Air quality gets better test

Shanghai, 24 other cities adopt new system for checking area pollution

Shanghai and all prefecture-level cities in Jiangsu and Zhejiang provinces will today begin using a new air quality reporting system.

The Shanghai Environmental Protection Bureau said the new system will provide more authentic readings of the city's air quality to the public.

As of Friday, the cities will upgrade from the Air Pollution Index to the Air Quality Index.

Fu Qingyan, chief engineer at the Shanghai Environmental Monitoring Center, explained the difference.

She said the Air Pollution Index only monitored sulfur dioxide, nitrogen dioxide and PM10 - particulate matter 10 microns or less in diameter - and calculated air quality indices for these pollutants.

"The new evaluation criteria takes the results of PM2.5 (particulate matter 2.5 microns or less in diameter), carbon monoxide and ozone into consideration in addition to figures for sulfur dioxide, nitrogen dioxide and PM10," she said.

Fu also said assessment results would be announced more often. "They will be updated once an hour, while the old system only gave results once a day," she said.

"We'll offer more comprehensive assessment results as we've got a more stable system and more monitoring stations to collect data," Fu said.

In June, Shanghai became the first city in China to post readings for PM2.5 from 10 monitoring stations scattered across the city. But air quality assessments by the Shanghai authorities and by the United States Consulate General in the city showed a discrepancy because they used different standards, environmental officials said.

Qian Hua, director of the research institute of atmospheric environment under the Shanghai Academy of Environmental Sciences, said the difference in readings stemmed from the evaluation standards adopted by the two countries, which are at different stages of economic development and environmental protection.

The US consulate said its readings indicate air quality in the area surrounding its downtown offices, and are published to make health data available to the US community in the municipality. However, the 10 monitoring stations set up by the Shanghai Environmental Monitoring Center are in different districts, ranging from downtown areas to suburbs.

Zhang Xiangzhi, from the Jiangsu Environmental Monitoring Center, said the fact that 13 cities in Jiangsu, 11 in Zhejiang, and Shanghai had decided to update their system on the same day can better control air pollution in the Yangtze River Delta.

"The problem of air quality is regional, and to gather assessment results in a relatively bigger area is believed to be useful in terms of joint prevention of air pollution," she said.

She said the new system, giving air quality readings from 13 cities in the province, means she will be able to see changes over a 24-hour period once she logs into the system.

Zhang said she is not worried about potential complaints from people living in Jiangsu who might find they have a worse air quality reading after the update. "The whole purpose of updating the reporting systems is to give the public a more comprehensive and concrete statement (of air quality)," she said.

Shanghai authorities say an app for mobile phones on the Air Quality Index will be available.

Chengdu, capital of Southwest China's Sichuan province, said last weekend it will update its air monitoring system from the Air Pollution Index to the Air Quality Index from next year.

shiyingying@chinadaily.com.cn