In-situ calibration of pollutant measuring-units by means of remotely-controlled traveling standards

The increasing diffusion of pollutant measuring units which are installed over wide areas along with the short calibration interval of several sensors for pollutant quantities requires new calibration infrastructures to be developed. This paper describes an attempt to develop an innovative calibration system which is based on traveling standards and which does not require a unit to be removed from the measuring site during the calibration process. The calibration system is based on a simple traveling standard, which is composed of one or more gas cylinders with known standard gas mixtures, a cell with standard sensors and a network-enabled contro-unit, which allows the entire standard to be remotely exercised. A prototype of the proposed system is described and the initial results obtained in the case of sensors reported.