 "Delhi AQI, Delhi, air quality index")
Delhi's air quality remained in the ‘poor' category on Friday, according to System of Air Quality and Weather Forecasting And Research (SAFAR).
The Air Quality Index (AQI) was 280 as against 252 a day earlier, at 8 am.
Readings below 50 are considered safe, while anything above 300 is considered hazardous or 'severe'.
The AQI measures the concentration of poisonous particulate matter PM2.5, which can cause cardiovascular and respiratory diseases such as lung cancer, in a cubic metre of air.
This morning, Delhi's levels of PM 2.5 and PM 10 were recorded at 101 in the 'poor' and 199 in
