and lúwān shī zhuān fùxiǎo (上海师范专科学校附属小学).
The first station is maintained by US Consulate in Shanghai, while the two last ones are provided by Shanghai Environment Monitoring Center(上海市环境监测中心), which is governmental center.
If you have concerns about some stations reporting lower PM2.5 data compared to others, then refer to the following graphics; they show the relative PM2.5 reporting for the last 5 days for each of the above mentioned stations:
Shanghai AQI data is now based on the maximum PM2.5 AQI data for 3 stations: Shanghai US Consulate (上海美国总领事馆), Jing'an Monitoring Station (静安监测站)
and lúwān shī zhuān fùxiǎo (上海师范专科学校附属小学).
The first station is maintained by US Consulate in Shanghai, while the two last ones are provided by Shanghai Environment Monitoring Center(上海市环境监测中心), which is governmental center.
If you have concerns about some stations reporting lower PM2.5 data compared to others, then refer to the following graphics; they show the relative PM2.5 reporting for the last 5 days for each of the above mentioned stations:
| Shanghai US Consulate (上海美国总领事馆) PM2.5 AQI reported by Shanghai US consulate |  |
| lúwān shī zhuān fùxiǎo (上海师范专科学校附属小学) PM2.5 AQI reported by Shanghai MEP |  |
| Jing'an Monitoring Station (静安监测站) PM2.5 AQI reported by Shanghai MEP |  |
As you can see, the reality is that Shanghai Environmental Protection Center and Shanghai US Consulate PM2.5 data is similar. And actually, in many case, the raw µg/m3 PM2.5 data reported by China MEP (China Ministry of Environmental Protection, to which Shanghai EP Center is reporting data) is actually higher than what is reported by the US consulate.
Some of the readers might be surprised since other apps (like the famous Dirty Beijing) are known to "highlight" lower AQI measured by MEP compared to the US data. The reason is that they do not use the same PM2.5 µg/m3 to AQI convertion for MEP and US data, meaning that they are comparing apple and bananas.
In this web site, all pollutant data (PM2.5, PM10, NO2, SO2, CO, O3) are converted from µg/m3 to AQI using the same convertion formula, which is the official EPA (US Environment Protection Agency) (revision from 2011, which is much more stict than the 2006 one; sorry no we cannot find the link to this revision). Only usign this unique convertion formula, it makes sense to compare the AQI data.
So, now, you might ask what is the trick with the MEP data? Well, it is just that the US EPA convertion formula is much more strict than others (and even more for the 2011 one), especially for AQI values below 150. So, if you look at the raw PM2.5 µg/m3 data, values are very much similar between US and MEP. But if you look at the AQI converted values , then, yes, China MEP based convertion formula AQI values are lower than the US EPA based convertion formula AQI values. But no worry, this site only uses the US EPA convertion formula, so regarless of which center is reporting the PM2.5 µg/m3 data, you will always get the safe AQI measurement based on the US Environment Protection Agency.
(中文版请点击此处 )
