Delhi's air quality continues to remain in the 'moderate' category. According to the Central Pollution Control Board, Delhi recorded an Air Quality Index of 171  at 4 AM this morning.<br />'' <br />''<span style="color: #222222;">The national capital's AQI was 435 on Sunday and 414 on Saturday. An AQI between 0 and 50 is considered good, 51 and 100 satisfactory, 101 and 200 moderate, 201 to 300 poor , 301 to 400 very poor and 401 to 500 severe. </span><br />