Criteria for the choice of a denuder sampling technique devoted to the measurement of atmospheric nirous and nitric acids

The criteria for the choice of the most appropriate denuder coating and set-up devoted to the measurement of atmospheric gaseous species are discussed and applied ton the problem of nitrous and nitric acid determination in real conditions. The various phenomena which may bias these determinations (instability of nitrate ion, collection of interferent compounds, oxidation of nitrate ion etc.) are exmined. A denuder method for a reliable measurement of nitrous and nitric acids in all en vironmental conditions is described and validated in the field. © 1990.