Environmental Air Testing Laboratory SanAir recommends
residents change air filters in cars and homes when Particulate Matter (PM) such as PM2.5 and PM10 health threats subside
Canadian wildfire smoke is creating unhealthy to hazardous air quality conditions at ground level across the Midwest and parts of the Northeastern United States. Various state environmental agencies in Michigan, Ohio, Indiana, New York, New Jersey, among others, issued warnings to residents on July 16, 2026, regarding an emergent health threat from inhalable particulate matter (PM) due to the impact of heat and smoke from wildfires. PM2.5 warnings typically arise from wildfire smoke and other combustion sources, such as vehicle exhaust.
Why is PM2.5 So Dangerous to Humans?
What makes PM2.5 particularly insidious and dangerous is the size of the particle.
According to the EPA, PM2.5 consists of “… fine inhalable particles, with diameters that are generally 2.5 micrometers and smaller. How small is 2.5 micrometers? Think about a single hair from your head. The average human hair is about 70 micrometers in diameter – making it 30 times larger than the largest fine particle.”
The minute particle size allows PM2.5 to remain suspended in the air longer and penetrate further into the lungs and tissues, making it harder to expel. At greatest risk for immediate complications from PM2.5 hazardous days are the elderly and individuals with chronic lung issues, but long-term impacts can be significant for healthy populations. Reference: https://www.epa.gov/pm-pollution/particulate-matter-pm-basics
When PM Levels Are High, Stay Inside
The most important step to protecting yourself from high PM2.5 and PM10 threat days is to be aware when warnings are issued. AirNow’s website, https://www.airnow.gov/wildfires/, allows users to check local air quality levels on a zip code-basis. There are also apps available that will push notifications out to users when air quality levels are becoming hazardous. When you get that notification, do your best to stay inside with the windows closed until the threat passes. If you must go out, limit your exposure. Even those without conditions like asthma and emphysema can have serious, long-term effects from chronic exposure. To protect the air quality in your indoor environment, consider investing in a high-efficiency particulate air (HEPA) filter. A National Institutes of Health study confirmed that they can be effective at removing PM2.5 particles from indoor air. Reference: https://pmc.ncbi.nlm.nih.gov/articles/PMC9516965/
Change Air Filters When the Threat Passes
To keep HVAC systems, HEPA filters and in-cabin car air systems working effectively, be sure to change air filters when the threat passes.
Testing for PM2.5 and PM10
SanAir’s specialty environmental division, formerly known as Centek Labs, has extensive environmental testing capabilities in air (including VOCs; soil vapor intrusion; LEED®, WELL®, IAQP, and IgCC® certification systems; biogas; and industrial hygiene). Our laboratory regularly performs volatile organic compound (VOC) testing using canister technology, as well as testing via pump attached to a filter to determine the PM2.5 fine particulate levels. SanAir’s Material Science Testing division helps clients uncover the origin of fires (including wildfires), material failures, and insurance claims. We have extensive experience assisting with both qualitative and quantitative analyses to identify sources of origin and fire characteristics, and often support investigative efforts to identify sources of product failure or contamination.