The PM2.5 monitoring station at Dongsiliutiao, Dongcheng district is one of the 35 monitoring locations connected to the Beijing Municipal Environmental Monitoring Center.
The equipment is fitted with 3G data transmission to send the reading to the monitoring center.
Air from the roof enters a pipeline to the monitoring equipment and via the 3G network the data is sent back to the Beijing Municipal Environmental Monitoring Center.
Mr Yang is an engineer from the center, who is regularly fine-tuning the equipment and replacing parts.
As of October 6, the second batch of fifteen PM2.5 monitoring sites went live and can be checked at Beijing Municipal Environmental Monitoring Center website. The data from the 35 monitoring sites in the capital can be viewed on the website.
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Video: Yu Chenkang
Voiceover: Brian Salter
Producer: Flora Yue