This paper presents an Internet of Things (IoT) approach for monitoring temperature and relative humidity applied to product maintenance in hospitals or pharmaceutical entities. Our goal is to integrate a low-cost and scalable network of smart sensors capable of mapping large areas in real-time. In this article, we provide a comprehensive insight into the technologies that compose the IoT architecture: (i) the node layer composed of Wireless Sensor Network (WSN), (ii) the local management layer of the WSN and (iii) the cloud-based layer for enabling remote monitoring. To the date, our IoT system has been working during (8) months in The Hospital Universitario San Ignacio, a 4th level university hospital located in Bogota, Colombia. Here, we present a field report of this work-in-progress system.