Overview: 2026 began with a few days of relatively clean air, followed by three quite toxic days and then a roller coaster of healthy, moderately unhealthy and quite unhealthy days for the remainder of January. Quite literally, it all depended on which way the winds were blowing. Days dominated by northerly winds had clean air and those with airflows coming from the USA were to a greater or lesser degree comparatively toxic. Our monthly average was 7.0 µg/m3, making it the second-worst January in the past seven years. That average dangerously exceeded both the WHO limit and the 5.8 µg/m3 threshold beyond which, as you can see on our Health Impacts page, excess mortality begins to soar. PM2.5 levels have now exceeded the WHO limit in 53 of the past 73 months! Your actual exposure may be considerably less depending on the precautions you choose to take. 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 Thursday February 12 at 6:30 am
Yesterday’s readings: Kingston’s PM2.5 readings were terrible in the early morning hours , up to 33 µg/m3 (Level-3) but plummeted around 8 am and remained mostly at healthy Level-0 values for the rest of the day. That yielded a daily average of 10.2 µg/m3, up from Tuesday’s 8.3. Overnight readings held constant at 3 µg/m3.
Forecast for today: Kingston readings should remain within healthy Level-0 values today and hopefully into tomorrow
Detailed forecast: Environment Canada’s 24-hour Kingston forecast calls for moderate northwesterly winds over the entire period. That’s consistent with the northwesterly component of the Jetstream passing to our south. As you can see from the satellite view, we are continuing to benefit from the influx of clean northern air.
Personal protective measures: No such measures should be needed either today or tomorrow.
As of 6:15 am, this satellite view of PM2.5 fine particulate flows over North America showed yet another massive cloud of heavy-industry particulate emissions building up over most of the eastern half of the USA. At this early stage in the usual cycle, the concentrations are already quite unhealthy, but no more than Level-2. Eastern Ontario continues to be protected by a northwesterly flow of comparatively clean artic air.
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.