U.S., Nov. 21 -- AirAsia India , one of India's budget carriers, has expanded the range of masks available on board and started to hand out the anti-smog masks, free of charge, to those traveling to Delhi from large cities like Bengaluru, Hyderabad, Mumbai, and Kolkata.

The air in the Indian capital is so toxic that deadly particles - known as PM 2.5 - can reach deep into the lungs, causing cancer and the masks are supposed to help cope with toxic level smog in the capital.

Now, masks will help passengers to protect themselves from pollution even after the flight, the airline said, adding that the innovation is about giving passengers "the best in-flight experience."

The campaign, however, is limited in scope as it is set to run until ...