Air quality in Ichihara, Japan today

Mr. Duck’s Air Quality Score

Good air today for Ichihara, 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 Ichihara is currently classified as Good. The primary pollutant identified is PM2.5 (fine particles), with a measured concentration of 9.0 µg/m³. A total of 30 valid measurements support this assessment, and the data are shown via OpenAQ.

Overall conditions meet the criteria for a Good rating based on the available observations. 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 Ichihara air‑quality dataset currently contains seven monitoring locations that together provide 35 recent observations across six key pollutants: carbon monoxide (CO), nitrogen oxide (NO), nitrogen dioxide (NO₂), total nitrogen oxides (NOX), fine particulate matter (PM2.5) and sulfur dioxide (SO₂). All of the most recent readings were recorded at the same site, 市原市北国分寺台３－５－１, with the latest timestamp of 2026‑02‑10 22:00 UTC, which falls within the three‑day freshness window used for the feed. Because every pollutant’s last update shares this date and time, the data can be considered uniformly current for the city at that moment.

The measured values show a fairly narrow spread for most gases. CO is reported as a single value of 0.2 ppm, with no variation across the seven rows. NO registers a minimum of 0.0 ppm and a maximum of 0.007 ppm, while both NO₂ and NOX range from 0.003 ppm up to about 0.033–0.04 ppm; their median values are identical at 0.013 ppm, indicating that typical concentrations hover around this level. Sulfur dioxide is similarly low, ranging from 0.0 to 0.013 ppm with a median of 0.0005 ppm. Particulate matter shows the greatest variability: PM2.5 values span 5.0 to 26.0 µg/m³, with a median of 7.0 µg/m³ and the 10th‑percentile at 6.2 µg/m³ versus the 90th‑percentile at 16.4 µg/m³, suggesting that while most measurements are modest, occasional higher readings do occur.

Overall, the dataset offers complete coverage of the six listed pollutants but is limited to a single monitoring address, meaning spatial variation within Ichihara cannot be captured. The uniform freshness of the timestamps ensures the snapshot reflects conditions on 2026‑02‑10, yet users should keep in mind that air quality can differ across neighborhoods and over time, so additional measurements would be needed for a more detailed citywide picture.

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 Ichihara includes 30 valid measurements and is Updated within 3 days, with the most recent values recorded at 2026‑02‑10T22:00:00+00:00. These figures represent a snapshot of ambient conditions across the city; actual air quality can differ by specific location and time of day, so users should consider local variations when interpreting the data.

OpenAQ station rows