Particulate matter or PM is often included in air quality news and reports for environmental authorities and organizations. But, what exactly is particulate matter and why should we be concerned about it?
Particulate matter is a complex mixture of solid and liquid particles suspended in the air. PM may contain carbon, organic chemicals, sulfate nitrates, sodium chloride, dust, water, and a range of metals. Common sources include emissions from vehicles, factories, construction activities, tobacco smoke, laser printers, and some types of VOCs released by perfumes and cleaning products. PM may vary greatly in size but researchers divided them into three categories for regulation and monitoring purposes:
- Ultra fine: <0.1µm in diameter
- Fine: 0.1 to 2.5µm in diameter
- Coarse: between 10µm and 2.5µm in diameter
Low concentrations of particulate matter may still be considered safe, but being exposed beyond its permissible levels can bring serious problems on health.
The effects of particulate matter on health depend on its size and classification. Particles that are less than 10µm can pass through the nose and throat. These can enter the lungs and go on deeper parts of the respiratory tract causing damage to the tissues and inflammation. PM2.5 can cause eye and nose irritation, coughing, sneezing, and difficulty breathing. It can also intensify existing diseases such as asthma, heart problems, and bronchitis.
Additionally, one of the studies from Harvard University has also confirmed that prolonged exposure to particulate matter, particularly PM2.5 can lead to an 8% increase in the number of COVID-19 deaths.
What’s the best way to measure PM?
PM can’t be easily detected without an instrument, and the use of indoor air quality monitoring devices that measure the presence and levels of air pollutants, including PM is highly advisable. PM sensors use a light scattering principle to measure the concentration of particles in the air. This works by passing air through an optical chamber and using a laser beam to scatter the suspending particles of varying sizes onto a photodetector, which counts and calculates the particle size based on the amount of light deflected.
PM sensors can be used to:
- Raise awareness and increase people’s understanding of particulate matter and its impacts
- Monitor the exposure of people who are more vulnerable to illnesses linked to air pollution
- Discover existing air quality problems and prevent its potential effects on health
- Comply with health standards and green building certifications such as Fitwel, LEED, and WELL.
Curious about the PM levels of particulate matter in your workplace?