The many masked faces of Beijing

For many locals in Beijing this week, the face mask is the one item you don't leave home without. Photo / AP

As Beijing continues to suffer through its red alert pollution emergency, New Delhi is planning to bring in measures to cut down on pollution.

On January 1, residents of New Delhi will only be able to drive in the city every other day depending on whether their licence plate bears an even or odd number.

The Delhi Government announced the measure in an effort to combat rising pollution levels in the Indian capital, considered among the worst in the world.

Unhealthy smog hovered over downtown Beijing yesterday as limits on cars, factories and construction sites kept pollution from spiking even higher, on the second of three days of restrictions triggered by the city's first red alert for smog.

Cars with even-numbered licence plates were kept off roads, and schools and constructions sites remained closed. Far fewer than usual pedestrians walked the streets - many of them wearing white masks to filter the air. A New York Times report from Beijing said that walking through the city was like "strolling through a coal mine".

A grey soupy haze subsumed Beijing's unique landmarks, convenience stores sold air-filtering masks at brisk rates and healthfood stores promoted pear juice as a traditional Chinese tonic for the lungs.

"And air purifiers at home are a must," Beijing resident Sun Yuanyuan said at a downtown Beijing juice shop.

No car days

Cities around the world that have implemented clean-air driving restrictions:

• Mexico City: In 1989 banned cars one day a week depending on the last number of the licence plate.

• Bogota, Colombia: Banned cars two days a week in peak traffic hours.

• Beijing: Banned cars one day a week based on licence plate numbers during the 2008 Olympics.

• Stockholm: LEZ (low-emission zone) programme implemented in 1996 banned cars from designated areas if they fall below emissions standards.

• London: Implemented congestion charge in central city in 2003 and five years later introduced an LEZ programme.

• Berlin: Began an LEZ programme that banned all diesel vehicles without a closed-loop catalytic converter in 2008.

• Paris: Banned all cars - except buses, taxis and emergency vehicles - from driving around landmarks between 9am and 4pm.

- Bloomberg - AP