Evaluation of a Wireless Sensor Network with Low Cost and Low Energy Consumption for Fire Detection and Monitoring

Wireless sensor networks (WSNs) may offer the opportunity to eliminate most of the extension cables and wires in digital systems, allowing operation far from any infrastructure. This opportunity coincides with a great increase in cost-effectiveness in an overall fire detection and monitoring system for forests, buildings or industrial sites. Our purpose is to evaluate this opportunity. After presenting the three main technologies for wireless communications to non experts, we retained the Zigbee protocol for this study. We then investigated whether the use of a WSN with this protocol is valuable for measuring heat quantities during a fire spreading over a vegetation fuel bed. Experiments are performed under both lab scale indoor and real outdoor conditions. The method consists of comparing temperatures and radiant heat fluxes gained with the wireless technology with those recorded at the same location through a wired data acquisition system. Delays due to the wireless radio communications are identified and explained. We also observe information loss for measurements performed in the fire front. Finally, we highlight that fires can be detected satisfactorily by WSN equipment in indoor and outdoor conditions. However, we also show that measurement accuracy obtained from wired systems cannot be obtained with the present wireless technology, and we do not recommend their use at the present time for fire monitoring and mitigation.