What Are The Particle Sizes Of Contaminants Found In Drinking Water?
The size of contaminants and particles are usually described in microns, a metric unit of measure where
- one micron is one-millionth of a metre
- 1 micron = 10-6Â m
In imperial units
- 1 inch = 25400 microns
- 1 micron = 1 / 25400 inch
In general, the eye can see particles larger than 40 microns.
Typical size of contaminants and particles:
| Particle | Particle Size (microns) |
|---|---|
| Anthrax | 1 - 5 |
| Antiperspirant | 6 - 10 |
| Asbestos | 0.7 - 90 |
| Atmospheric Dust | 0.001 - 40 |
| Auto and Car Emission | 1 - 150 |
| Bacteria | 0.3 - 60 |
| Beach Sand | 100 - 10000 |
| Bone Dust | 3 - 300 |
| Bromine | 0.1 - 0.7 |
| Burning Wood | 0.2 - 3 |
| Calcium Zinc Dust | 0.7 - 20 |
| Carbon Black Dust | 0.2 - 10 |
| Carbon Dioxide | 0.00065 |
| Cayenne Pepper | 15 - 1000 |
| Cement Dust | 3 - 100 |
| Clay, coarse | 2 - 4 |
| Clay, medium | 1 - 2 |
| Clay, fine | 0.5 - 1 |
| Coal Dust | 1 - 100 |
| Coal Flue Gas | 0.08 - 0.2 |
| Coffee | 5 - 400 |
| Combustion | 0.01 - 0.1 |
| Combustion-related - motor vehicles, wood burning, open burning, industrial processes |
up to 2.5 |
| Copier Toner | 0.5 - 15 |
| Corn Starch | 0.1 - 0.8 |
| Dot (.) | 615 |
| Dust Mites | 100 - 300 |
| Eye of a Needle | 1230 |
| Face Powder | 0.1 - 30 |
| Fertilizer | 10 - 1000 |
| Fiberglass Insulation | 1 - 1000 |
| Fly Ash | 1 - 1000 |
| Gelatin | 5 - 90 |
| Ginger | 25 - 40 |
| Glass Wool | 1000 |
| Grain Dusts | 5 - 1000 |
| Gravel, very fine (0.08 inch) | 2000 |
| Gravel, fine (0.16 inch) | 4000 |
| Gravel, medium (0.3 inch) | 8000 |
| Gravel, coarse (0.6 - 1.3 inches) | 15000 - 30000 |
| Gravel, very coarse (1.3 - 2.5 inches) | 30000 - 65000 |
| Ground Limestone | 10 - 1000 |
| Hair | 5 - 200 |
| Household dust | 0.05 - 100 |
| Human Hair | 40 - 300 |
| Human Sneeze | 10 - 100 |
| Humidifier | 0.9 - 3 |
| Insecticide Dusts | 0.5 - 10 |
| Iron Dust | 4 - 20 |
| Lead, solder radiator manufacturing - mean value | 1.3 |
| Lead, battery and lead powder manufacturing | 12 - 22 |
| Lead Dust | 0.1 - 0.7 |
| Liquid Droplets | 0.5 - 5 |
| Metallurgical Dust | 0.1 - 1000 |
| Metallurgical Fumes | 0.1 - 1000 |
| Milled Flour, Milled Corn | 1 - 100 |
| Mist | 70 - 350 |
| Mold | 3 - 12 |
| Mold Spores | 10 - 30 |
| Mustard | 6 - 10 |
| Oil Smoke | 0.03 - 1 |
| One inch | 25400 |
| Oxygen | 0.0005 |
| Paint Pigments | 0.1 - 5 |
| Pesticides & Herbicides | 0.001 |
| Pet Dander | 0.5 - 100 |
| Pollen | 10 - 1000 |
| Radioactive Fallout | 0.1 - 10 |
| Red Blood Cells | 5 - 10 |
| Rosin Smoke | 0.01 - 1 |
| Sand, very fine (0.0025 inch) | 62 |
| Sand, fine (0.005 inch) | 125 |
| Sand, medium (0.01 inch) | 250 |
| Sand, coarse (0.02 inch) | 500 |
| Sand, very coarse (0.02 inch) | 500 |
| Saw Dust | 30 - 600 |
| Sea Salt | 0.035 - 0.5 |
| Silt, coarse (0.0015) | 37 |
| Silt, medium (0.0006 - 0.0012 inche) | 16 - 30 |
| Silt, fine | Â 8 - 13 |
| Silt, very fine | 4 - 8 |
| Skin flakes | 0.5 - 10 |
| Smoke from Natural Materials | 0.01 - 0.1 |
| Smoke from Synthetic Materials | 1 - 50 |
| Smoldering or Flaming Cooking Oil | 0.03 - 0.9 |
| Spanish Moss Pollen | 150 - 750 |
| Spider web | 2 - 3 |
| Spores from plants | 3 - 100 |
| Starches | 3 - 100 |
| Sugars | 0.0008 - 0.005 |
| Talcum Dust | 0.5 - 50 |
| Tea Dust | 8 - 300 |
| Textile Dust | 6 - 20 |
| Textile Fibers | 10 - 1000 |
| Tobacco Smoke | 0.01 - 4 |
| Typical Atmospheric Dust | 0.001 to 30 |
| Viruses | 0.005 - 0.3 |
| Yeast Cells | 1 - 50 |
- one micron is one-millionth of a metre
- 1 micron = 10-6Â m
- 1 micron = 1000 nano metre
Airborne particles
Airborne particles are solids suspended in the air.
Larger particles - larger then 100 μm
- terminal velocities >Â 0.5 m/s
- fall out quickly
- includes hail, snow, insect debris, room dust, soot aggregates, coarse sand, gravel, and sea spray
Medium-size particles - in the range 1 to 100 μm
- sedimentation velocities greater than 0.2 m/s
- settles out slowly
- includes fine ice crystals, pollen, hair, large bacteria, windblown dust, fly ash, coal dust, silt, fine sand, and small dust
Small particles - less than 1 μm
- falls slowly, take days to years to settle out of a quiet atmosphere. In a turbulent atmosphere they may never settle out
- can be washed out by water or rain
- includes viruses, small bacteria, metallurgical fumes, soot, oil smoke, tobacco smoke, clay, and fumes
Hazardous Dust Particles
Smaller dust particles can be hazardous for humans. In many jurisdictions dust fractions at specified particle sizes in working environments are required to be measured.
Inhalable Dust
Airborne particles which can enter the nose and mouth during normal breathing. Particles of 100 microns diameter or less.
Thoracic Dust
Particles that will pass through the nose and throat, reaching the lungs. Particles of 10 microns diameter and less. Referred to as PM10 in the USA.
Respirable Dust
Particles that will penetrate into the gas exchange region of the lungs. A hazardous particulate size less than 5 microns. Particle sizes of 2.5 micron (PM2.5) are often used in USA.
The total allowable particle concentration - building materials, combustion products, mineral fibers and synthetic fibers (particles less than 10 μm) - specified by EPA (U.S. Environmental Protection Agency)
- 50 μg/m3 (0.000022 grain/ft3) - allowable exposure per day over the course of 1 year
- 150 μg/m3 (0.000022 grain/ft3) - allowable exposure over 24 hours
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One of the most popular system that removes all of the above particles from your drinking water (if they are present), is a 5 stage reverse osmosis water purifier that you can install under your sink at home. There are also whole-house systems and water softeners. Email us for more information.  