PM

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THE ROLE OF PARTICULATE MATTER Air pollution comes in various forms. 

Particulate matter (PM) is just one. 

It describes the tiny bits of solid or liquid matter floating in the air – dust, smoke, droplets that are so small you usually can’t see them. 

PM is measured in sizes from ultra-fine (PM0.1), through to fine and all the way up to coarse (PM10). 

PM2.5 is very fine – less than a 30th of the width of a human hair.