What are procedures for control of quality of automatic monitoring system in Vietnam?

What are procedures for control of quality of automatic monitoring system in Vietnam? - image from internet

Pursuant to Clause 2 Article 55 of the Circular 24/2017/TT-BTNMT on environmental monitoring techniques, which is promulgated by the Minister of Natural Resources and Environment, the procedures for control of quality of automatic monitoring system in Vietnam are stipulated as follows:

The quality of the system must be controlled before the system is officially put into operation and controlled once a year by a third party to ensure independence and objectivitiy. The following procedures shall be completed:

a) Test monitoring hole: regulation specified in Clause 2, Article 53 shall be complied with;

b) Test probe: regulation specified in subpoint d.1, Clause 1, Article 54 shall be complied with;

c) Check sample carrying duct: reference gas shall be used to check sample carrying duct as prescribed in subpoint d.2, Clause 1, Article 54. During the measurement of reference gases, entire pump system and monitoring equipment must still operate in the same mode as the measurement and analysis of exhaust gas flow. To be specific:

c.1) Measuring time for testing with reference gas is at least 20 minutes for every measurement;

c.2) In case the reference gas measurement data deviates by ≤ 5% from the reference gas concentration, the sample carrying duct meets the prescribed requirements. After the check, information shall be stored.

d) Check the pollution parameter monitoring equipment’s functions of measuring and convert the results into mg/Nm3.

dd) Check the gathering, storage and transfer of automatic continuous data of the system.

e) Check components and other functions of the system.

g) Evaluate the relative accuracy of the system, including:

g.1) Carry out reference monitoring

g.1.1) Reference monitoring is the use of periodic monitoring method specified in Section 7, Chapter II of this Circular or methods accepted by US EPA as the equivalent methods to refer and compare the achieved results and monitoring results of the system;

g.1.2) Reference monitoring of each parameter shall be carried out;

g.1.3) At least 06 samples shall be used for reference for every parameter to be monitored;

g.1.4) While the reference monitoring is being carried out, the facility’s capacity must reach at least 50% of the design capacity;

g.2) The reference monitoring data shall be evaluated using relative accuracy (RA). To be specific:

g.2.1) Reference monitoring data shall be calculated. Reference monitoring data of the system and reference monitoring method shall be used to calculate: difference, standard deviation, confidence coefficient and relative accuracy of each equipment and parameter according to the Appendix 10 enclosed herewith. The calculation result must be made into the record on checking of technical specifications, functions and RA of the system, which is specified in the Appendix 12 enclosed herewith;

g.2.2) In case RA is ≤ 20%, the monitoring data of the system is accepted for use;

g.2.3) In case RA is > 20%, the system operator must find causes and take remedial actions. After taking remedial actions, the reference monitoring must be carried out again to calculate RA until it satisfies the requirements specified in point g.2.2 of this Article, then the monitoring data of the system is accepted for use.

h) QC information shall be made into the record on checking of technical specifications, functions and RA of the system, which is specified in the Appendix 12 enclosed herewith.

Best regards!