# Empowering Clinical Engineering and Evidence-Based Maintenance with IoT and Indoor Navigation +
## 2 Related Works  
The manufacturer's maintenance recommendations have been subjected to a critical analysis process in recent years, which has prompted clinical engineers and health technology management (HTM) specialists to adopt evidence-based procedures to preserve the dependability and safety of medical equipment while using their resources wisely. Most hospital maintenance reports just outline the failures, repair procedures, and spare components used. These reports never mention any procedures that may have been taken to prevent the failure. The EBM-based approach allows a knowledge of the history of a failure and enables the monitoring and improvement of the current maintenance strategy so that the most appropriate approach can be found [17].  
A real-time locating system (RTLS) is used to automatically identify and track the locations of objects or people in real time. An RTLS is made up of specialized fixed receivers or readers that receive wireless signals from small badges or tags attached to items of interest and/or people to establish their location within a building or another confined indoor or outdoor space [18]. Tracking the position of portable MDs automatically improves a hospital's ability to manage medical equipment and respond to emergencies. The key benefit of adopting tracking technologies is that they show promise for enhancing operational efficiency by knowing the precise location of MDs [19; 20]. However, some drawbacks prevent such solutions from being deployed on a large scale in hospitals [21]. Current RTLS solutions prove inadequate in meeting the logistical support requirements of CE, as they are primarily designed for tracking patients and visitors [22]. Particularly, the usage of RTLS for asset/device tracking presents limitations concerning cost-effectiveness and scalability to large-scale manufacturing [23].  
There are currently no industry-standard solutions that enable positioning in every kind of indoor environment [24]. The literature presents several solutions based on different fingerprinting and multimodal approaches, using technologies such as RFID (radio frequency identification), UWB (ultra wide-band), infrared, ZigBee, WiFi, and Bluetooth Low Energy (BLE) [25]. BLE is a wireless personal area network (WPAN) technology created and managed by the Bluetooth special interest group. The synergy between good performance, low power consumption, and ubiquitous diffusion (BLE is available in all laptops, tablets, and smartphones) makes BLE an excellent candidate for a great variety of applications, including e-health applications, automotive applications, voice communications, and domotics for healthcare environments and smart houses [26]. Although RFID is flexible regarding tag size, the cost of RFID readers and unstable received signal strength make it less effective compared to BLE [27]. Moreover, RFID shows the drawback of requiring several RFID readers, while a WiFi-based approach offers a higher range but suffers from a lack of accuracy. Compared to traditional Bluetooth, BLE is designed to consume significantly less power while retaining a comparable communication range and accuracy (2-3 m) [28].