EN ISO 17994:2014
(Main)Water quality - Requirements for the comparison of the relative recovery of microorganisms by two quantitative methods (ISO 17994:2014)
Water quality - Requirements for the comparison of the relative recovery of microorganisms by two quantitative methods (ISO 17994:2014)
ISO 17994:2014 specifies an evaluation procedure for comparing two methods with established performance characteristics according to ISO/TR 13843 and intended for the quantification of the same target group or species of microorganisms.
It provides the mathematical basis for the evaluation of the average relative performance of two quantitative methods against chosen criteria for the comparison. It does not provide data for assessment of the precision of the methods being compared. It is appropriate that the precision of methods is assessed as part of their performance characterization.
ISO 17994:2014 does not provide methods for the verification of method performance characterization in a single laboratory.
Wasserbeschaffenheit - Anforderungen für den Vergleich der relativen Wiederfindung von Mikroorganismen durch zwei quantitative Verfahren (ISO 17994:2014)
Diese Internationale Norm legt ein Bewertungsverfahren fest, um zwei Verfahren mit etablierten Leistungsmerkmalen nach ISO/TR 13843 zu vergleichen, die für den Nachweis oder die Quantifizierung derselben Zielgruppe oder Spezies von Mikroorganismen vorgesehen sind.
Diese Internationale Norm liefert die mathematische Grundlage für die Bewertung der durchschnittlichen relativen Leistungsfähigkeit von zwei Verfahren unter Heranziehung festgelegter Gleichwertigkeitskriterien. Sie liefert keine Daten, die eine Bewertung der Präzision der verglichenen Verfahren erlaubt. Es ist zweckmäßig, dass die Genauigkeit der Verfahren im Rahmen ihrer Leistungscharakterisierung beurteilt.
Diese Internationale Norm enthält keine Methoden, um die Leistungsfähigkeit eines Verfahrens in einem einzelnen Labor zu verifizieren.
Qualité de l'eau - Exigences pour la comparaison du rendement relatif des microorganismes par deux méthodes quantitatives (ISO 17994:2014)
L'ISO 17994:2014 spécifie une procédure d'évaluation qui permet de comparer deux méthodes avec des caractéristiques de performance établies conformément à l'ISO/TR 13843 et visant à quantifier le même groupe cible ou la même espèce de micro-organismes.
Elle fournit les bases mathématiques pour évaluer les performances relatives moyennes des deux méthodes quantitatives par rapport à des critères de comparaison déterminés. Elle ne fournit aucune donnée permettant d'évaluer la fidélité des méthodes comparées. Il convient que la fidélité des méthodes soit évaluée lors de la détermination de leurs caractéristiques de performance.
L'ISO 17994:2014 ne propose aucune méthode permettant de vérifier les caractéristiques de performance des méthodes au sein d'un seul laboratoire.
Kakovost vode - Zahteve za primerjavo relativne ponovitve mikroorganizmov z dvema kvantitativnima metodama (ISO 17994:2014)
Standard EN ISO 17994 določa postopek ocenjevanja za primerjavo dveh metod kvantifikacije iste ciljne skupine ali vrste mikroorganizmov. Ta mednarodni standard zagotavlja matematično osnovo za ocenjevanje povprečne relativne učinkovitosti dveh kvantitativnih metod glede na izbrane kriterije primerjave. Ne zagotavlja podatkov, ki bi omogočili ocenjevanje natančnosti primerjanih metod. Natančnost metod naj bi se ocenjevala kot del njihove validacije. Ta mednarodni standard ne zagotavlja metod za preverjanje učinkovitosti metod v enem laboratoriju.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
01-september-2014
1DGRPHãþD
SIST EN ISO 17994:2004
Kakovost vode - Zahteve za primerjavo relativne ponovitve mikroorganizmov z
dvema kvantitativnima metodama (ISO 17994:2014)
Water quality - Requirements for the comparison of the relative recovery of
microorganisms by two quantitative methods (ISO 17994:2014)
Wasserbeschaffenheit - Anforderungen für den Vergleich der relativen Wiederfindung
von Mikroorganismen durch zwei quantitative Verfahren (ISO 17994:2014)
Qualité de l'eau - Exigences pour la comparaison du rendement relatif des
microorganismes par deux méthodes quantitatives (ISO 17994:2014)
Ta slovenski standard je istoveten z: EN ISO 17994:2014
ICS:
07.100.20 Mikrobiologija vode Microbiology of water
13.060.70 Preiskava bioloških lastnosti Examination of biological
vode properties of water
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
EUROPEAN STANDARD
EN ISO 17994
NORME EUROPÉENNE
EUROPÄISCHE NORM
February 2014
ICS 07.100.20; 13.060.70 Supersedes EN ISO 17994:2004
English Version
Water quality - Requirements for the comparison of the relative
recovery of microorganisms by two quantitative methods (ISO
17994:2014)
Qualité de l'eau - Exigences pour la comparaison du Wasserbeschaffenheit - Anforderungen für den Vergleich
rendement relatif des microorganismes par deux méthodes der relativen Wiederfindung von Mikroorganismen durch
quantitatives (ISO 17994:2014) zwei quantitative Verfahren (ISO 17994:2014)
This European Standard was approved by CEN on 8 February 2014.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same
status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United
Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2014 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 17994:2014 E
worldwide for CEN national Members.
