An assessment of the luminol chemiluminescence technique for measurement of NO2 in ambient air

The detection of NO₂ by its chemiluminescent reaction with luminol is a rapid and sensitive means of measuring atmospheric NO₂. However, testing and field use of a commercial NO₂ monitor employing this detection scheme have shown that several corrections are necessary in order to obtain accurate NO₂ data at low concentrations. In use aboard aircraft, the NO₂ data must be corrected for zero offset, altitude (i.e. pressure), nonlinearity of response, and interferences from ozone and PAN. Detector response is dependent on the age of luminol reagent solution. This paper describes the tests performed to determine correction factors, the algorithms and order of precedence for applying the corrections, and other observations regarding detector performance.