Are air purifiers really effective against Delhi’s pollution?

Also read: Pollution is for mad 'madams': How open fires are making Delhi a hell

Delhi is on fire at night. I live in south Delhi where many a home has guards stationed at the gates all night, and so do the city's colonies. Each one of these stations light open fires at night and keep them lit all night in the months of winter starting in November all the way to March.

This in a city where there is no wind or breeze during this time, and therefore the smoke simply keeps lingering in a white-grey haze. I took a drive through the city at night to find the exact situation out.

Every colony I went through, and also the police checkposts guarding the entry and exit points, had open fires made of wood, branches of seasonal trees that may be dry during this time, rubber tyres, thermocol packing material, plastic bags, and even cloth lit up. Seldom did I see the use of proper coal anywhere. Read more here.