Su, 28, a 1.6-liter emission Volkswagen Polo owner, had to leave her even-numbered car at home on the first day of the capital's four-day traffic and air test event.

Along with Su, most even-numbered vehicle-owners took bus and metro to work on Friday following the government's call to get 1.3 million cars off the road in order to improve air quality one year ahead of the Olympics.

By extending the rush hour from 2 to 3 hours and shortening the gap between train arrivals, more people took the metro and the passenger flow rose in an orderly manner.

Zhao Fang, a conductor at Xizhimen metro station on the city's loop line, said there was a 20 percent passenger rise starting 6:30 am, half an hour earlier than usual.

It is estimated that 200,000 to 300,000 more metro journeys were made, while there were 1.5 to 1.6 million more people took the bus.

Another 770 backup buses were put into operation to support the city's fleet of nearly 20,000 buses.

At 8:30 am, the monitoring screen in the city's traffic administration bureau showed improved traffic conditions compared with the same time on normal days.

"The speed used to be around 20 km per hour on the second and third ring roads around 8 am, but today looks much better," bureau official Shao Jie was quoted by Beijing Evening News as saying.

Road accidents also fell. However, full details will not be released until the four-day experiment ends, said the bureau.

Du Shaozhong, deputy director of the Beijing municipal environmental protection bureau, said a team of experts is keeping close watch on the data collected by all of its 32 monitoring stations.

He didn't reveal the data but said the impact was "obvious", adding that the capital achieved Grade II record on the first day of the test. Grade I and II are suitable for holding international events.

Wang Hongsheng, head of the Polo Car Club, told China Daily most of its 20,000 members supported the traffic restrictions, but only if it is a temporary policy.

"Four days is acceptable and we all know it's for the Olympics' sake. It's capital residents' responsibility to abide by the restriction," he said.

However, Liu Haitao, a veteran taxi driver, sees the trial as a signal to cool down people's growing demand for cars.

(China Daily August 18, 2007)