Validierung eines neuen Verfahrens zur Kalibrierung von Peroxiacetylnitrat (PAN)-Analysatoren

A novel method for the calibration of analytical instruments for the measurement of peroxy acetyl nitrate (PAN) was investigated. The commercially available calibration system employs the quantitative conversion of NO standard mixtures of known concentration in a photochemical flow reactor. The results obtained in this study showed that the NO to PAN conversion efficiency is 92±3% (1 σ) over a wide range of operational conditions. The sum of all identified products (PAN, CH 3 ONO 2 , NO 2 and NO) amounts to 98±5%. The precision of the PAN calibration unit is <±0.5%, after a burn in period of 1 h. Comparison of two different units using the same NO standard showed agreement within 1%. The comparison of 5 different units with different NO-calibration standards during the Berlin Ozone Experiment showed agreement within 10%. The new calibration unit provides an easy to use and accurate method for the calibration of PAN analyzers.