Overview: From the perspective of pollution from toxic fine particulate matter (PM2.5), Kingston’s air quality for the first eight months of 2026 was 6.6 µg/m3, moderately worse than the average of the previous six years. That is 31% above the WHO-recommended limit of 5.0 µg/m3 and, as you can see from the chart on our Health Impacts page, well above the threshold for causing increased mortality among Kingstonians. Kingston’s PM2.5 levels had exceeded that limit in 58 of the past 80 months, often much worse. Smoke from Western and Northern Canada wildfires was a significant factor for a few of those days but, as usual, most of the toxins which we were breathing came from US emissions (both heavy-industry emissions and an unprecedented number of southeastern US wildfires, exacerbated by deep budget cuts to US firefighting capabilities). Given that we have absolutely no levers to influence US-generated pollution, all we can do is to limit how much gets into our lungs by taking some of the measures suggested in our Self-Protection page. Do you know others who might benefit from more awareness of the reality of our air quality and how they can better protect their health? If so, please share this link: https://kingstonairquality.ca.
by Ron Hartling
The purpose of this site is to raise awareness of the uncomfortable reality that, with respect to fine particulate matter (PM2.5), Kingston air quality is consistently worse than the World Health Organization (WHO) standard. The site gives practical advice on managing household exposure to health-damaging particulates. Updates are posted daily around 7 am but the satellite view below shows the current Kingston reading at any time of day. If you live elsewhere, just click at your location on the map. For ease of personal decision-making, overall daily risk levels are categorized by severity in the table to the right.
Note that, while most Canadian and US sources define Risk Level 1 as airborne fine-particulate-matter (PM2.5) concentrations less than 12 micrograms per cubic meter (µg/m3), I employ “Level 0” to differentiate readings within the far more evidence-based, less politically-influenced WHO healthy zone. Click on the Health impacts page for clarification on the critical differences between short- and long-term exposure risks.
Commentary as of Friday September 25 at 6:25 am
Yesterday’s readings: Kingston’s hourly PM2.5 readings again remained reasonably healthy yesterday, between 2 and 4 µg/m for a daily average of 3.1 µg/m3. That was essentially unchanged from Wednesday’s 3.0. Overnight readings rose to 6 µg/m3.
Forecast for today: Readings will likely fluctuate within the moderately-unhealthy Level-1 range.
Detailed forecast: Environment Canada’s 24-hour Kingston forecast calls for continuing northeasterly winds for the entire period. The high-altitude Jetstream will again be absent from our region. As you can see from the satellite view, that means that the moderate Level-1 particulate cloud to our northeast will be coming our way.
Personal protective measures: No such measures should be needed either today or tomorrow.
Please note: Due to my being on the road for most of Saturday and Sunday, there will be no updates either day.
As of 6:15 am, this satellite view of PM2.5 fine particulate flows over North America showed further worsening of continental air quality compared to yesterday at the same time, with much of the continent under unhealthy Level-2 clouds of mostly US-generated particulates. Eastern Ontario was at the Level-1 fringe of one of those clouds.
Summary of Recent Readings
This table summarizes and provides context for the most recent three weeks of Kingston PM2.5 airborne fine particulate readings. The key numbers are, of course, the daily averages because that’s what informs us how our recent exposures have contributed to or ameliorated whatever annual exposure to toxic particulates we are comfortable with or accepting of. For those who choose to lower their at-home exposure in order to better protect their and their households’ long-term health, the numbers provide important information on how much effort may be required to stay within their comfort levels.
To facilitate that analysis, the table also computes each day’s risk category (usually a mix of 0’s, 1’s and 2’s), as well as 7- and 28-day running averages and medians. It also reports on the minimum and maximum readings for each day, as well as on the number of hours that day during which Kingston PM2.5 readings may have exceeded either or both the World Health Organization’s recommended maximum and the seriously outdated and therefore misleading US/Canadian equivalent.