An accurate, continuously adjustable dilution system (1:10 to 1:104) for submicron aerosols

A new type of dilution system designed for submicron aerosols with high and medium particle concentrations is presented. The corresponding device was built on a small and portable scale. Dilution ratios can be selected continuously in the range between 1:10 and 1:104. Calibration measurements showed a linear relation between the dilution ratio and the control parameters within ± 2%. The dilution ratio was found to be independent of particle diameter in the size range between 0.01 and 0.7 μm. The dilution system was tested by sampling and measurement of aerosol particles from the stacks of different emission sources.