PM2.5 definitions

PM2.5

Particles in air of with a maximum aerodynamic diameter of 2.5 µm
Found on https://sis.nlm.nih.gov/enviro/iupacglossary/annex1.html

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PM2.5

Particulate matter with a mean aerodynamic diameter of 2.5 micrometers (0.0001 in.) or less.
Found on https://www.encyclo.co.uk/local/22831

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