Contents Page
Foreword .3
Foreword
This document (EN ISO 17994:2014) has been prepared by Technical Committee ISO/TC 147 "Water quality"
in collaboration with 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 identical
text or by endorsement, at the latest by August 2014, and conflicting national standards shall be withdrawn at
the latest by August 2014.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 17994:2004.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech
Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece,
Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.
Endorsement notice
The text of ISO 17994:2014 has been approved by CEN as EN ISO 17994:2014 without any modification.
INTERNATIONAL ISO
STANDARD 17994
Second edition
2014-02-15
Water quality — Requirements for the
comparison of the relative recovery of
microorganisms by two quantitative
methods
Qualité de l’eau — Exigences pour la comparaison du rendement
relatif des microorganismes par deux méthodes quantitatives
Reference number
ISO 17994:2014(E)
©
ISO 2014
ISO 17994:2014(E)
© ISO 2014
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form
or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior
written permission. Permission can be requested from either ISO at the address below or ISO’s member body in the country of
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ii © ISO 2014 – All rights reserved
ISO 17994:2014(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms, definitions and symbols . 1
3.1 Terms and definitions . 1
3.2 Symbols and abbreviated terms. 3
4 Principle . 3
5 Basic requirements for a comparison study . 4
5.1 General . 4
5.2 Description of methods . 4
5.3 Types of samples . 4
5.4 Number of samples and participating laboratories . 5
5.5 Counting and confirming. 7
6 Calculations. 8
6.1 Preliminary editing of the raw data . 8
6.2 Basic relative differences . 8
6.3 Half-width of the confidence interval . 9
7 Evaluation . 9
7.1 Preliminary evaluations . 9
7.2 Two-sided evaluation .10
7.3 One-sided evaluation .12
8 Test report .13
Annex A (informative) Flowchart .14
Annex B (informative) Comparison studies .15
Annex C (informative) Derivation of equation for calculation of the number of samples .17
Annex D (informative) Example of a two-sided evaluation
........................................................................................................19
Bibliography .22
ISO 17994:2014(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2, www.iso.org/directives.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any
patent rights identified during the development of the document will be in the Introduction and/or on
the ISO list of patent declarations received, www.iso.org/patents.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the meaning of ISO specific terms and expressions related to conformity
assessment, as well as information about ISO’s adherence to the WTO principles in the Technical Barriers
to Trade (TBT) see the following URL: Foreword - Supplementary information
The committee responsible for this document is ISO/TC 147, Water quality, Subcommittee SC 4,
Microbiological methods.
This second edition cancels and replaces the first edition (ISO 17994:2004), which has been technically
revised.
iv © ISO 2014 – All rights reserved
ISO 17994:2014(E)
Introduction
This International Standard specifies criteria and procedures for comparing the average quantitative
results obtained by two microbiological analytical methods, one of which may, but need not, be a
standard or reference method.
The methods considered are based on counts of colonies or of positive and negative liquid enrichment
tubes (MPN).
INTERNATIONAL STANDARD ISO 17994:2014(E)
Water quality — Requirements for the comparison of the
relative recovery of microorganisms by two quantit
...
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