Question: what is the difference between a fine vs. course particulate pollutant?
Answer: Particles of concern can be grouped into two main categories: Coarse particles (also known as PM10-2.5): particles with diameters generally larger than 2.5 µm and smaller than, or equal to, 10 µm in diameter. ... Fine particles (also known as PM2.5): particles generally 2.5 µm in diameter or smaller.