Abstract |
A piezoelectric aerosol particle mass concentration monitor has been constructed and tested. This instrument detects, with high time resolution, the actual mass concentration of an aerosol cloud. The instrument uses an electrostatic precipitator to deposit aerosol particles directly onto a piezoelectric quartz crystal microbalance. The piezoelectric microbalance system consists of a quartz crystal detector, a reference crystal, two oscillator circuits, a frequency mixing circuit, and readout equipment. The electrostatic precipitator has an advantage over impaction collection devices because it collects the total mass of most aerosols on the crystal surface. It is not subject to a lower particle size cut-off within the range of most natural aerosols. A digital readout automatically indicates actual mass concentration in units of micrograms per cubic meter. Applications of the instrument include automobile particulate emissions monitoring, industrial hygiene measurements, ambient outdoor particulate mass concentration monitoring, industrial process control and source monitoring. The complete instrument is compact, allowing hand-carrying for fast, on-site measurement of particle mass loadings. (Author) |