Air quality in Hofu, Japan today

Mr. Duck’s Air Quality Score

Good air today for Hofu, Japan

⚠️ 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 Hofu is currently classified as Good. The primary pollutant identified is PM2.5 (fine particles). Measurements show a PM2.5 concentration of 7.0 µg/m³, based on five valid observations collected through OpenAQ.

Overall conditions meet the criteria for a Good rating, and no additional pollutants are highlighted in today’s assessment. 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 dataset for Hofu includes five measured pollutants – nitrogen monoxide (NO), nitrogen dioxide (NO₂), total nitrogen oxides (NOX), fine particulate matter (PM2.5) and sulfur dioxide (SO₂). All observations come from two monitoring stations located at 防府市岡村町２－１, together providing ten recent rows of data. Each pollutant’s most recent reading was recorded on 2026‑02‑10 at 22:00 UTC, and the system flags all entries as “Updated within 3 days,” indicating that the latest information is fresh across the board.

The NO values are uniformly zero (0.0 ppm) for every row, showing no detectable presence during the sampling period. By contrast, NO₂ and NOX show a very narrow band of concentrations, ranging from 0.005 ppm to 0.006 ppm with median values of 0.0055 ppm; this tight spread suggests stable readings across the two stations. PM2.5 displays a broader range, with the lowest observed level at 7.0 µg/m³ and the highest at 38.0 µg/m³, while the median sits at 22.5 µg/m³. The 10th‑percentile (10.1 µg/m³) and 90th‑percentile (34.9 µg/m³) illustrate that most measurements fall between roughly ten and thirty‑five micrograms per cubic metre. SO₂ is largely absent, recorded at 0.0 ppm in the minimum and rising only to 0.001 ppm at its maximum, with a median of 0.0005 ppm.

Overall, the coverage is limited to two sites but provides a complete set of recent readings for all five pollutants. The data are uniformly current, yet the small number of stations means that conditions elsewhere in Hofu may differ from those captured at 防府市岡村町２－１.

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 data shown reflects five valid measurements and is updated within 3 days, with the latest reading recorded on 2026‑02‑10 at 22:00 UTC. While this snapshot provides a current view of Hofu’s air quality, conditions can differ across neighborhoods and change throughout the day, so individual experiences may vary from the values presented here.

OpenAQ station rows