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A Survey on Environmental Monitoring Systems using Wireless Sensor Networks

Air pollution is considered as crucial for people’s comfort, health, and safety. Monitoring the air pollution is crucial in both environments (indoors and outdoors), and can be accomplished using a small number of inexpensive sensing unities, distributed over an area of interest to measure the level of various critical gases including CO , H 2 S , and NO 2 . The deployment of Wireless Sensor Network offers an alternative solution through scattering a large number of disposable sensor nodes over an area of interest. Scientists may directly retrieve the sensed data from sensor field through a web server application. This paper provides a comprehensive review on the available solutions that support the wireless sensor network environmental monitoring. The existing systems are intensively studied and categorized into: indoor, outdoor, and greenhouse environmental monitoring systems