Beijing started its most drastic pollution-control plan Sunday, restricting car use and limiting factory emissions in a last-minute push to clear smog-choked skies for the August Olympics.

Under the two-month plan, half of Beijing's 3.3 million cars will be removed from city streets on alternate days, depending on whether the license plate ends in an odd or even number.

Skies were relatively clear Sunday and traffic was light. But the real test will come when the work week begins.

To further ease traffic, employers have been asked to stagger work schedules and public institutions will open an hour later than normal.

Two new subway lines and an airport rail link should also bring relief to clogged roads. All three lines opened Saturday _ a month behind schedule.

"It's much faster than a taxi, so it's very good," said Ola Tunamder, who arrived Sunday from Helsinki, Finland, and took the airport train into the city.

Besides the traffic plan, chemical plants, power stations and foundries have to cut emissions by 30 percent beginning Sunday. Dust-spewing construction in the capital was to stop entirely.

While the government has said it hopes to reduce vehicle emissions, one of the city's chief sources of pollution, it is unclear how the effectiveness of the plan will be gauged. The government has not made public a specific target for emissions levels or said how it will measure air quality.

Despite striking venues and $40 billion spent on improving infrastructure, keeping the city's air clean for the world's greatest athletes participating in the Aug. 8-24 games has been China's greatest challenge. Continued...