Short description
This standard describes the use of optical aerosol spectrometers to determine the particle number size distribution and the number concentration in ambient air and in test aerosols. The detectable particle size range extends from about 0,07 µm to about 25 µm. Number concentrations of less than 1 cm-3 up to a maximum of about 100000 cm-3 can be measured. The temporal resolution is in the range of less than one second to several minutes. This standard defines a set of instrument parameters as well as the procedures for their determination, but does not specify minimum requirements.