What are particle sizes presented in millimeters?
The size of contaminants and particles are usually described in microns, a metric unit of measure where one micron is one-millionth of a meter. There are 25,400 microns in one inch. The eye can see particles to about 40 microns.
The size of some contaminants and particles are indicated in the table below.
|
Particle
|
Particle Size
(microns) |
|
one inch
|
25,400
|
|
dot (.)
|
615
|
|
Eye of a Needle
|
1,230
|
|
Glass Wool
|
1000
|
|
Mist
|
70 - 350
|
|
Fertilizer
|
10 - 1000
|
|
Pollens
|
10 - 1000
|
|
Textile Fibers
|
10 - 1000
|
|
Fiberglass Insulation
|
1 - 1000
|
|
Human Hair
|
40 - 300
|
|
Human Hair
|
60 - 600
|
|
Hair
|
5 - 200
|
|
Cement Dust
|
3 - 100
|
|
Mold Spores
|
10 - 30
|
|
Starches
|
3 - 100
|
|
Red Blood Cells
|
5 - 10
|
|
Mold
|
3 - 12
|
|
Mustard
|
6 - 10
|
|
Antiperspirant
|
6 - 10
|
|
Textile Dust
|
6 - 20
|
|
Gelatin
|
5 - 90
|
|
Spores
|
3 - 40
|
|
Combustion-related Carbon Monoxide from motor vehicles, wood burning, open burning, industrial processes
|
up to 2.5
|
|
Fly Ash
|
1 - 1000
|
|
Coal Dust
|
1 - 100
|
|
Iron Dust
|
4 - 20
|
|
Smoke from Synthetic Materials
|
1 - 50
|
|
Lead Dust
|
2
|
|
Talcum Dust
|
0.5 - 50
|
|
Asbestos
|
0.7 - 90
|
|
Calcium Zink Dust
|
0.7 - 20
|
|
Paint Pigments
|
0.1 - 5
|
|
Metallurgical Dust
|
0.1 - 1000
|
|
Metallurgical Fumes
|
0.1 - 1000
|
|
Humidifier
|
0.9 - 3
|
|
Copier Toner
|
0.5 - 15
|
|
Liquid Droplets
|
0.5 - 5
|
|
Anthrax
|
1 - 5
|
|
Yeast Cells
|
1 - 50
|
|
Carbon Black Dust
|
0.2 - 10
|
|
Atmospheric Dust
|
0.001 - 40
|
|
Bacteria
|
0.3 - 60
|
|
Bromine
|
0.1 - 0.7
|
|
Lead
|
0.1 - 0.7
|
|
Radioactive Fallout
|
0.1 - 10
|
|
Rosin Smoke
|
0.01 - 1
|
|
Combustion
|
0.01 - 0.1
|
|
Smoke from Natural Materials
|
0.01 - 0.1
|
|
Oil Smoke
|
0.03 - 1
|
|
Tobacco Smoke
|
0.01 - 4
|
|
Viruses
|
0.005 - 0.3
|
|
Typical Atmospheric Dust
|
0.001 to 30
|
|
Pesticides & Herbicides
|
0.001
|
|
Carbon Dioxide
|
0.00065
|
|
Oxygen
|
0.0005
|
|
• one micron is one-millionth of a meter
|
|