A Distributed Infrastructure for Real-time Continuous VOC Monitoring in Hazardous Sites

The real deployment is described of a distributed point source monitoring system based on wireless sensor networks in an industrial site where dangerous substances are produced, used and stored. The system consists of a Wireless Sensor Network using Photo-Ionisation Detectors, continuously monitoring the Volatile Organic Compound concentration in the petrochemical plant at unprecedented time/space scale. Internet connectivity is provided via TCP/IP over GPRS gateways at a one-minute sampling rate; thus, providing plant management and, possibly, environmental authorities with an unprecedented tool for immediate warning in case of critical events. The platform is organised into subnetworks, each including a gateway unit wirelessly connected to the WSN nodes, hence providing an easily deployable standalone infrastructure featuring a high degree of scalability and reconfigurability, with minimal intrusiveness or obtrusiveness. Environmental and process data are forwarded to a remote server and made available to the authenticated users through a rich user interface that provides data rendering in various formats and worldwide access to data. Experimental results show an excellent efficiency of the WSN system in terms of communication, making it a very flexible and cost-effective tool for environmental monitoring issues.