1、BRITISH STANDARDBS EN 1622:2006Water quality Determination of the threshold odour number (TON) and threshold flavour number (TFN)The European Standard EN 1622:2006 has the status of a British StandardICS 13.060.60g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g
2、44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58BS EN 1622:2006This British Standard was published under the authority of the Standards Policy and Strategy Committee on 29 September 2006 BSI 2006ISBN 0 580 48929 9National forewordThis
3、British Standard was published by BSI. It is the UK implementation of EN 1622:2006. It supersedes BS EN 1622:1998 which is withdrawn.The UK participation in its preparation was entrusted by Technical Committee EH/3, Water quality, to Subcommittee EH/3/2, Physical chemical and biochemical methods. A
4、list of organizations represented on EH/3/2 can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legal obli
5、gations.Amendments issued since publicationAmd. No. Date CommentsEUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 1622August 2006ICS 13.060.60 Supersedes EN 1622:1997 English VersionWater quality - Determination of the threshold odour number(TON) and threshold flavour number (TFN)Qualit de leau - D
6、termination du seuil dodeur (TON) etdu seuil de flaveur (TFN)Wasserbeschaffenheit - Bestimmung desGeruchsschwellenwerts (TON) und desGeschmacksschwellenwerts (TFN)This European Standard was approved by CEN on 14 July 2006.CEN members are bound to comply with the CEN/CENELEC Internal Regulations whic
7、h stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the Central Secretariat or to any CEN member.This European Standar
8、d exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the officialversions.CEN members are the national standards
9、bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania,Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COM
10、MITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2006 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 1622:2006: EEN 1622:2006 (E) 2 Contents
11、 Page Foreword4 Introduction .5 1 Scope 6 2 Normative references 6 3 Terms and definitions .6 4 Principle8 5 Hazards .8 6 Test environment.8 7 Apparatus and reagents8 8 Sampling and sample preservation .9 9 Test panel and selected assessors9 10 Procedure for unforced choice 10 10.1 General10 10.2 Ty
12、pe of test.10 10.2.1 The triangle test .10 10.2.2 The paired test .10 10.3 Type of method 10 10.3.1 Short method10 10.3.2 Full method.11 11 Expression of results 13 11.1 The short method.13 11.2 The full method 13 12 Test report 13 Annex A (normative) Chlorinated water 15 A.1 General15 A.2 Dechlorin
13、ation by addition of sodium thiosulfate15 A.2.1 Preparation of reagent 15 A.2.2 Procedure .15 A.3 Dechlorination by addition of ascorbic acid.15 A.3.1 Preparation of reagent 15 A.3.2 Procedure .15 Annex B (normative) Forced choice test method.16 B.1 General16 B.2 Determination of TON and TFN 16 B.3
14、Expression of results 17 B.3.1 The short method.17 B.3.2 The full method 17 B.3.3 Test report 17 Annex C (normative) Qualitative simplified procedure18 Annex D (informative) Method for the preparation of reference water).19 D.1 Apparatus and reagents19 D.2 Procedure .19 Annex E (informative) Selecti
15、on of the test panel20 EN 1622:2006 (E) 3 E.1 General .20 E.2 Self-evaluation .20 E.3 Screening test20 Annex F (informative) Preparation of dilutions23 Annex G (informative) Interlaboratory test by forced choice methodology .24 Bibliography27 Figures Figure G.1 Graphical presentation of threshold fl
16、avour number; calculated threshold flavour number is 13,5 .25 Tables Table 1 Threshold numbers13 Table E.1 Long term constraints form .21 Table E.2 Test report form for individual candidates.22 Table F.1 Examples of successive dilutions, xp(10.3. 2.2).23 Table G.1 Statistical evaluation by forced ch
17、oice triangle test (TFN), concerning the measurements obtained by 10 selected assessors, for assessment of drinking water (x=2).24 Table G.2 Measurements on odour and flavour on geosmin solutions (forced choice, triangle test)25 Table G.3 Measurements on odour and flavour on geosmin solutions (force
18、d choice, paired test)26 EN 1622:2006 (E) 4 Foreword This document (EN 1622:2006) has been prepared by Technical Committee CEN/TC 230 “Water analysis”, the secretariat of which is held by DIN. This European Standard shall be given the status of a national standard, either by publication of an identi
19、cal text or by endorsement, at the latest by February 2007, and conflicting national standards shall be withdrawn at the latest by February 2007. This document supersedes EN 1622:1997. The forced choice test method has been moved into Annex B. Annex C has been added. The standard has been completely
20、 editorially revised. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Irel
21、and, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EN 1622:2006 (E) 5 Introduction This European Standard gives quantitative methods for the determination of the threshold odour number (
22、TON) and the threshold flavour number (TFN). The main methodology (unforced choice) widely used in Europe is described in this European Standard. Another methodology, used by a limited number of member state (forced choice) is described in Annex B. A simplified qualitative method is also described i
23、n Annex C. The methods specified in this European Standard are based on the standard methods for sensory analysis. However, some differences are noted, as compared with those methods, due to water specificity. This European Standard is primarily intended to give a quantitative measure of odour and f
24、lavour of a water sample at a temperature of 23 C. NOTE The method can be used to determine the odour and flavour of a water sample at other temperatures but there will be no correlation between results obtained at different temperatures. WARNING Persons using this European Standard should be famili
25、ar with normal laboratory practice. This European Standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user to establish appropriate safety and health practices and to ensure compliance with any national regulatory conditio
26、ns. IMPORTANT It is absolutely essential that tests conducted according to this European Standard be carried out by suitably trained staff. EN 1622:2006 (E) 6 1 Scope This European Standard specifies quantitative methods for determining the TON and TFN of waters and also a qualitative method for det
