Aerosol Science: Technology and Applications

Chapter 3

Recommendations for Aerosol Sampling

Alfred Wiedensohler¹, Wolfram Birmili¹, Jean-Philippe Putaud², and John Ogren³

¹Leibniz Institute for Tropospheric Research, Germany

²European Commission, Joint Research Centre, Italy

³NOAA ESRL GMD, USA

3.1 Introduction

Atmospheric aerosols are measured in many parts of the globe in order to evaluate their various effects on climate, visibility, and human health. ‘Particulate matter’ (PM) can also be used to describe the atmospheric particulate phase. Atmospheric particles can occur at various diameters from 1 nm to 100 µm. Within this range, the atmospheric particle size distribution is usually considered a continuous function. The most important subdivisions concern fine particles (<1 µm) and coarse particles (>1 µm). Fine particles originate mainly from gas-to-particle conversion and combustion, while coarse particles are typically the result of abrasion or resuspension. The fine particle range can be further divided into the accumulation mode (0.1–1.0 µm), Aitken mode (20–100 nm), and nucleation mode (1–20 nm) ranges. A widely used convention is ‘ultrafine particles’ for the size range smaller than 100 nm. Particle mass concentrations are usually determined for certain aerodynamic size ranges (PM₁₀, PM_2.5, PM₁) that simulate different depths of particle penetration into the human airways. The chemical composition of aerosol particles can strongly depend on their origin and thus on their size. In the atmosphere, particles may exhibit ...