Lets start with some fundamentals before everyone jumps the gun, I have a little info I will share with ya all..... About Micron Sizes and Particle Filtration
Filtration is the process of forcing a liquid or gas through a porous medium to remove solid particles. The particles are measured or classified in microns. One micron equals 0.0000394". Absolute-rated filter cartridges will retain at least 99% of particles of a particular micron size.
Mesh
Micron Openings Micron
Size Inch per Inch Comparison
1 0.0000394" 12,000 Bacteria
10 0.000394" 1,250 Talcum Powder
20 0.00079" 625 Coal Dust (20 to 90 microns)
44 0.0017" 325 Lower Limit of Visibility
74 0.0029" 200 Human Hair
105 0.0041" 140 Table Salt
210 0.0083" 70 Beach Sand
Hope this helps
Kyle