Viruses: .3 microns (Covid-2, Corona, Flu)

Bacillus and Bacteria: .6 microns (Common Cold, e-Coli on the kitchen counter)

Dust: 2.5 microns (Fine Dust, Bed Bugs Excrements in mattresses)

Respiratory Droplets : 5-10 microns (All Waterbourne Particles, such as Cooking Smells or Smoke)

Pollen: 15 microns (angiosperms, produced by the anthers of the stamens in flowers)

Hair and Pet Dander

The Greentech HEPA Odogard Air Purifierfor instance is certified to remove 99.97% of all microscopic particles as small as 0.3 microns in size. 0.3 microns is the smallest possible particle size that can enter the lungs. Because of the added  ionisation technology, water molecules with the patricles attached to them attract each other, become heavier,  fall to the ground and hamper breathing it in.

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