New Delhi, Oct 26 : The air quality in the national Capital continued to remain in the Poor category as the overall Air Quality Index (AQI) of the city reached 256 on Thursday morning, according to data from the System of Air Quality and Weather Forecasting And Research (SAFAR). The AQI at Dhirpur with PM 2.5 was at 307, under a very poor category. The 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'. In Pusa, the AQI recorded PM 2.5 at 221 'poor category'. At Lodhi Road, the Air Quality Index with PM 2.5 concentration was at 225 under the poor category and the PM 10 stood at 161 also under the moderate category. At IIT Delhi station the PM 2.5 was at 256, poor category while the PM 10 reached 161, in moderatecategory. The Air Quality Index at the city's Mathura Road was under moderate category with PM 2.5 at 169 with PM 10 concentration at 156. According to the forecast from the SAFAR, the air quality of the city will deteriorate further under poor category with PM 2.5 reaching 293 and the PM 10 concentration at 174 under 'moderate category' on Friday. The Air Quality Index of Delhi's neighbouring cities of Noida stood at 269 and the PM 10 concentration at 263 both under poor category, while Gurugram's AQI was reported at 176 and the PM 10 concentration at 136 under moderate category. /IANS