Delhi’s air quality in moderate category, overcast weather expected

An AQI between zero and 50 is considered “good”, 51 and 100 “satisfactory”, 101 and 200 “moderate”, 201 and 300 “poor”, 301 and 400 “very poor”, and 401 and 500 “severe”

Delhi’s air quality was in the moderate category on Friday morning as overcast weather is expected with the mercury likely to hover around 39 degrees Celsius.

(HT PHOTO)

The hourly air quality index (AQI) was 175 at 7 am. On Thursday, the average 24-hour AQI was 140 in the moderate category. The air quality is likely to be within the “moderate” or upper end of the “satisfactory” categories for the next three days.

An AQI between zero and 50 is considered “good”, 51 and 100 “satisfactory”, 101 and 200 “moderate”, 201 and 300 “poor”, 301 and 400 “very poor”, and 401 and 500 “severe”.

Monitoring agency the System of Air Quality and Weather Forecasting And Research said PM10 was the primary pollutant on Thursday. “...dust size > 2.5 micrometer contributes 60% to PM10. For the next 3 days (24th, 25th, 26th) peak wind speed is likely to be 15-20 km/h causing moderate dispersion and AQI is likely to be within ‘moderate’ or ‘upper end of satisfactory’. Moderate temperature (38 deg C) and mixing layer height (2.5 km) is going to maintain moderate ventilation by convection improving air quality.”