The size of dust particles, pollen, bacteria, virus and many more. 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

Explore our particle size chart to understand the sizes of dust, pollen, and other airborne particles for improved air quality control.

Dust particles range in size from 1 to 400 micrometers (μm; 1 μm = 0.001 mm [about 0.00004 inch]). Particles larger than about 100 μm (0.1 mm [0.004 inch]), which is about the width of a human hair, are visible to the unaided eye.

Jun 20, 2024 · Particles of sand and large dust, which are larger than 10 micrometers, are not regulated by EPA. EPA’s national and regional rules to reduce emissions of pollutants that form PM will help state and local governments meet the Agency’s national air quality standards.

Apr 7, 2022 · Why does dust particle size matter? Particles that are too small to see do the most damage because they can actually get into our bodies. Our lungs have evolved to resist parasites and pathogens that we might inhale by catching them with hairs called alveoli that are covered in …

Most dust particles are 5 microns or less, which are so small that they can’t be seen and tend to remain suspended in air for so long that only HEPA filters can take them out. This means that for every piece of dust you see floating in the air there are 9 more that are too small for you to see.

More commonly, however, dust are those particles between 1 and 100 micrometers (10 −6 m). Three thirds of the sources determined the diameter of a speck of dust to be a small number and/or a range, but one source referred to the diameter as specifically 254 micrometers.

Particle: Particle Size (Microns) postage stamp (1 inch) 25,400: beach sand: 100-2000: eye of a needle: 1230: pollens: 10-1000: saw dust: 30-600: coffee

Essentially, what we think of as dust can be made up of dozens, even hundreds of different airborne particles. This means household dust can have a massive particle size distribution. In most homes, household dust will range from as little …