The document discusses the selection of components for a wireless sensor network to monitor air pollution in an urban environment. It outlines criteria for selecting sensor network nodes, including 8 groups of criteria related to sensors, communication, energy, environmental resistance, technical aspects, expansion options, physical parameters, and price. 25 total criteria are identified and weighted based on their importance. The document then provides an example wireless sensor network implementation in Olomouc, Czech Republic, establishing requirements for monitoring various air pollutants using 15 sensor nodes. Finally, potential sensor node options are analyzed according to the outlined criteria.