The authorities plan to close factories and force 19 heavy polluters to reduce emissions by 30 percent for the two months around the Olympics and Paralympics, and measures to limit factory emission are also in place for areas surrounding the capital, including the city of Tianjin, the provinces of Hebei, Shanxi and Shandong, and the Inner Mongolia region.

Based on a study released last month by IOC's medical commission, Rogge said that the health of the athletes is "absolutely not in any danger" during Games time.

Officials are also confident about bringing traffic congestion under control with a ban on some cars during the Olympics and a plan to set up special lanes on key roads that link competition sites with the athletes' village, the media village and training venues.

"Private vehicles, excluding taxis, will be ordered to stay off roads every other day in accordance with the even and odd numbers on the licence plates," Beijing's vice mayor Ji Lin said last month.

"The government is working on a compensation scheme for car owners and we will announce it later," he added.

Highlighting the public's enthusiasm for the greatest show on Earth, more than one million people were in the hunt for an Olympics volunteer's post and training programs are well under way.

Third phase of the domestic ticket sales will start on May 5, with large crowds expected to chase the remaining 1.38 million tickets for 16 sports including volleyball, athletics, boxing and football.

Zhu Yan, director of the Olympic ticketing center, promised that there will be no repeat of the meltdown of the booking system that marred the previous round of sales.

"We have confidence in the system because our ticketing sponsor has increased the system's capacity by folds," he said. "Nonetheless, I hope that the public won't be hasty to buy tickets."

Demand is excessive outside the Chinese mainland, too. "The main pressure at the moment is that many National Olympic Committees continue to ask for more tickets," said Zhu. "We are trying to dig out resources for tickets to satisfy the demand worldwide."

Of the 6.8 million Olympic tickets available for sale, about 75 percent are reserved for the domestic public, with the rest going overseas.

The organizers are closer to selecting an official theme song with 30 candidate songs expected to be released at a gala show later on Wednesday.

"The final choice (of the theme song) is up to the BOCOG executive board," said Zhao Dongming, head of the BOCOG's cultural activities department.

Last, but not least, various campaigns aimed at improving the behavior of local citizens finally bore fruits. More and more people are getting to abandon old habits like spitting in public, jumping ahead in line and littering.

A survey released by Renmin University of China in February found that in 2007, 2.54 percent of people still spat, roughly a half of the figure for 2006, and the occurrence of littering in public dropped from 5.3 percent in 2006 to 2.86 percent in 2007 and queue-jumping from 6 percent to 1.5 percent.