Measuring Air Quality During Wildfires

Monitoring air quality is crucial for maintaining the safety of the population during wildfires. Although a proper air quality measurement requires several calculations, monitoring one of the parameters contributing to air quality can be a useful indicator. One such parameter is PM_2.5.

The Dangers of Wildfire Smoke

Wildfire smoke contains a number of contaminants. Of these contaminants, the one that is the most harmful to human health is fine particulate matter (PM_2.5). PM_2.5 particles are 2.5 microns or less in diameter. For air pollution, the size of particles has a significant effect on the damage they can cause. The smaller the particle, the larger impact it can have on human health. Because they are so small, PM_2.5 particles can travel deep into the lungs if inhaled. Then, these particles can cause irritation and inflammation throughout the body.

Wildfires produce smoke with high amounts of PM_2.5, and this smoke can linger for as short as a few hours or as long as a few weeks. This smoke can consist of other various gases that can also have an impact on air quality and human health. One type of gas in smoke is volatile organic compounds (VOCs), which evaporate quickly. When produced in large quantities, these VOCs can aggravate the eyes, nose, throat, and lungs. Other gases in wildfire smoke that can cause irritation include:

• Nitrogen Dioxide (NO₂)
• Sulphur Dioxide (SO₂)
• Ozone (O₂)

Air Quality and PM_2.5

While a number of factors go into determining the air quality index (AQI), a strong correlation exists between PM_2.5 and AQI. Based on this correlation, measuring the mass density of particles can help determine the air quality. AQI is calculated to educate the population of an area on the air quality so they can safeguard their health.

To calculate AQI, you need a table of specific values and a complicated equation. However, for a general indication of air quality instead of a specific AQI measurement, PM_2.5 is a good gauge. Generally, the higher the concentration of PM_2.5, the higher the likelihood the AQI measurement is high and the more dangerous the air is.

Counting PM_2.5 Particles

The easiest way to monitor particle concentrations of PM_2.5 is to use a particle counter. Setra's particle counters are designed to monitor both particle counts and VOCs. Our particle counters can measure particles as small as 0.3 microns and provide multiple particle size readings at once. For a detailed picture of particle concentrations and total VOCs in the surrounding air, check out all of Setra’s particle counter offerings.