University of York's 2B Technologies Single Channel Ozone Monitor is a UV photometric gas analyser (254nm) which has the capability to measure the amount of ozone in the air from 3 ppb concentrations up to 250 ppm. The instrument precision is 1.5 ppbV or 2% of the reading. The instrument has a fast response time of 10 seconds (0.1 Hz). The gas concentration is displayed in real time and is logged via a standard RS-232 interface and data can also be logged internally. The instrument is small, lightweight and low power making it ideal for aircraft and balloon measurements where high spatial resolution is desired. The 10 second data can be averaged to produce 1 minute, 5 minute and 1 hr data automatically.