EN 14791:2017

European foreword
1 Scope
2 Normative references
3 Terms and definitions
4 Symbols and abbreviations
5 Principle
6 Description of measuring system
7 Performance characteristics of the SRM
8 Field operation
9 Analytical procedure
10 Expression of results
11 Equivalence of Thorin and ion chromatography methods
12 Equivalence of an alternative method
13 Measurement report
Annex A (informative) - Validation of the method in the field
Annex B (informative) - Examples of absorbers
Annex C (informative) - Example of assessment of compliance of
        standard reference method for SO[2] with requirements on
        emission measurements
Annex D (informative) - Type of sampling equipment
Annex E (informative) - Example of comparison of repeatability and
        trueness of Thorin Method and Ion Chromatography Method
Annex F (informative) - Calculation of the uncertainty associated
        with a concentration expressed on dry gas and at an oxygen
        reference concentration
Annex G (informative) - Significant technical changes
Bibliography

This European Standard specifies the standard reference method (SRM) for the determination of the sulphuric oxide SO2 in flue gases emitted to the atmosphere from ducts and stacks. It is based on a sampling system and two analytical principles: ion chromatography and the Thorin method. This European Standard specifies the performance characteristics to be determined and the performance criteria to be fulfilled by measuring systems based on the measurement method. It applies to periodic monitoring and to the calibration or control of automatic measuring systems (AMS) permanently installed on a stack, for regulatory or other purposes. This European Standard specifies criteria for demonstration of equivalence of an alternative method to the SRM by application of prEN 14793.This European Standard has been evaluated during field tests on waste incineration, co-incineration and large combustion installations. It has been validated for sampling periods of 30 min in the range of 0,5 mg/m³ to 2 000 mg/m³ of SO2 for an ion-chromatography variant and 5 mg/m³ to 2 000 mg/m³ of SO2 for the Thorin method according to emission limit values laid down in the Directive 2010/75/EC.The limit values of EU Directives are expressed in units of mg/m³ of SO2 on dry basis and at standard conditions of 273 K and 101,3 kPa.NOTEThe characteristics of installations, the conditions during field tests and the values of repeatability and reproducibility in the field are given in Annex E.