VARANASI: The city's air quality moved into the Good category on Friday, October 30, 2026, with a Central Pollution Control Board AQI of 30 at 16:00 IST, compared with 79 a day earlier. This is a new reading after the Moderate category as reported earlier on dalimss.news. All four monitoring stations contributed to Friday's bulletin.
For residents planning outdoor work or a journey around BHU, Maldahiya and other city localities, the improvement is welcome, but the figure needs its date and averaging period attached. It is the October 30 city summary, not a fresh measurement from an individual street on Saturday morning. Check a current station reading before treating the number as a description of conditions at a particular place.
CPCB labels the Good band as having minimal health impact. Friday's value was 49 points below Thursday's, and the category changed from Satisfactory to Good. This is a change in an index, not evidence that the concentration of every pollutant fell by the same proportion.
What changed in the two daily bulletins
The October 30 official bulletin lists PM10 and sulphur dioxide, shown as SO2, as Varanasi's prominent pollutants. The October 29 bulletin lists PM10 alone. The prominent pollutant column identifies the pollutants associated with the index; it does not give their concentrations in that row.
| Bulletin time, IST | AQI | Category | Prominent pollutants | Stations |
|---|---|---|---|---|
| October 29, 16:00 | 79 | Satisfactory | PM10 | 4 of 4 |
| October 30, 16:00 | 30 | Good | PM10 and SO2 | 4 of 4 |
Both summaries therefore include the full listed station count. Thursday's Satisfactory category covers values from 51 to 100; Friday's Good category covers 0 to 50. CPCB associates the Satisfactory band with possible minor breathing discomfort for sensitive people. The newer result crosses that category boundary rather than merely moving within the same band.
How to read a city AQI number
CPCB's bulletin says that cities with several monitoring locations are represented by an average. Its note explicitly cautions that air quality can differ between locations and that averaging is used for simplicity. The Varanasi row does not supply a separate value for each neighbourhood, so it cannot establish that every part of the city had an AQI of 30.
The board's calculation guidance explains another distinction. At a monitoring location, individual pollutant sub-indices are calculated from average concentrations and health breakpoints. The highest sub-index determines that location's AQI. The overall number is consequently not a sum of pollutant concentrations.
The method generally uses 24 hour averages, with eight hour averages for carbon monoxide and ozone. Calculating an overall AQI requires data for at least three pollutants, including either PM10 or PM2.5. A minimum of 16 hours of data is needed to calculate a pollutant sub-index. These requirements explain why a station's participation matters alongside the headline value.
The National Air Quality Index information page also links the board's explanation of running averages. A value displayed at a particular hour draws on preceding observations. It should not be read as an instantaneous sample of the air at that minute, or as a forecast of what the following day will bring.
CPCB also publishes limitations of its real time index. It says incoming readings are supplied without scrutiny and may not be suitable for statutory purposes. Maintenance problems or interruptions to station operation can disrupt the data flow. Readers comparing future bulletins should check the participating station count as well as the index value, rather than interpret an absent reading as clean air.
What residents should do
Use the date, time and location together when checking or sharing AQI information. CPCB's bulletin archive allows readers to compare like daily summaries, while the national index page links to current monitoring information. A later value should replace this dated summary when making a fresh assessment.
Weather and air quality require separate checks. Our earlier rain forecast revision report and farm advisory on harvested paddy and wet fields provide dated background. The AQI bulletin itself does not attribute Friday's improvement to rain or any particular source of pollution.
