Particulate Matter (PM) refers to a mixture of solid particles and liquid droplets found in the air. These particles can include dust, dirt, soot, and smoke, and they vary in size. PM is often categorized by size, with PM10 and PM2.5 being the most common. PM10 includes particles with a diameter of 10 micrometers or less, while PM2.5 includes finer particles with a diameter of 2.5 micrometers or less.
