BS ISO 21501-1:2025 - Page 2

This document specifies characteristics of a light scattering aerosol spectrometer (LSAS) which is used for measuring the size, number concentration and number-based size distribution of particles suspended in a gas. This document provide the calibration procedure and the validation method for aerosol spectrometers.

This document applies to:

• characterization of metered dose inhalers (MDI), dry powder inhalers (DPI) and nebulizers in pharmacy;

• production control of active agents;

• cut-off determination: impactors, cyclones and impingers;

• atmospheric aerosols: bio-aerosols, stables or composting facilities, nebulized droplets, measurements in street tunnels;

• fractional separation efficiency determination of filters.