Size distribution of sulfur-containing compounds in urban aerosols

An aerosol spectrometer was used to determine the size distribution of sulfur-containing particulate materials in urban areas of northern and southern California. Based on a limited number of summer daytime samples, a typical Menlo Park size distribution had a mass median diameter of about 0.3 μ with upper and lower quartiles at about 0.9 and 0.1 μ, respectively. A typical Pasadena size distribution would be about one-tenth micron larger. The diameters given are for equivalent unit-density spheres of the same settling velocities as the sampled particles.