The Airports Authority of India (AAI) has announced that 4 Indian airports have received international recognition forreducing the carbon emission level as per the standards set by Airports Council International (ACI) for the grading. The 4 airports are as follows: Netaji Subhas Chandra Bose International Airport (West Bengal) Biju Patnaik International Airport (Odisha) Lal Bahadur Shastri International Airport (Uttar Pradesh) Trivandrum International Airport (Kerala)