This paper presents an Augmented and Virtual Reality (AR/VR) based IoT prototype system. Performing maintenance tasks in a complex environment is quite challenging and difficult due to complex, and possibly, underground facilities, uneasy access, human factors, heavy machineries, etc. Current technology is not acceptable because of significant delays in communication and data transmission, missing multi-input interfaces, and simultaneous supervision of multiple workers who are working in the extreme environment. The aim is to technically advance and combine several technologies and integrate them as integral part of a personnel safety system to improve safety, maintain availability, reduce errors and decrease the time needed for scheduled or ad hoc interventions. We emphasize on the aspects that were made “feasible” on the worker's side due to the equipment used (mobile computing equipment). We present that the demanding tasks that previously were simply undertaken on the fixed infrastructure are now possible on the mobile end. The research challenges lie in the development of real-time data-transmission, instantaneous analysis of data coming from different inputs, local intelligence in low power embedded systems, interaction with multiple on-site users, complex user interfaces, portability and wearability. This work is part EDUSAFE, a Marie Curie ITN (Initial Training Network) project focusing on research into the use of Augmented and Virtual Reality (AR/VR) during planned and ad hoc maintenance in extreme work environments.