Aerosol Instrumentation and Calibration
To support measurement quality control and instrument development, the Aerosol Physics Laboratory has extensive capabilities for aerosol instrument characterization. The most important tool used in the characterization is the Singly Charged Aerosol Reference (SCAR), which is a number concentration reference built in our laboratory. Combining the traditional calibration methods and SCAR, it is possible to carry out traceable number concentration calibration in an exceptionally wide particle size range from few nanometers up to 5µm. Additionally, the SCAR serves also as a very versatile test aerosol generation tool for all instrument characterization applications.
For particle size reference, Differential Mobility Analyzers (DMA) are typically used. The particle generation system of the SCAR is capable of producing singly charge particles up to 5 um. Therefore, it is possible to extend the size reference use of the DMA. For this purpose we have a custom-made DMA designed for large particle sizes. The size range of this unique DMA is approximately from 300nm to 5µm. As a size reference for beyond that, a Vibrating Orifice Aerosol Generator (VOAG) can be used.
Low-level electrical current measurement is closely linked to our instrument development and characterization activities. We have expertise and both commercial and custom-made equipment for measuring femtoampere level current signals.