Methods for gas-phase measurements of ozone, ozone precursors and aerosol precursors

The techniques currently available to measure the ambient atmospheric concentrations of O3, O3-precursors (including the odd-hydrogen free radicals), the oxidation products of these compounds, and gas-phase aerosol precursors are outlined below. This critical review focuses on the recent developments, and, in particular those developments that have been reported in the published literature since 1990. In general, the techniques are described in terms of the results of formal and informal comparisons of the techniques in measuring the compounds of interest in the ambient atmosphere. The article concludes with a brief discussion of calibration methods and standards and tests that should be routinely performed when measurements in ambient atmosphere are undertaken.