Delhi's air quality remained in the ‘poor' category on Wednesday, according to System of Air Quality and Weather Forecasting And Research (SAFAR).
The Air Quality Index (AQI) was 249 as against 215 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 105 in the 'poor' and 197 in the 'moderate' category respectively.
Earlier, Delhi received light showers on Saturday due to which the air quality in the national capital improved for the next two days.
Meanwhile, the air quality in Noida remained in 'moderate' category with AQI at 186 while in Gurugram, the air quality was comparatively better with AQI at 97.
However, the air quality in Pune, Mumbai and Ahmedabad was in 'satisfactory' category.
As per the government agencies, 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'.

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