As per CPCB data, Hassan in Karnataka had the best Air Quality Index at 25 today. A total of 17 cities fell into the category of 'Good' air quality including Aizawl, Bagalkot, Chikkaballapur, Chikkamagaluru and Ernakulam. Hubballi, Mangalore, Madikeri, Naharlagun, Puducherry, Shillong, Shivamogga, Srinagar, Thiruvananthapuram, Thrissur and Tirupati were also on the list.