The size and concentration of droplets generated by coughing in human subjects:
https://pubmed.ncbi.nlm.nih.gov/18158720/
Results indicated the total average size distribution of the droplet nuclei was 0.58-5.42 microm, and 82% of droplet nuclei centered in 0.74-2.12 microm. The entire average size distribution of the coughed droplets was 0.62-15.9 microm, and the average mode size was 8.35 microm.
Data of microns below from: https://renownhealthproducts.com/rhp/library/facemasks_particle_size_and_your_chances_of_catching_covid-19/2020-04-07-240.html
Smoke from natural materials 0.01 to 0.1 micron
Cornstarch dust 0.1 to 0.8
Tobacco smoke 0.02 to 25 microns
Talcum dust 0.05 to 50 microns
Burning wood 0.2 to 3 microns
Outdoor dust 0.5 microns
Fog 1 to 40 microns
COVID-19 DROPLETS IN SNEEZES 5- 10 MICRONS
Pollen 10 to 1000 microns
Human hair is 60-120 micron