PM10 or coarse dust particles refer to
particles with a diameter less than or equal
to 10 microns in size. They are about 30
times smaller than the width of a human
hair and are small enough to evade our
defensive nose hairs and get inhaled into
our lungs. Sources of this PM10 include
crushing/grinding operations, and dust
stirred up by vehicles. Pollen, mold, and
plant and insect particles are also
considered PM10. Finally, the evaporation
of sea spray can also produce large
particles in coastal areas.
Dangerous level: 125 µg/m3 (microgram
per cubic meter) or more.
PM2.5 or fine particles are 2.5
micrometers in diameter or smaller. Fine
particles are produced from all types of
combustion, including motor vehicles,
power plants, residential wood burning,
wildfires, agricultural burning, and some
industrial processes. While PM10 ends up
in your lungs, PM2.5 is more dangerous as
it can transfer from your lungs into your
bloodstream. From your bloodstream, it
can it end up anywhere in your body,
thereby making it "the invisible killer".
Dangerous level: 90 µg/m3 or more.
PM1 – particulate matter with a diameter
smaller than 1 micron – is a major subset
of PM2.5. These are extremely fine
particles that are even more likely to reach
How do particles affect the human body?
deeper into the respiratory system than
PM2.5. PM1 is the by-product of emissions
from factories, vehicular pollution,
construction activities, and road dust. It is
not dispersed and stays suspended in the
air that you breathe.
Dangerous level: 61 µg/m3 or more.
THE SMALLER THE PARTICLES,
THE MORE DANGEROUS THEY ARE
We’re sure you have heard about air pollution. It’s a major issue worldwide today and
is mostly caused by very small particles in the air known as particulate matter (PM)
Particulate Matter (PM), also known as soot, is made of microscopic solid particles
or liquid droplets that are either emitted directly into the air or formed by pollutants
that combine in the atmosphere. PM is usually measured in three size ranges, which
are the most harmful to health: PM10, PM2.5, and PM1.
