The Aitken counter: Revisiting its design and performance characteristics

Abstract

Advances in aerosol science have often been driven by innovations in aerosol instrumentation. Our ability to make real-time, multi-dimensional measurements of particle properties can be attributed to the development of a few important techniques throughout the history of aerosol science. One measurement technology that can be considered the father of aerosol instruments is the portable Aitken counter (PAC). The development of the PAC resulted in the first extensive field measurements of concentrations of particles smaller than those detectable using light microscopes. Prior publications have looked at the historical development of techniques related to measurement of one aerosol property. Here, we extend those previous historical studies by revisiting the design of the PAC and establishing its performance relative to existing instruments. This study provides a reference to educators who start their instrumentation course with a historical note about Aitken Particle Counters or researchers interested in quantifying changes in air quality over the time periods consistent with climate change studies.