SIZE DISTRIBUTIONS OF TEST AEROSOLS FROM A LASKIN NOZZLE.

The authors conducted an experiment in which aerosol size distributions were measured with a differential-mobility particle sizer (DMPS). The DMPS consists of two instruments that together measure the size distribution of submicron aerosols according to the particles' electrical mobility. Experimental results show that the measured size distributions were at the upper limit of the instrument, which means that the true population mean diameter is probably somewhat larger than reported. This is particularly evident with the polyethylene glycol (PEG) material. The bimodal characteristic of the distribution is probably somewhat larger than reported. This is particularly evident with the polyethylene glycol (PEG) material. The bimodal characteristic of the distribution is probably a data-reduction error caused by multiple charging interferences from particles larger than 0. 8 mu m. The DMPS is less than ideal when significant numbers of large particles are present.