The deposition of aerosol in the human respiratory tract was calculated as a function of the particle size and particle density of the aerosol, the manner of breathing, and various parameters which control the degree of mixing of inspired air with the dead space air and with the lung air. The computations were performed on an electronic computer, which allowed a full analysis of the effects of the various parameters. Agreement between the computed total deposition curves, and published experimental data was very satisfactory. The computed curves exhibited the minimum in total deposition previously established experimentally, in the region of 0.3 μ. The maximum in the alveolar deposition curve was about 1 μ for particles of unit density, confirming the results of Brown, Cook, Ney, and Hatch for nose breathing. Its position was a function of the density of the aerosol particles, but was relatively insensitive to the tidal volume and other breathing parameters. The opposite held in regard to the value of the maximum, which was totally uninfluenced by the particle density, but was affected by the breathing parameters.

A study was made on the capture of monodispersed aerosol particles in the size range 0.8 ‐ 2.9 μm, in a screen‐supported fixed bed, and in a fixed and a fluidized bed supported on a grid of low superficial area (0.56%). All beds were composed of glass beads of mean size 425 μm. Relatively high capture efficiency was observed in the grid regions of both fixed and fluidized beds supported in this manner, with relatively lower capture efficiency observed in the vicinity of the screen. Aerosol capture efficiency per unit of bed volume in the body of the fixed beds was not significantly affected by the method of support, and was larger than was the case with the fluidized bed. An estimate of aerosol capture efficiency at the grid jets, based on an equivalent pneumatic transport line concept, was in reasonable agreement with experiment.

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The performance of a venturi scrubber with a 1‐in. by 3‐in. throat was determined using monodispersed uranine‐methylene blue aerosols in the size range 0.8 to 3.0μm at throat velocities ranging from 109.6 ft/sec to 245 ft/sec. Separate measurements on the water separator showed that substantial aerosol removal took place in this unit, and the efficiency of the scrubber itself was calculated from these measurements plus overall efficiency measurements on the combination scrubber and separator. These results were compared with values obtained from a theoretical model and agreement was generally satisfactory, although the theoretical efficiencies were lower than the experimental efficiencies at the highest air velocities, and viceversa. This discrepancy may be due to a number of factors which are discussed.

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