1、BRITISH STANDARDBS EN 14996:2006BS6068-5.42:2006Water quality Guidance on assuring the quality of biological and ecological assessments in the aquatic environmentThe European Standard EN 14996:2006 has the status of a British StandardICS 13.060.70g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g
2、3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58BS EN 14996:2006This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 June 2006 BSI 2006ISBN 0 580
3、 48757 1National forewordThis British Standard is the official English language version of EN 14996:2006.The UK participation in its preparation was entrusted by Technical Committee EH/3, Water quality, to Subcommittee EH/3/5, Biological methods, which has the responsibility to: A list of organizati
4、ons represented on this subcommittee can be obtained on request to its secretary.Cross-referencesThe British Standards which implement international or European publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Corresponde
5、nce Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online.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 does not of itse
6、lf confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep UK interests informed; monitor related international and European developments and promu
7、lgate them in the UK.Summary of pagesThis document comprises a front cover, an inside front cover, the EN title page, pages 2 to 14, an inside back cover and a back cover.The BSI copyright notice displayed in this document indicates when the document was last issued.Amendments issued since publicati
8、onAmd. No. Date CommentsEUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 14996June 2006ICS 13.060.70English VersionWater quality - Guidance on assuring the quality of biologicaland ecological assessments in the aquatic environmentQualit de leau - Guide dassurance qualit pour desvaluations biologiqu
9、es et cologiques danslenvironnement aquatiqueWasserbeschaffenheit - Anleitung zur Qualittssicherungbiologischer und kologischer Untersuchungsverfahren inder aquatischen UmweltThis European Standard was approved by CEN on 3 May 2006.CEN members are bound to comply with the CEN/CENELEC Internal Regula
10、tions which 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 Europe
11、an Standard 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
12、standards 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.EU
13、ROPEAN COMMITTEE 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 14996:2006: EEN 14996:2006 (E
14、) 2 Contents Page Foreword3 Introduction .4 1 Scope 5 2 Normative references 5 3 Terms and definitions .5 4 Principle8 5 Design of biological and ecological studies.8 6 Surveys and sampling.9 7 Analysis 9 8 Performance characteristics 11 9 Validation of results 11 10 Measurement uncertainty .12 11 I
15、nterpretation and reporting .12 12 Training.12 Bibliography 14 EN 14996:2006 (E) 3 Foreword This document (EN 14996:2006) 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 stan
16、dard, either by publication of an identical text or by endorsement, at the latest by December 2006, and conflicting national standards shall be withdrawn at the latest by December 2006. SAFETY PRECAUTIONS Safety issues are paramount when surveying surface waters. Surveyors should conform to EU and n
17、ational Health and Safety legislation and any additional guidelines appropriate for working in or near water. 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, Cz
18、ech 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. EN 14996:2006 (E) 4 Introduction The importance
19、 of ecology in new legislation such as the EC Water Framework Directive (WFD 2000/60/EC) means that ecological data from aquatic environments shall be of a known and verifiable quality. General guidelines on quality assurance are given in the EN ISO 9000 series and, especially, EN ISO/IEC 17025. Thi
20、s guidance standard is designed to complement these standards by providing advice specific to the quality assurance of ecological data collected from aquatic environments. The principles outlined in this standard are applicable to all field and laboratory work and to all organisations producing ecol
21、ogical data. According to the precise use to which this standard is to be put, it is essential for specifiers and users to agree on any necessary variations or optional procedural details prior to use. EN 14996:2006 (E) 5 1 Scope This guidance standard defines activities appropriate for ensuring tha
22、t the quality of ecological assessments in surface waters (including rivers, lakes, transitional and coastal waters and the open sea) and sediments meets specified requirements. This standard also covers hydromorphological aspects relevant to ecological assessment. While it has particular importance
23、 in relation to the assessment of ecological status in surface waters, it also applicable to other types of investigation and habitat. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applie
24、s. For undated references, the latest edition of the referenced document (including any amendments) applies. Not applicable. 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 accuracy closeness of agreement between the result of a measurement a
25、nd the true value of the measurand NOTE 1 Accuracy consists of bias (systematic error) and random error. NOTE 2 The true value is a value that would be obtained by a perfect measurement, thus true values cannot be determined and, consequently, accuracy is generally a hypothetical concept. In specifi
26、c cases a true value of a sample might be derived from interlaboratory studies as the mean value of all participants. This value should be regarded as a relative true value. For the purpose of this standard, accuracy can also refer to the application of the correct biological name to an organism. 3.
