Hangzhou PM2.5 Chaohui Monitoring Point unveiled mystery for the first time yesterday
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In the past few days, reports on PM2.5 have been seen in various major media in Hangzhou, and the timetable for the release of PM2.5 monitoring data has been determined: March. So what exactly does the PM2.5 monitoring point responsible for collecting data look like?
Yesterday, Hangzhou PM2.5 Zhaohui monitoring site unveiled the media for the first time.
The total price of the monitoring point PM2.5 equipment is more than 10 million. "This is an automatic online device." At the Zhaohui monitoring point, Hongsheng Mao of the Hangzhou Environmental Monitoring Center stated that this set of equipment is expensive, and a radar system costs 2 million yuan. Chromatography Instrument 2 million yuan, 400,000 yuan particle size spectrometer ... ... Zhaohui monitoring point of a full set of equipment more than 10 million yuan.
In recent years, including the Zhaohui monitoring point, Hangzhou has already built seven PM2.5 monitoring stations in Wolong Bridge, Xiasha and Xiaoshan. At present, Hangzhou plans to build two monitoring sites at the Huajiachi Campus of Zhejiang University and the Yunxi Scenic Spot.
According to Hong Shengmao, Zhaohui's monitoring point was put into use only in May last year, but the equipment is the most complete and accurate compared to other monitoring points. The accuracy of the entire equipment monitoring has reached international standards.
In addition, Zhaohui's monitoring point is in the residential area, and the height of the instrument should be basically the same as the height of the surrounding residential floor, which is conducive to measuring the actual PM2.5 pollution in the residential area of ​​Hangzhou.
On the roofs of the 25 buildings, several tripods are standing, and the top of the rack is equipped with a PM2.5 data sampling pole.
"These devices are called particle sampling cutters. The sampling rods are coarse and fine. The coarse ones are used to collect PM2.5 particles. The fine tubes are used to collect PM2.5-PM10 particles. These particles are sampled and cut by the collector and the data will be displayed. In the substation's system platform," said Hong Shengmao.
The real-time concentration data of all the micro-particles collected by these sampling rods will be immediately transmitted back to the house's instruments and equipment, and then sent back to the Hangzhou Environmental Monitoring Center via Zhaohui Substation.
All PM2.5 air quality monitoring stations in Hangzhou are unguarded, and the Hangzhou Air Quality Inspection Center station regularly sends personnel to inspect.
At present, the Hangzhou PM2.5 data is relatively stable. In fact, the monitoring of PM2.5 data has been carried out in Hangzhou in the early years, but the data has not been released to the public.
The reporter through the official website of the Hangzhou Municipal Government, “Hangzhou, Chinaâ€, inquired about the implementation of the “Hangzhou Atmospheric Environment Improvement Seventh Stage (Special Regulation of Ashy Weather) Implementation Plan (2010-2012)†issued by the General Office of the Hangzhou Municipal Government in 2010.
According to this notice, “Particulates are still the primary pollutants in the atmospheric environment in Hangzhou, especially particulates in the particulates are heavily polluted. The average annual PM value in the urban area in 2006 was 77.46 ug. /m3, more than 4.2 times the annual average (15 ug/m3) regulated by the US Environmental Protection Agency (EPA)..."
Last night, the reporter asked Hong Shengmao, in the end the current PM2.5 data is higher or lower than the previous data? "Compared to 2006, the PM2.5 data monitored now should be relatively stable," explains Hong Shengmao.
The reporter learned from the second public consultation draft of the “Environmental Air Quality Standard†of the Ministry of Environmental Protection that the standard for the drafting of the standard limits, and taking into account the actual situation in China, set the PM2.5 according to one year and 24 hours respectively. The upper limit values ​​for the average concentration of 0.035 mg/m3 and 0.075 mg/m3 were determined.
"According to this national standard, the average concentration of PM2.5 contained in the air per cubic meter for 24 hours is 75 micrograms," an environmental professional told reporters.
Every 5 km/h reduction in the speed of a motor vehicle, the amount of sewage discharged is increased by 15%
On February 29, the executive meeting of the State Council was convened and agreed to issue the newly revised “Ambient Air Quality Standards.†The new standard added monitoring indicators for particulate matter (PM2.5) and ozone 8-hour concentration limits.
On the same day, the Air Pollution Control Conference was held in Hangzhou and the topic was also closely related to "PM2.5."
According to the research, there are two main sources of PM2.5 in Hangzhou: the first is the burning of coal, motor vehicles, dust, and fine particles emitted directly from the combustion of biomass, and the second is that the sulfur dioxide, nitrogen oxides, etc. in the gas are complicated. Secondary particles formed by chemical reaction.
According to the causes of the comparison with Hangzhou, it is found that the energy structure of Hangzhou's industrial structure is still not reasonable. For instance, in the one-time energy consumption structure, the proportion of coal has dropped from 77.7% in 2009 to 73.2% in 2010 and has remained high.
In addition, the pollution of motor vehicles in Hangzhou has shown a dramatic increase. In terms of total amount, the number of motor vehicles increased from 1,078,400 in 2005 to 2,074,600 in 2011, and urban congestion caused increased emissions. For every 5 km/h reduction in the speed of motor vehicles, the amount of pollutants increased by 15%. .
"The monitoring data in recent years shows that when the morning and evening peaks in Hangzhou are reached, the PM2.5 contained in the air is relatively high, and the air quality is showing a declining trend." Hong Shengmao said that during the day, the PM2.5 pollutants in the air of Hangzhou City are relatively small. At noon.
Learn how to understand PM2.5 against the national standard
Seeing the opening date of PM2.5 enters a countdown. It is best for everyone to learn how to read this data.
The sky in Hangzhou is often covered with layers of gray veil, which is the pollution of PM2.5 and other pollutants. PM2.5 can enter the lungs. Particles less than or equal to 2.5 microns in diameter, although 20 times smaller than a hair, but it is rich in a large number of toxic and harmful substances, can invade the human alveoli, into the human blood circulation , induced cardiovascular and other respiratory diseases.
"Compared with the national standard, if the PM2.5 per cubic meter of air exceeds 75 micrograms, it means that it has not reached the national standard. If it is less than 50 micrograms, it means that the target is met," explains Hong Shengmao.
If you can't read the data, the problem is not great. Before we go out, look at the sky is not gray, if gray, minimize outdoor activities, or really want to go out, it is recommended to wear a mask.