In good news for backpackers planning to coincide a trip to China with a visit to the 2008 Olympic Games, environmental officials have managed to improve Beijing's air pollution problems.
The Beijing Environmental Protection Bureau (BEPB) took a million cars off the road this week, with air quality measured at Grade 2 on a one to five scale.
The subsequent worsening to Grade 3 once cars were permitted back on the roads showed that air pollution can be tackled.
Du Shaozhong, BEPB deputy chief, told Reuters: "The test has clearly demonstrated we are capable of providing good air quality for the Beijing Olympic Games.
"The accumulation of emissions clearly slowed over the four-day test. With these weather conditions, we would not have met air quality targets over four consecutive days without the restrictions."
He added: "If the air quality is as good as Grade 2, it would be suitable for activities including the (Olympic) sporting events."