27、2 bias errors that are consistent rather than random in nature. Average of an infinite number of measurements of the same measurand under the same conditions divided by the true value of the measurand NOTE 1 As only a limited number of measurements can be performed bias can only be estimated. NOTE 2
28、 Often referred to as systematic error. 3.3 detection limit of discrete entities minimum number and/or size of a specific taxon or group of organisms in a sample at which its presence can be detected with a certain confidence 3.4 error difference between an individual result and the average (random
29、error) 3.5 fitness for purpose extent to which the performance of a protocol matches the criteria that best describes the end-users need NOTE Fitness should normally be assessed by a validation study. EN 14996:2006 (E) 6 3.6 metadata summary information about data covering: how they were created, co
30、mposition, limits of interpretation, quality of data, ownership and availability 3.7 measurand particular quantity subject to measurement NOTE In biological investigations, this refers to the number of organisms in a sample or percentage of covering of macrophytes. 3.8 performance characteristics ch
31、aracteristics of a specific method or protocol, which encompass qualitative and quantitative aspects of data such as detection limit, repeatability, reproducibility, precision, uncertainty, bias, method sensitivity, measurement range, interference and recovery 3.9 phenology study of changes in the m
32、orphology or physiology of organisms that occur over the course of a year in relation to internal or external stimuli (e.g. time of flowering in relation to climate) 3.10 precision closeness of agreement between independent results obtained under the same conditions NOTE Precision depends only on th
33、e distribution of random errors and does not relate to the true value or the specified value. 3.11 quality all the features and characteristics of a measurement result that bear on its ability to satisfy stated or implied needs 3.12 quality assurance all those planned and systematic actions necessar
34、y to provide adequate confidence that a product will satisfy given requirements of quality NOTE This includes AQC, audit, training, documentation of methods, calibration schedules, etc. 3.13 quality control operational techniques and activities that are used to fulfil requirements for quality 3.14 r
35、andom error difference between the result of a measurement and the average value obtained by an infinite series of measurements of the same measurand under the same conditions NOTE As only a limited number of measurements can be performed a random error can only be estimated. 3.15 recovery fraction
36、of a measurement component that is detected by the analysis NOTE This is often determined after addition of a known quantity of the measurement component. EN 14996:2006 (E) 7 3.16 reference collection collection of live or preserved specimens, whose identities have been confirmed independently, that
37、 is accessible to an analyst to aid in the identification and analysis of ecological samples NOTE A reference collection may also take the form of photographs or digital images. 3.17 repeatbility (of results of measurement) closeness of the agreement between the results of successive measurement of
38、the same measurand carried out under the same conditions of measurement 3.18 reproducibility (of results of measurement) closeness of the agreement between the results of measurement of the same measurand carried out under changed conditions of measurement. (observer, time, location, instruments etc
39、.) 3.19 statistical power ability of a statistical procedure to distinguish a situation different from the null hypothesis (H0: no difference, no effect or no change) NOTE In statistical terms: statistical power = (1-) in which is the probability of failing to reject H0when in fact H0is false. 3.20
40、taxon (pl. taxa) group of organisms related at a particular taxonomic level 3.21 taxonomic expert individual recognised by his/her peers as having particular taxonomic skills or knowledge 3.22 taxonomic level precision with which an organism is defined, for example family, genus or species 3.23 unce
41、rtainty parameter associated with the result of a measurement that characterises the dispersion of the values that could reasonably be attributed to the measurand NOTE Generally the parameter consists of a standard deviation. For most purposes an expanded uncertainty should be used obtained by multi
42、plying the combined standard uncertainty by a coverage factor (k). For an approximate level of confidence of 95 %, k is 2 (n 7, t-Statistics). The combined standard uncertainty is the result of a series of measurements in which the contribution of all relevant sources of uncertainty (both random and
43、 systematic) are combined. 3.24 validation (of a method) confirmation, through the provision of objective evidence, that the requirements for a specific intended use or application are fulfilled 3.25 verification confirmation of an identification, e.g. by a qualified person or an independent expert
44、EN 14996:2006 (E) 8 3.26 voucher specimen sample of one or more taxa taken from a specific location at a specific time that is preserved in order to permit independent verification of their identity 4 Principle The validity of biological and ecological investigations depends on the accuracy and prec
45、ision of all activities involved in the collection and analysis of data. Major variables include the characteristics of the taxonomic groups, the number of observations or measurements, their statistical distribution, the spatial or temporal representivity of samples, accuracy of identification guid
46、es, measuring devices or other methods, the skill of the surveyors or analysts in using these and the consistency of approach. This standard gives a general framework for ensuring the quality of biological and ecological investigations of aquatic environments. These procedures encompass study design
47、, surveying and sampling, analysis and identification, validation, data interpretation and reporting, and training of personnel. 5 Design of biological and ecological studies 5.1 General aspects Biological and ecological assessments of aquatic environments should start with a clear statement of the
48、qualitative and quantitative goals of the study. Methods chosen should be “fit for purpose” and should take account of their statistical power, in order to ensure that necessary spatial and temporal resolution is achievable and cost-effective. A written protocol for the method should be available. N
49、OTE 1 Wherever possible, the method used should be derived from an International or European Standard. Biological and ecological analyses of aquatic environments should be performed within the context of programmes that recognise the complexity of ecological systems, including temporal and spatial variability. Those aspects of temporal and spatial variation which should be incorporated in the sampling regime will be determined by the objectives of the study. Efforts should be made to minimise the impact of spatial and temporal variation if they are no subjects
