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Beijing 2008: Frequently Asked Questions


The quality of air in cities in PRC can be assessed in two ways: through analysis of the trends of ambient concentration levels or of air pollution index (API). Although the first method is preferable, actual data on ambient air quality may not always be readily available.

Ambient air quality monitoring is conducted at various administrative levels: national, province, city, and county levels.

China has a special air quality monitoring network of 113 key cities. Until 2005, there are 226 national air quality monitoring stations and 793 monitoring sites in all. The number of monitoring sites in urban areas is determined by the population number.

In addition to ambient air quality monitoring, environmental monitoring activities related to air pollution in the PRC also include acid rain monitoring, and sandstorm monitoring to track status of common pollutants, acid rain precursors (SO2, NO2), and dust.


1. CAI-Asia, Country Synthesis Report on Urban Air Quality Management, People’s Republic of China, December 2006
2. Current condition of environment monitoring facilities in China.


The air pollution index (API) is derived from measured pollutant concentrations. It integrates information on pollutant concentrations across an entire monitoring network into a single number that represents the worst daily air quality experienced in an urban area/city.

The API is calculated using this formula:


Ii is the API of certain montoring site, i.

Ci stands for the ambient air quality concentration of site i.

Ci,j indicates ambient air quality concentration data at the turning point that is just smaller than Ci.

Ci,j+1 is the air quality concentration data at the turning point that is just larger than Ci.

In terms of the current characteristics and prevention of air pollution in China, the calculation of API covers three pollutants: SO2, NO2, PM10 , whose gradation are as follows.

Daily mean concentration of contamination (mg/m3)

50 0.05 0.08 0.5
100 0.15 0.12 0.15
200 0.8 0.28 0.35
300 1.6 0.565 0.42
400 2.1 0.75 0.5
500 2.62 0.94 0.6

The calculation of the ambient air concentration data can be divided into two stages: first, the determination of the daily average concentration data of a monitoring site as indicated the average concentration data of a certain site; second, the calculation of the average concentration data of the whole city (based on the monitoring result of separate monitoring sites).

The standards above are based on 24-hr averages. Today’s API is the 24-hr average from 12 p.m. yesterday to 11 a.m. today. Today’s API must be reported to the Ministry of Environment Protection (MEPA) of China before 1 pm every day. At the same time, it is also faxed to the media.



The air quality monitoring sites in Beijing can be classified into: national control site, city control site, transportation site, background site and transfer site. In all, there are 27 monitoring sites in Beijing: Dongsi, Guanyuan, Tiantan, Wan Shou Xi Gong, Olympic Main Stadium, Nong Zhan Guan, Zhi Wu Yuan, Haidian North New Region, Wan Liu, Yun Gang, Feng Tai Garden, Gu Cheng, Yizhuang Developing Region, Long Quan Township, Liang Xiang, Tong Zhou Township, Ren He Township, Ding Ling, Chang Ping Township, Huang Cun Township, Yu Fa, Huai Rou, Ping Gu, Miyun Reservior, Miyun Townshiop, Yanqing Township, BaDaLing. Ding Ling site is the clean background site.

Chinese Source:

There are 13 monitoring sites in Tianjin including the Monitoring Center: ,
Relay Factory, Nanjing Road, Vehicle factory, Hedong Road, Tianshan Road, Hexi Road, Meijiang Community, Yong Ming Road, Taifeng Industrial Park, Dong Li Middle School, Bei Chen Region Scientific Park, Tuan Po Wa. Tuan Po Wa is the site in Tianjin which has the cleanest air quality.

Chinese Source:

There are 23 monitoring sites in Shanghai located in 19 regions.

Source: Duan Yusen et al. Studies on the Optimization of TSP-Pb Monitoring Sites in Shanghai. Environmental Science and Management. Sep. 2007. Vo. 32 No. 9

There are 13 monitoring sites in Qingdao, reporting daily air quality of 7 regions.

Chinese Source:

There are 11 monitoring sites in Shenyang, including Er Mao, Taiyuan Road, Wen Yi Road, Xiao He Yan, Bei Ling, Pao Xiao, Zhang Shi, Dong Qin, Hun Nan Er, Liaoning University, Hui Shan. Hui Shan is the clean background site.

Chinese Source:

There are 5 monitoring sites in Qinhuangdao, including the Monitoring Center: Beidaihe River EPB, Qin Yuan, Di Yi Guan and Jianshe Building.

Chinese Source:

Hong Kong
There are 14 fixed monitoring sites in Hong Kong, including Tung Chung, Yuen Long, Tsuen Wan, Tai Po, Sha Tin, Kwai Chung, Sham Shui Po, Mong Kok, Central/Western, Central, Causeway Bay, Eastern, Kwun Tong.

Source: Environmental Protection Department, Government of Hong Kong SAR (


It was regulated that all the monitoring sites in the urban areas of those 7 cities should adopt automated monitoring technologies. In accordance with the Automated Methods for Ambient Air Quality Monitoring of HJ/T193-2005, sampling and analyzing methods for each pollutant have been put in place, such as the Chemical Luminous Method and DOAS method for NO2, ultra violet fluorescence and DOAA methods for SO2 and O3.

Source: (SEPA. Automated Methods for Ambient Air Quality Monitoring of HJ/T193-2005. 2005, pg 17)


To fulfill Green Olympics promise, the Ministry of Environmental Protection of the People's Republic of China and Beijing Municipal Government jointly developed a strategy called "air quality protection measures for the 29th Olympic Games," involving six provinces in northern China- Beijing Municipal, Hebei Province, Tianjin City, Shanxi Province, Inner Mongolia Municipality, Shandong. The special monitoring scheme included 2 new key aspects, including increasing air quality monitoring stations, and air quality forecast, report and management under extreme environment atmospheric conditions.

During the Olympics, 6 mainland Olympic cities will increase their air quality monitoring stations. The monitoring period scales from June 1st to September 30th, 2008, with 27 regular monitoring stations and 17 temporary monitoring stations in the Olympics stadiums. The monitoring will be organized by several research institutions including CAS, Peking University, adopting many advanced technological approaches, like tower monitoring, aerial monitoring, laser and satellite remote sensing monitoring etc, as an integrated multi-dimensional monitoring on regional air pollution (covering 12 key sites in Tianjin, Hebei)

The Olympic monitoring scheme strengthens the reporting and response to environment pollution problems, particularly during extreme atmospheric conditions.

Source: Olympic Air Quality Monitoring, Forecasting and Assessment Plan, 2008, approved by national council


As with Beijing, cities where previous Olympics were held were also plagued with concerns surrounding air quality. This may be because most of the Olympics are held in large cities where smog is often a problem. This is especially true for cities such as Los Angeles in 1984, Seoul in 1988 and Athens in 2004. Visit the Key Reports to view a collection of articles, reports and data on air quality situation and measures taken during previous Olympics.

Beijing 2008


AQ Actions by Olympic Cities
- Overview of Actions
- Beijing
- Hong Kong
- Qinhuangdao
- Qingdao
- Shanghai
- Shenyang
- Tianjin
Air Quality in Olympic Cities
- Annual Pollutant Concentration
- Air Pollution Index (API)
- Calculated PM10 Analysis
- Olympic AQ Charts and Datasets
Other links
Key Reports
Key Resources

Air Quality in Chinese Cities
Courtesy of VECC-SEPA

API to Concentration ConverterAPI to Concentration Converter
[.xls, 29.1Kb]

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