We have designed a new Technical Bulleting surrounding the size of particles in microns.
A similar chart has been available as a technical bulletin for many years. We has revamped this in April 2020 amidst the corona virus pandemic as part of the Airclean information suite for the understanding of Corona Virus
The following chart is a generalised summary of particle sizes that are encountered in both indoor and outdoor environments in microns. This chart can be used as guidance in the selection of air filters.