I have recently created pm2.5 and have it on 3 questions so far.
update: 8 questions now.
I have also written the following tag Wiki excerpt:
PM2.5 is one size classification of airborne particulate matter, but has become a popular catch phrase for any small-sized particulate matter relevant both to atmospheric heating/cooling (as a greenhouse "gas") due to their high thermal emissivity and sunlight absorption, and as a pollutant with health consequences. Other particle sizes can use this tag as well, including PM10, PM1, PM0.1
How do people feel about this? Okay, not okay? better wording?