ISO 21501 is the recognised standard for optical particle counter calibration introduced by the International Organization for Standardisation (ISO) in 2007 with the purpose of providing ‘…a calibration procedure and verification method for particle counters, so as to minimise the inaccuracy in the measurement result by a counter, as well as the difference in the results measured by different instruments.’
The publication includes four sections, each dedicated to a specific particle counting technology/application:
- Light scattering aerosol spectrometer
- Light scattering liquid-borne particle counter
- Light extinction liquid-borne particle counter
- Light scattering airborne particle counter for clean spaces.
Part 4, which has the title: ‘Determination of particle size distribution – Single particle light interaction methods’, specifically refers to the Light scattering aerosol particle counter (LSAPC).