Vergleich von Luftschadstoffen in unterschiedlichen Mittelungszeiträumen

National and international standards of ambient pollutants often refer to different measurement periods, which makes comparisons difficult. Therefore it is helpful to have factors which allow a conversion. Such factors are derived on the basis of the 0.5 h values of sulfur dioxide, nitrogen dioxide, total suspended particulates (3 h moving average), carbon monoxide and ozone measured in 1987 and 1988 at eight stations in Northrhine Westfalia. Assuming a lognormal distribution, the parameters of these data and the conversion factors are determined. These allow a conversion of averaging periods from 0.5 h to 24 h. Furthermore, conversion from 0.5 h maxima to 98 or 95 percentiles in possible. The application of these factors should be restricted to situations with comparable air quality.