Political apathy over the poisonous smog choking New Delhi has led many like businessman Kamal Meattle to take matters into their own hands, with an office building he says pumps air as fresh as from the Swiss Alps.
From the outside, the Paharpur Business Centre looks like any modern office block. But inside, it is a virtual jungle where rooms and corridors are lined with more than 7,000 potted plants and creepers.
The greenhouse terrace, with artificial grass and green walls, houses an "air washing" system that moves polluted outside air through a series of cleaning filters.
It is then pushed through the greenhouse where the plants remove bacteria, fungus, carbon dioxide and other toxins, before the air conditioning pumps it to workers on the floors below.
"It would be like working in Gulmarg in Kashmir or Davos in Switzerland in this building," 73-year-old Meattle said as he looked out at the smog from the protection of the lush rooftop nursery.
"You are actually right now sitting in an air tank," he said, referring to the greenhouse where PM2.5 - the most harmful particulates in the air - registered nearly zero compared with 415 outside, according to Paharpur's monitoring system.
The outside level is more than 16 times the World Health Organisation's safe limit.
A Massachusetts Institute of Technology graduate and trustee of Al Gore's Climate Reality Project, Meattle began thinking about a clean office project years ago when he rejected doctors' advice to move away from the polluted capital for his health.
His centre, whose tenants include Amazon, Samsung and Microsoft, is now rated the city's healthiest building by the Indian government.
Chakr Shield
Fumes from backup generators are a central ingredient in the noxious cocktail, but one company is turning them into ink and paint with technology that can capture up to 90% of dangerous pollutants.
Chakr Innovations, started by graduates from the Indian Institute of Technology, has capitalised on the smoke-belching machines that can be heard across the city.
Its Chakr Shield is fitted to generators and converts carbon and other fine particles, including the most harmful PM0.3 and PM2.5 specks, into liquified soot. The captured carbon is washed down with a solvent and processed into ink pigment and paints.
"What would have otherwise been a waste is captured and reborn to be used as a raw material again," said co-founder Arpit Dhupar, donning a t-shirt that says "black is the new green".

Source:AFP