Evaluation of wireless sensor technologies in a firefighting environment

In firefighter environments navigational support could help to reduce casualties. While exact indoor localization is still a research problem, an alternative may be a bread crumb based approach in which not the exact localization but the recovery of laid out wireless sensor nodes is crucial. Recovery, however, can be enabled using sensors typically employed for indoor positioning in wireless sensor networks (WSNs). Such sensors include infrared, ultrasound and radio. Only little information is available on the behavior of these sensors under the influence of a firefighter environment. In this paper first a report of the evaluation of these sensor technologies under the harsh conditions in a firefighting training facility is given. Secondly, tests considering received signal strength in respect to firefighter equipment, postures, movement patterns and antenna positions are presented. Third, two potential antenna configurations are evaluated. We show that the evaluated sensor technologies and antennas may be used to realize the envisioned navigation tool. We conclude that antenna placement is crucial and propose the front side of the helmet as optimal location for a directional antenna.