How big is a Micron?
A micrometer, commonly known as micron is one millionth of a meter, one
thousandth of a millimeter or one thousand nanometers. A strand of
human hair is about 100 microns wide and a red blood cell is approx. 8
microns in diameter.
The illustration below is 2,000 times larger than actual size.
Human Hair
.0035 inch
.0001 inch
.00254 mm
Micron
.001 inch
.0254 mm
.000039 inch
.001 mm
Micron Sizes
The chart below shows the sizes of common particles found in indoor air
and shows which air filter MERV ratings are effective against which types of
particles.