This paper presents an innovative wearable smart Personal Protective Equipment (PPE) designed to significantly enhance safety in various work environments, with a particular focus on minimizing the incidence of machine accidents prevalent in manufacturing and construction industries. The proposed system takes the form of working spectacles, integrating a battery-powered autonomous unit capable of continuously monitoring the presence of nearby machinery and alerting the operator to potential dangers. By detecting moving machines equipped with specific tag devices, the user is immediately warned upon entering a predefined dangerous zone. The foundational technology for precise indoor ranging, crucial for this system, is Ultra-Wideband (UWB), leveraging its time-of-flight capabilities to accurately determine distances. The system continuously monitors the distance to machine tags and triggers an immediate alarm—manifested as light or vibration—if this distance falls below a predetermined safety threshold. Furthermore, an innovative infrared receiver-transmitter pair is integrated into both the user's spectacles and the tag devices, enabling the system to detect if the user is actively pointing at the potential hazard, thereby ensuring explicit awareness of the danger. This paper details the prototypal performances of the menace-to-human ranging capabilities and the effectiveness of the infrared targeting system.