Polaris VOCs Online: Recently, Sichuan issued the 2019 Monitoring Plan for Volatile Organic Compounds in Urban Ambient Air of Sichuan Province. The full text is as follows:

2019 Monitoring Plan for Volatile Organic Compounds in Urban Air of Sichuan Province

Volatile organic compounds (VOCs) are important precursors of ozone pollution. In order to actively promote the monitoring system and capacity building of ambient air VOCs, find out the types of key VOCs that generate ozone, master the concentration level and change law of key VOCs, and support the prevention and control of ozone pollution, in accordance with the Monitoring Plan for Volatile Organic Compounds in Ambient Air of Cities at and above the Prefecture Level in 2019 (MH [2019] No. 11) issued by the Ministry of Ecology and Environment, This plan is formulated based on the actual situation of our province.

1、 Monitoring scope and items

In 2019, 21 cities (prefectures) in Sichuan Province will carry out the monitoring of non methane total hydrocarbons (NMHC) and VOCs in ambient air.

On the basis of the Monitoring Plan for Volatile Organic Compounds in Ambient Air of Key Areas in 2018 (HBMH [2017] No. 2024), Chengdu has increased the monitoring of non methane total hydrocarbon (NMHC) indicators since May.

The monitoring items in Meishan City and Zigong City include non methane total hydrocarbons (NMHC), 57 non methane hydrocarbons (PAMS substances) and 13 aldehyde ketone VOCs.

The remaining 18 cities (prefectures) are monitored for non methane total hydrocarbons (NMHC). 57 non methane hydrocarbons (PAMS substances) and 13 aldehydes and ketones VOCs should be carried out in places where the ultra-low emission dust meter is conditional or the ozone exceeds the standard. See Appendix 1 for monitoring items.

2、 Monitoring point

Each city shall set at least one monitoring point in the area with high ozone value in densely populated urban areas; In cities where conditions permit, monitoring points shall be added at upwind or background points, VOCs high concentration points, ozone high concentration points and regional impact edge monitoring points (downwind point).

See Attachment 2 for monitoring sites of volatile organic compounds in ambient air of the province.

3、 Monitoring method

Manual monitoring or automatic monitoring shall be adopted to encourage cities with conditions to carry out automatic monitoring. In order to ensure the comparability of monitoring data, it is recommended to give priority to the selection of automatic monitoring instruments that meet the relevant national standards for ecological environment protection and pass the applicability test of environmental monitoring instruments.

4、 Monitoring time and frequency

（1） Manual monitoring

The monitoring time and frequency of 21 cities (prefectures) in the province are as follows:

（2） Automatic monitoring

The automatic monitoring instruments for non methane hydrocarbon (NMHC) and VOCs components operate throughout the year and issue one group of monitoring data every hour. The automatic monitoring equipment of the ultra-low CEMS system is networked with the data business platform of China National Environmental Monitoring Center (hereinafter referred to as the Monitoring Center). It is recommended that the automatic monitoring points for VOCs components should be equipped with monitoring equipment for NO, NO2, O3, CO and meteorology.

5、 Monitoring methods

See Appendix 3 for the monitoring methods of non methane total hydrocarbon (NMHC) and VOCs components in the ambient air.

6、 Quality assurance and quality control

In order to ensure the accuracy of monitoring data, cross check, unified quality assurance and quality control measures, data audit and other means are used to conduct quality assurance and quality control management on sample collection, analysis and testing.

Manual monitoring: refer to the Technical Requirements for Manual Monitoring of Organic Substances in Ambient Air Ozone Precursors (Trial) (HBMH [2018] No. 240) (see Appendix 4 for details). In the process of sample collection and testing, carry out quality assurance and quality control in strict accordance with the requirements of standard methods, and fill in relevant original record forms; Review the validity of the data of the affiliated stations, and regularly organize cross inspections to check the surrounding conditions of the sampling points, the performance of the sampler (including the accuracy and stability of the sampling flow), the sample storage conditions, the operating procedures of the sampling personnel, the mass spectrum tuning report, the quality control records, etc. The cross inspection plan will be formulated and released separately. At the same time, the provincial general station analysis room will regularly check the implementation of quality control measures of each unit by means of spot check of quality control records, blind sample assessment, and comparison between laboratories.

Automatic monitoring part: carry out the operation and maintenance of automatic monitoring equipment in strict accordance with the operation instructions and operating procedures, use traceable standard samples for quality control, and ensure the accuracy and traceability of monitoring data. Automatic monitoring equipment shall ensure continuous online operation with Zui maximum limit, online rate not less than 80%, and data efficiency not less than 85%. The equipment shall not be shut down without reason during the period of major activity guarantee or heavy pollution (see Appendix 5 for specific quality control requirements for automatic monitoring).

7、 Data submission and transmission

Both manual and automatic monitoring results are passed through the data business platform of the monitoring terminal（ http://106.37.208.242:30005/cnemc/login.jsp ）Upload. The unit of data is unified as the volume concentration (nmol/mol) under the standard state (0 ℃, 1 standard atmospheric pressure), and the data are retained in two decimal places. Each city (prefecture) shall regularly submit the monitoring data report (see Appendix 6 for the format) and analysis report of the last month at all points in the administrative region to the provincial headquarters. The provincial master station will regularly report the timeliness and completeness of the monitoring results reported from all regions.

8、 Organization and implementation

From May 2019, all cities (prefectures) began to carry out VOCs monitoring.

Each city (prefecture) environmental monitoring station is responsible for the quality assurance and quality control of all local manual and online monitoring, and is responsible for the data networking of automatic monitoring equipment and monitoring master station within its administrative region, as well as the review and submission of manual and online monitoring data. Manual sampling of VOCs shall be conducted from 10:00 every day to 10:00 the next day (see Section IV "Monitoring Time and Frequency" for details); Complete the review of VOCs manual and automatic monitoring data of the previous month (automatic monitoring points include monitoring data such as NO, NO2, NOy, HONO, CO, O3, PANs, meteorological parameters, ultraviolet radiation intensity, photolysis rate, etc.) before the 2nd day of each month, and submit the reviewed manual monitoring data to the provincial master station analysis and test center; Before the 3rd day of each month, submit the data quality control report of the previous month to the provincial general station. The manual quality control report shall include the calibration curve, detection limit, continuous calibration, laboratory blank, transportation blank, parallel sample and other quality control results and standard gas certificate. The data related to the manual monitoring data shall be submitted to the provincial general station analysis and testing center, and the automatic monitoring data quality control report shall be submitted to the provincial general station atmosphere room.

The provincial master station analysis and test center and the atmospheric chamber respectively complete the quality control of manual and automatic monitoring of VOCs in each city (prefecture): the provincial master station analysis and test center and the atmospheric chamber respectively upload the final manual and automatic monitoring data to the national data business platform before the 5th day of each month of the VOCs online monitoring system; Before the 10th day of each month, the analysis and test center of the provincial general station shall complete the VOCs manual monitoring data quality control report of the previous month, and the atmospheric chamber of the provincial general station shall complete the data analysis report of the previous month and submit it to the China Environmental Monitoring General Station and Sichuan Provincial Department of Ecological Environment.