27、ermining 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 th
28、reshold 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 flavou
29、r of drinking water and/or migration waters from materials in contact with waters. NOTE The 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 .) 2 Normative references The
30、 following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 7393-2, Water quality Determination of free chlo
31、rine and total chlorine Part 2: Colorimetric method using N,N-diethyl-1,4-phenylenediamine, for routine control purposes 3 Terms and definitions For the purposes of this European Standard, the following terms and definitions apply. 3.1 odour organoleptic attribute perceptible by the olfactory organ
32、on sniffing certain volatile substances (see ISO 5492) 3.2 flavour complex combination of the olfactory, gustatory and trigeminal sensations perceived during tasting. The flavour may be influenced by tactile, thermal, painful and/or kinaesthetic effects (see ISO 5492) 3.3 threshold odour number (TON
33、) dilution ratio beyond which the diluted sample does not have any perceptible odour ABATON+= (1) where EN 1622:2006 (E) 7 A is the volume of sample; B is the volume of reference water 3.4 threshold flavour number (TFN) dilution ratio beyond which the diluted sample does not have any perceptible fla
34、vour ABATFN+= (2) where A is the volume of sample; B is the volume of reference water 3.5 reference water water described as without any perceptible odour and flavour by test panel 3.6 test panel group of selected assessors used to evaluate flavour and odour NOTE For guidance on the selection of the
35、 test panel, see Annexes E or G. 3.7 selected assessor assessor chosen for his/her ability to perform a sensory test (see ISO 5492) 3.8 sample water intended for odour and flavour assessment 3.9 triangle test three test samples, two of which are reference water, and the third the sample or a dilutio
36、n of it, (or two of which are the sample or a dilution of it, and the third one is reference water), are presented to the selected assessors 3.10 paired test two test samples, one is the sample or a dilution of it, and the other is reference water are presented to the selected assessors 3.11 forced
37、choice even if the selected assessor is unable to perceive a difference between the two or three samples, the selected assessor shall chose one sample as having the stronger flavour or odour and record his/her choice 3.12 unforced choice selected assessor recording if he/she notes or does not note a
38、 difference between the two or three samples 3.13 migration water test water which has been in contact with a test piece under specified conditions EN 1622:2006 (E) 8 4 Principle The odour and flavour of a water sample are quantitatively assessed by a test panel by comparing that sample and/or dilut
39、ions of that sample with a reference water. The odour and flavour of a water sample may also be assessed qualitatively by only one selected assessor or a test panel to detect any abnormal odour and/or flavour. 5 Hazards Care shall be taken to ensure that the samples are safe for selected assessors.
40、If there is any suspicion of the presence of harmful microorganisms or of toxic substances at a toxic concentration, the samples shall not be tested without further precautions being taken. The selected assessors shall be instructed not to swallow any test sample. In case a toxicity risk is suspecte
41、d, samples should be evaluated for possible risks to the assessors by consideration of previous reports on toxicity tests, made with the sample or samples of similar kind, e.g. by using one of the existing standard methods for aquatic toxicity. In case the risk for presence of human pathogens (bacte
42、ria, viruses, parasite eggs) is suspected, it shall be assessed by adequate biological standard methods before conduction of this test. This is not necessary for waters disinfected by chlorinous disinfectants, ozone or UV. 6 Test environment The room used for odour and flavour assessment has to be f
43、ree from obtrusive draughts and noise and the general environment such that the selected assessors shall perform their task without being influenced by other selected assessors. No air fresheners or room deodorisers shall be used in the room. The room shall be sited away from any activity that could
44、 generate interfering odours. The temperature of the room shall be maintained with a system for the regulation of temperature at (23 2) C. It is advisable that this room is only used for odour and flavour assessment. Suggestions on the design of suitable facilities are given in ISO 8589. 7 Apparatus
45、 and reagents 7.1 Glassware, reserved solely for TON and TFN assessment. Glassware shall be cleaned separately from other laboratory items and, when not in use, shall be stored in clean conditions in order to avoid accidental contamination. Sample bottles, tasting glasses and volumetric glassware sh
46、all be cleaned before use so that they have no perceptible influence on the result of the assessment. Tasting glasses can be as specified by ISO 3591. NOTE Sample bottles should be of glass and of a suitable capacity. Stoppers should be of glass or polytetrafluoroethene (PTFE) and capable of yieldin
47、g no headspace in the sample. 7.2 Water bath or incubator, capable of maintaining a homogeneous temperature of (23 2) C. 7.3 Reference water Reference water (3.5) shall be used for rinsing, dilution and reference. EN 1622:2006 (E) 9 NOTE Reference water can be tap water, mineral bottled water, or pr
48、epared according to Annex D. Preferably it should be appropriate to the area and where possible similar in mineral character to the type of water being tested. 7.4 Cleaning liquids; use one of the following cleaning liquids for glassware. 7.4.1 Non-perfumed biodegradable laboratory detergent 7.4.2 H
49、ydrochloric acid, c(HCl) 2 mol/l. 7.4.3 Hydrogen peroxide, w(H2O2), approximately 3 %. NOTE Other cleaning liquids such as acetic acid can be used before the rinsing procedure of the glassware, provided they yield glassware free from interfering taste and odour. 8 Sampling and sample preservation Collect the samples (with no headspace) in the clean, well stoppered sample bottles (7.1). Keep the samples cool and in the absence of light during transportation and storage. If storage is necessary, store in a refrigerator at (4 2) C. Sto
