Atmospheric air -- Determination of the concentration of atmospheric aerosol particles

This document specifies a standard method for determining the particle number concentration in atmospheric air up to approximately 10⁷ cm⁻³, with an average time equal to or greater than 1 min. This standard method is based on a condensation particle counter (CPC) operated in counting mode, with appropriate dilution for concentrations above the counting range. Performance characteristics and minimum requirements for the instruments used are also defined. The lower and upper dimensions considered in this document are 10 nm and a few microns, respectively. This document provides guidance on sampling, measurement, data handling, and QA/QC procedures, including calibration parameters.