The past week's air quality generally turned out to be better than that of previous weeks.

The only city with an air quality index averaging above 100, or slightly polluted, in the past week was Chongqing in southwest China.

But in the week before that, six cities -- Chongqing, Harbin, Jinan, Taiyuan, Lanzhou and Beijing -- were in that category.

No city was found to be heavily polluted. The index ranges between 300 and 500 for heavily polluted air.

Coastal cities in South China, including Haikou, Zhanjiang, Zhuhai, Xiamen, Beihai and Shantou, maintained a very good air quality index of under 50 in the past week, along with Nanning and Guilin in South China's Guangxi Zhuang Autonomous Region.

Hohhot, the capital city of North China's Inner Mongolia Autonomous Region, unexpectedly enjoyed very good air quality in the past week.

Beijing witnessed one day in the past week in which it had a very good air quality index of below 50, and six other days last week with rather good air quality index between 50 and 100.

This means that the entire week was ideal for Beijingers to get outdoors and take some exercise without risking their health.

Suspended particles were the major pollutants in most cities.

(China Daily May 22, 2004)