"PM2.5" is a standard term[1,2], along with "PM10". [1] https://www3.epa.gov/ttn/amtic/amticpm.html https://www3.epa.gov/ttn/amtic/amticpm.html [2] https://cf

"PM2.5" is a standard term[1,2], along with "PM10". [1] https://www3.epa.gov/ttn/amtic/amticpm.html https://www3.epa.gov/ttn/amtic/amticpm.html [2] https://cfpub.epa.gov/airnow/index.cfm?action=aqibasics.particle https://cfpub.epa.gov/airnow/index.cfm?action=aqibasics.part...