Continuous recording measuring devices are used for the detection of the outside air concentration of hydrocarbons SO2, NO2, NO, CO and oxydants. The Federal Government of West Germany has issued a law regarding preventive measures for maintaining clean air. The density of the concentration of different toxic airpolluting substances is supposed to be continuously recorded. Simultaneously, the meteorologically limiting quantities are supposed to be available, which are necessary for the description of the quality air situation. Like the new United States regulations, the goal is to obtain information about necessary remedial and preventive measures besides determining the degree of pollution.