Measurements of the Particle Size Distribution of the Atmospheric Aerosol: II. Experimental Results and Discussion

Abstract Distribution data obtained by sampling the Baltimore aerosol with a cascade impactor are reported for the range between 0.4 and 20 microns radius. Data for the range between 70 A and 0.1 microns in radius were obtained in two runs with the rotating disk sampler. Greater variations were observed in the lower end of the spectrum than in the upper end. The theory of self-preserving size distributions was used with some success to correlate data obtained in this and other studies. When the theory applies and the r−4 subrange exists, the size distribution is given by n(r)=0.04ϕr−4 where ϕ is the volume fraction of aerosol material.