Air quality in Katsushika, Japan today

Mr. Duck’s Air Quality Score

Moderate air today for Katsushika, 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 Katsushika is currently classified as Moderate. The primary pollutant identified for today is PM2.5 (fine particles).

Measurements show a PM2.5 concentration of 21.0 µg/m³ based on eight valid observations reported through OpenAQ. 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 Katsushika pulls in four measured pollutants – nitrogen monoxide (NO), nitrogen dioxide (NO₂), total nitrogen oxides (NOX) and fine particulate matter (PM2.5). The information comes from two monitoring sites, giving a total of eight recent rows of data. All readings were last updated on 2026-02-10 at 22:00 UTC, which means the freshest values are less than three days old across every pollutant.

For NO the recorded values span from a low of 0.004 ppm to a high of 0.020 ppm, with a median of 0.012 ppm and the middle 80 % of observations falling between roughly 0.0056 ppm (10th percentile) and 0.0184 ppm (90th percentile). NO₂ shows a tighter band, ranging only from 0.029 ppm to 0.031 ppm; its median is 0.030 ppm and the 10th‑to‑90th percentile window is 0.0292–0.0308 ppm. NOX values are broader, extending from 0.033 ppm up to 0.051 ppm, with a median near 0.042 ppm and an inter‑percentile spread of about 0.0348–0.0492 ppm. PM2.5 concentrations sit between 19 µg/m³ and 21 µg/m³, the median is exactly 20 µg/m³, and the central 80 % of measurements range from 19.2 to 20.8 µg/m³.

The data set therefore offers a complete snapshot for each of the four pollutants at two locations, all captured within the same recent time window. While the number of stations is limited, the values show modest variability: NO and NOX exhibit wider ranges than the more stable NO₂ and PM2.5 readings. Because only two sites contribute, conditions elsewhere in Katsushika may differ from what these points record at any given moment.

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 eight valid measurements and was refreshed recently, with the latest update recorded on 2026‑02‑10 at 22:00 UTC; it is considered “Updated within 3 days.” This snapshot provides a brief view of current conditions, but air quality can differ across neighborhoods and change throughout the day, so local variations may not be captured in these figures.

OpenAQ station rows