to extend and develop physical and mental capabilities, as mentioned in the work of [27]. Using these characteristics properly could allow users to spread out the training process, as well as achieving better user concentration and involvement. This is the basis of serious games. As mentioned in the work of [15], _\"a serious game is a digital game created with the intention to entertain and to achieve at least one additional goal (e.g., learning or health)\"_. Serious games are complete games (or simulations) that have an educational or learning background (e.g., training). Usually, they have a mission to fulfil; therefore, this requires users to think rationally, strategies, solve problems and test different decisions during the game to obtain the best results. Serious games applications have been actively used in several areas for learning purposes, as described by [26; 28], ranging from educational games for younger audiences to collaborative training and simulation environments for the industry. Some of the application fields include engineering education [29; 30], health [31; 32], operational skills training [28; 33; 34] and industrial plant operations [35; 36]. However, as mentioned by [14], the mere presence of VR, immersion and educational content in a game does not guarantee its effectiveness. In fact, the educational power of any serious game also depends on various additional factors. More specifically, the educational content must be sound, age-appropriate, well integrated into the game and presented clearly and the interface must be easy to use by the target audience, increasing interactivity with the VR environment. For this reason, an appropriate methodology must be used to design a game engaging user immersion and interactivity, to speed up the process for effective learning in vocational training. Additionally, this methodology should include the generation of a realistic scenario, that is, a suitable mission according to target audience and application domain; good usability and interaction; and, finally, a tool to measure outcomes and user experience [26]. In terms of realistic scenarios, interactivity and clear presentation of educational content, the use of three-dimensional models of high precision has allowed the building information modelling (BIM) methodology to be incorporated, which involves the generation and management of data of a building or infrastructure, using dynamic software and collaborative work with a single source of the project information, as presented in Section 1.2.