PM0.3 Explained

Particulate matter (PM) is a term used to refer to a complex mixture of solid particles and liquid droplets floating in the air we breathe.  Car exhaust, smoke from wildfires, tree pollen, mold spores, animal dander, dust from construction sites, and even droplets carrying germs (bacteria and viruses) - these are some examples of PM sources that we are exposed to regularly.  Particles from these sources mix together in the air to form the most dangerous kinds of air pollution.

To fully understand PM and its impact on the air we breathe, one needs to break things down by size.  PM is measured by its diameter in microns (also called micrometers or abbreviated by μm).  Microns are invisibly small.  To put this in perspective, the diameter of a human hair can be up to 100 microns, and a single red blood cell is about 8 microns. Dangerous air pollution particles are even much smaller!

Common PM measurements for air pollution that you may have seen are PM0.3, PM1, PM2.5, PM5, PM10.  These can be confusing, but for the average person worried about their health in polluted areas, you only need to know PM2.5 and PM0.3.

What are PM2.5 and PM0.3?

PM2.5 are particles 2.5 microns in diameter or larger, while PM0.3 are particles as small as 0.3 microns (PM0.03-PM2.5).  The 0.3 micron mark is the lower size limit for air pollution particles that are most hazardous to your health. They are so tiny that they are absorbed directly into the bloodstream and organs (heart, brain, lungs) when inhaled.  Remember how big a red blood cell is? PM0.3 is more than 25x smaller.  Inhaling PM0.3 is like injecting little bits of soot, germs, dust, and metals into your blood and depositing it around your body.

Various sized particle examples from 2.5 to 0.3 Microns

It’s easy to brush off warnings about the long-term effects of PM such as increased risk for heart attacks, stroke, and by association, death since those problems are down the road. However, a recent study found that short-term exposure to PM2.5 increased inflammation in blood vessels in young adults after only 2 days! Inflammation and narrowing of blood vessels can cause all sorts of discomfort from headaches to chest pain.

Why is PM0.3 so important?

PM0.3, also known as the “Most Penetrating Particle Size,” (MPPS) has the highest chance of success in penetrating most mask filters.  Aside from the typical air pollutants described above, some of the more recently identified pathogens get air-borne thanks to tiny droplets as small as 0.3 microns, which can be easily inhaled if not for PM0.3 filters. 

Think of PM0.3 as the worst-case scenario for a mask. United States NIOSH standards for respirator masks require that tests use the PM0.3 size for measuring filter efficiency. An N95 mask is able to filter at least 95% of particles 0.3 microns in size.

Therefore, it is important to look for masks that use PM0.3 as a standard for their filter.  Even if not certified as an N95 mask, PM0.3 filters provide a higher chance of filtering the smallest particles that PM2.5 filters cannot.  It should be noted that N95 masks are further tested and certified to provide a high degree of fit and tightly seal out air leaks.  Again, some non-N95 masks provide a better chance of sealing out air leaks around the mask, even if not necessarily tested or targeted for medical use. 

How can CUVU Anti-Pollution masks help?

The 3M filtering material and technology used in making CUVU anti-pollution masks make it ideal for filtering not only PM2.5 but even PM0.3, including particles as small as bacteria and some viruses.  

Click here to shop our selection of CUVU anti-pollution masks