India, May 31 -- The Delhi government has mandated the installation of rooftop anti-smog guns in all high-rise commercial, hotel, and institutional buildings across the city, in a unique directive aimed at tackling urban air pollution.

The order, issued by the environment department on May 29, applies to commercial complexes, malls, and hotels with a built-up area greater than 3,000 square metres, and to office and institutional buildings that are at least ground plus five floors tall.Residential houses, apartment complexes, and group housing societies have been exempted.

"The directive applies to all commercial complexes, malls, and hotels with a built-up area greater than 3,000 square metres, as well as all institutional and office bu...