Air quality in Narashino
The air quality index in Narashino is currently 25 — good. The pollutant driving that figure is O₃.
Updated 11:00
Current pollutant concentrations
| Pollutant | Concentration | Sub-index | Level |
|---|---|---|---|
| PM2.5Fine particles under 2.5 µm, small enough to reach the bloodstream. | 6.1 µg/m³ | 25 | Good |
| PM10Coarse particles under 10 µm from dust, pollen and combustion. | 13.3 µg/m³ | 12 | Good |
| NO₂Nitrogen dioxide, mostly from traffic and heating; aggravates asthma. | 15.2 µg/m³ | 8 | Good |
| SO₂Sulphur dioxide from fuel combustion; irritates the airways. | 9.2 µg/m³ | 5 | Good |
| COCarbon monoxide; reduces the blood’s ability to carry oxygen. | 148.4 µg/m³ | 1 | Good |
| O₃Ground-level ozone, formed in sunlight; causes breathing difficulty. | 67.8 µg/m³ | 31 | Good |
Next 24 hours in Narashino
Over the next 24 hours the index is forecast to range between 15 and 33, peaking around 15:00.
Narashino Air Pollution – Real‑time AQI
Fine particulate matter ≤ 2.5 µm – penetrates deep into lungs & bloodstream.
Coarse particulate matter ≤ 10 µm – causes respiratory irritation.
Nitrogen dioxide – aggravates asthma, lowers immunity to infections.
Sulphur dioxide – irritates eyes, nose, throat; forms harmful aerosols.
Carbon monoxide – reduces oxygen delivery to organs & tissues.
Ground‑level ozone – triggers breathing difficulty & throat irritation.
About This Air Quality Data
Data Source
Real-time air quality measurements are provided by OpenWeatherMap's Air Pollution API, which aggregates data from multiple ground-based monitoring stations worldwide. The data is updated hourly to ensure accuracy and timeliness.
AQI Calculation Method
The Air Quality Index (AQI) is calculated using the United States Environmental Protection Agency (US EPA) standard methodology. This involves:
- Converting raw pollutant concentrations (PM2.5, PM10, NO₂, SO₂, CO) to individual AQI values
- Using EPA-defined breakpoint tables for each pollutant type
- Taking the maximum individual AQI as the overall AQI (dominant pollutant approach)
- Applying unit conversions: CO (ppm), NO₂ and SO₂ (ppb) from µg/m³
Note: AQI values are indicative and should be used for general awareness. Sensitive groups (children, elderly, those with respiratory conditions) should take extra precautions when AQI exceeds 100.
What this means for you
Air quality is satisfactory and poses little or no risk. Normal outdoor activity is fine for everyone.
How the air quality index is scored
| Index | Level | What it means |
|---|---|---|
| 0–50 | Good | Air quality is satisfactory and poses little or no risk. Normal outdoor activity is fine for everyone. |
| 51–100 | Moderate | Air quality is acceptable. People unusually sensitive to air pollution may want to limit prolonged exertion outdoors. |
| 101–150 | Unhealthy for sensitive groups | Children, older adults and people with asthma or heart disease should reduce prolonged or heavy exertion outdoors. |
| 151–200 | Unhealthy | Everyone may begin to feel effects. Reduce prolonged exertion outdoors; sensitive groups should stay indoors where possible. |
| 201–300 | Very unhealthy | Health alert. Avoid outdoor exertion and keep windows closed. Sensitive groups should remain indoors. |
| 301–500 | Hazardous | Emergency conditions. Everyone should avoid all outdoor activity and stay indoors with filtered air. |
How this figure is produced
These values come from the Copernicus atmospheric model as distributed by OpenWeather, sampled at the coordinates of Narashino. They are modelled concentrations on a grid, not readings from a monitoring station inside the town, so neighbouring localities in the same grid cell will show similar figures. Treat them as a regional indication rather than a measurement taken at your street.