Chapter 6 Aerosol sampling and measurement techniques

Abstract

This chapter focuses on aerosol sampling and measurement techniques. The methods applied for atmospheric aerosol sampling include filters and cascade impactors, which collect the aerosol particles onto a surface. The collected sample must therefore, be evaluated for size and composition. Because accumulation mode aerosols (fine aerosol particles) contain a substantial fraction of liquid material at normal temperatures and humidities, these fine aerosol particles must be sized in situ without precipitation. Many aerosol-measuring techniques, such as the condensation nuclei counter, CNC, and filter collectors, integrate some response function of the instrument with the particle size distribution. In the particle-counting method, the response is essentially equal to the integral of the number distribution weighting. Simplicity during sampling may mandate the use of a particular collection method despite its other problems. The rapid development of modern electronics and inexpensive acquisition systems has led to in situ , automatic, and complex monitoring techniques. Collection methods are being replaced with both physical and chemical analysis in situ , automatic methods and digital electronic devices.