NBN EN 14791 : 2006

Foreword
1 Scope
2 Normative references
3 Terms, definitions, symbols and abbreviations
   3.1 Terms and definitions
   3.2 Symbols
   3.3 Abbreviations
4 Principle
   4.1 General
   4.2 Measuring principle
5 Reagents
   5.1 General
   5.2 Hydrogen peroxide
   5.3 Water
   5.4 Absorption solution, H[2]O[2]
   5.5 Reagents for chromatographic analysis
        5.5.1 Eluent solution
        5.5.2 Standard sulphate stock solution,
               10,4 x 10[-3] mol/l SO[2-][4]
        5.5.3 Regeneration solution for suppressor
   5.6 Reagent for Thorin analysis
        5.6.1 2-propanol
        5.6.2 Barium perchlorate, standard volumetric
               solution, = 0,005 mol/l
        5.6.3 Potassium hydroxide, standard volumetric
               solution, = 0,1 mol/l
        5.6.4 Perchloric acid, standard volumetric solution,
                = 0,1 mol/l
        5.6.5 Thorin, {4-[(2-arsonophenyl)-azo]-3-hydroxy-2,7
               naphthalene-disulfonic acid disodium salt} 2 g/l
               solution
6 Sampling equipment
   6.1 General
   6.2 Sampling probe
   6.3 Filter housing
   6.4 Particle filter
   6.5 Temperature controller
   6.6 Absorbers
        6.6.1 General
        6.6.2 Test of absorption efficiency
   6.7 Sampling pump
   6.8 Gas volume meter
7 Sampling procedure
   7.1 General requirements
   7.2 Preparation and installation of equipment
        7.2.1 Sampling location
        7.2.2 Sampling point(s)
        7.2.3 Assembling the equipment
        7.2.4 Heating of the sampling line
        7.2.5 Leak test
   7.3 Performing sampling
        7.3.1 Introduction of the probe in the duct
        7.3.2 Sampling
        7.3.3 Rinsing of the sampling system and
               preparation of the samples
   7.4 Measuring series
   7.5 Field blank
   7.6 Absorption efficiency
8 Analysis equipment
   8.1 Ion chromatograph
   8.2 Thorin method
        8.2.1 General
        8.2.2 Spectrophotometer (optional)
        8.2.3 Glass optical cuvette
9 Analytical procedure
   9.1 General
   9.2 Ion Chromatography method
        9.2.1 General procedure
        9.2.2 Interferences
        9.2.3 Calibration
   9.3 Thorin Method
        9.3.1 Pre-treatment of sample solution before
               analysis for Thorin method
        9.3.2 General procedure
        9.3.3 Preparation of a chemical blank solution
        9.3.4 Interferents
10 Determination of the characteristics of the method:
   sampling and analyse
   10.1 General
   10.2 Relevant performance characteristics of the method
        and performance criteria
        10.2.1 General
        10.2.2 Sampling procedure
        10.2.3 Analyse procedure
   10.3 Establishment of the uncertainty budget
11 Expression of results
12 Evaluation of the method in the field
13 Equivalence of Thorin and ion chromatography methods
   13.1 General
   13.2 Range
   13.3 Matrix effect
   13.4 Comparison of repeatability and trueness
14 Equivalence with an alternative method
15 Test report
Annex A (informative) Type of sampling equipment
Annex B (informative) Examples of absorbers
Annex C (informative) Example of assessment of compliance
         or reference method for SO[2] with requirements
         on emission measurements
Annex D (informative) Evaluation of the method
Annex E (informative) Test of equivalency of Thorin method
         and ion chromatography
Annex ZA (informative) Relationship with EU Directives
Bibliography

Explains a manual method for sampling and determining SO[2] content in ducts and stacks emitting to the atmosphere by two analytical methods: Ion chromatography and Thorin method.