"The U.S. EPA classifies and regulates dust, smoke, and soot by particle size. The particle size is measured in microns. Dust or PM less than or equal to 10 microns in diameter is commonly referred to as PM10. Most dust associated with crushing facilities falls into this category. Finer sources of PM equal to or smaller than 2.5 microns (PM2.5) are typically a result of photochemical reactions. Research has shown that inhaling too much dust lowers the body’s natural defenses because dust builds up in our respiratory system and irritates the sensitive tissues in our lungs. Therefore, breathing a lot of dust over a long period of time can cause chronic breathing and lung problems. Another consequence of dust generation is reduced visibility (also known as haze).; Haze can contribute to excessive soiling, discoloration, and damage to personal property. Fine particles can remain suspended in the air and travel long distances. For example, emissions from a factory in Gary, Indiana, can end up in Grand Rapids, Michigan. The crushing of nonmetallic minerals is just one of a number of dust-generating activities regulated by the U.S. EPA and EGLE" from Michigan Environmental Compliance Guide for Nonmetallic Mineral Crushing Facilities
This video was shot by a family in Western Wisconsin. They were driving down a county road, past a frac sand mine, when they saw this. When new frac sand mines open, there's always a discussion about silica dust, because it's a carcinogen. Mine developers are usually quick to point out that dust isn't ever a public health problem, because the sand is either kept contained or kept wet, or both.
"The Pit owner came and talked to my wife and I and assured us he would mitigate the dust. He shook our hands when he left. Not once were any measures taken to control the dust or noise. "
video from a neighbor of the gravel mine in Grass Lake Michigan