EN 1622:2006

Foreword
Introduction
1 Scope
2 Normative references
3 Terms and definitions
4 Principle
5 Hazards
6 Test environment
7 Apparatus and reagents
8 Sampling and sample preservation
9 Test panel and selected assessors
10 Procedure for unforced choice
   10.1 General
   10.2 Type of test
        10.2.1 The triangle test
        10.2.2 The paired test
   10.3 Type of method
        10.3.1 Short method
        10.3.2 Full method
11 Expression of results
   11.1 The short method
   11.2 The full method
12 Test report
Annex A (normative) Chlorinated water
      A.1 General
      A.2 Dechlorination by addition of sodium thiosulfate
          A.2.1 Preparation of reagent
          A.2.2 Procedure
      A.3 Dechlorination by addition of ascorbic acid
          A.3.1 Preparation of reagent
          A.3.2 Procedure
Annex B (informative) Forced choice test method
      B.1 General
      B.2 Determination of TON and TFN
      B.3 Expression of results
          B.3.1 The short method
          B.3.2 The full method
          B.3.3 Test report
Annex C (informative) Qualitative simplified procedure
Annex D (informative) Method for the preparation
        of reference water
      D.1 Apparatus and reagents
      D.2 Procedure
Annex E (informative) Selection of the test panel
      E.1 General
      E.2 Self-evaluation
      E.3 Screening test
Annex F (informative) Preparation of dilutions
Annex G (informative) Interlaboratory test by forced
        choice methodology
Bibliography

This European Standard specifies quantitative methods for determining the TON and TFN of waters and also a qualitative method for determining any abnormal odour and/or flavour. It is essential that the safety remarks in Clause 5 are taken into account.Two quantitative methods are described:a short method applicable when either a sample has no odour and flavour or when the odour and flavour are to be compared with a specified threshold number;a full method applicable when the threshold number for the sample is to be determined.For both quantitative methods, two different methodologies are described:unforced choice in the standard;forced choice in Annex B.Both methods are applicable for quantifying the odour and flavour of drinking water and/or migration waters from materials in contact with waters.NOTEThe choice of the quantitative or qualitative method is depending on the national regulations, and on the type of water to be assessed (raw water, distribution water, migration water ….)