Air quality in Ottawa, Ontario, Canada today

Mr. Duck’s Air Quality Score

Good air today for Ottawa, Ontario, Canada

⚠️ This website is currently under active development. Some data may be incomplete or temporarily inaccurate. For health-critical decisions, please verify information through official government or environmental sources.

Categories follow US EPA AQI breakpoints for PM (estimate from latest valid measurements; this project does not compute EPA NowCast/24-hour AQI yet).

This friendly indicator summarizes the latest city readings. For health guidance, please see: EPA AirNow or WHO.

Air quality today

The air quality in Ottawa today is classified as Good. The primary pollutant measured is PM2.5. The observed PM2.5 concentration is 7.0 µg/m³. The measurement series includes 17 individual readings taken across the city. No PM10 value is reported for this period. The PM2.5 level aligns with the reference value of 7.0 µg/m³.

Data is shown via OpenAQ. These values are derived from the OpenAQ platform, which aggregates data from participating monitoring stations. All 17 measurements meet the inclusion criteria for the assessment. The dataset reflects conditions captured during the monitoring period. Data are presented in local time. This page is informational; for health guidance, use official sources such as EPA AirNow or WHO.

Latest sensor values

PM categories follow US EPA AQI breakpoints, shown here as an estimate derived from the latest valid measurements (this project does not compute EPA NowCast/24-hour AQI yet).

What the data includes

The OpenAQ feed for Ottawa, Ontario currently contains 37 data rows collected from six monitoring sites. The dataset includes measurements for fine and coarse particulate matter (PM2.5, PM1, PM10), ozone (O3), nitrogen dioxide (NO2), relative humidity, temperature, and particle count (UM003). Sensors for nitrogen monoxide (NO) and nitrogen oxides (NOX) are listed among the pollutants OpenAQ tracks, but no recent rows for those gases appear in the present collection.

Freshness varies by pollutant. The most recent timestamps are from 2026‑02‑10 22:00 UTC for PM2.5, NO2 and O3, showing that those three parameters have been updated within the last month. PM1, relative humidity, temperature and UM003 were last refreshed on 2026‑02‑03 16:00 UTC, also well within the 30‑day freshness window. In contrast, the PM10 values come from an older record dated 2025‑01‑13 23:00 UTC, and a portion of the rows (12) are marked as “unknown” while five are classified as “old,” indicating that coverage is not uniform across all pollutants.

Across the recent measurements, PM2.5 values range from 0.58 µg/m³ to 39 µg/m³ with a median of about 20.5 µg/m³, while PM1 spans 0.13 µg/m³ to 18.12 µg/m³ and centers near 11.5 µg/m³, illustrating a moderate spread in particulate concentrations. Relative humidity is clustered between 42.5 % and 56.3 % (median ≈ 46 %), and temperature varies from –5.99 °C to 14.69 °C (median ≈ –0.24 °C). The particle count (UM003) shows a wide interval, from 170 particles/cm³ up to 2 124 particles/cm³, with a typical value around 921 particles/cm³. NO2 and O3 are both low‑level gases, each ranging from a few thousandths of a ppm up to 0.017 ppm for NO2 and 0.024 ppm for O3, with medians near 0.0095 ppm and 0.0225 ppm respectively. Because some pollutants have limited recent data and the station distribution is uneven, conditions in Ottawa can differ noticeably across neighborhoods and over short time periods.

Learn more about sources and filtering: About the data.

Trusted references: WHO (Air pollution) · US EPA AirNow · European Environment Agency (Air)

Latest sensor values (bars)

PM categories follow US EPA AQI breakpoints, shown here as an estimate derived from the latest valid measurements (this project does not compute EPA NowCast/24-hour AQI yet).

Data notes

The dataset for Ottawa includes 17 valid measurements and is updated within 30 days, with the most recent update on 2026-02-10T22:00:00+00:00. These values represent a snapshot of conditions across the city; air quality can vary by location and time within Ottawa. Users should consider this variability when interpreting the data.

OpenAQ station rows