SIST-TS CEN ISO/TS 22117:2011
(Main)Microbiology of food and animal feeding stuffs - Specific requirements and guidance for proficiency testing by interlaboratory comparison (ISO/TS 22117:2010)
Microbiology of food and animal feeding stuffs - Specific requirements and guidance for proficiency testing by interlaboratory comparison (ISO/TS 22117:2010)
This Technical Specification gives requirements and guidance for the organization of proficiency testing schemes for microbiological examinations of: a) food and beverages; b) animal feeding stuffs; c) food production environments and food handling; d) primary production stages. This Technical Specification is also potentially applicable to the microbiological examination of water where water is either used in food production or is regarded as a food in national legislation. This Technical Specification relates to the technical organization and the implementation of proficiency testing schemes, as well as the statistical treatment of the results of microbiological examinations. This Technical Specification is designed for use with ISO/IEC 17043 and ISO 13528, and deals only with areas where specific or additional details are necessary for proficiency testing schemes dealing with microbiological analyses for the areas specified in the first paragraph.
Mikrobiologie von Lebensmitteln und Futtermitteln - Spezielle Anforderungen an die Eignungsprüfung durch Ringversuche (ISO/TS 22117:2010)
Die vorliegende Technische Spezifikation enthält Anforderungen und eine Anleitung für die Organisation von
Eignungsprüfungsprogrammen für die mikrobiologische Untersuchung von:
a) Lebensmitteln und Getränken;
b) Futtermitteln;
c) Umgebung der Lebensmittelproduktion und Handhabung von Lebensmitteln;
d) Primärproduktion.
Diese Technische Spezifikation ist potentiell auch auf die mikrobiologischen Untersuchungen von Wasser
anwendbar, wenn Wasser entweder in der Lebensmittelproduktion verwendet oder in der nationalen Gesetzgebung
als Lebensmittel angesehen wird.
Diese Technische Spezifikation bezieht sich auf die technische Organisation und die Umsetzung von
Eignungsprüfungsprogrammen sowie auf die statistische Behandlung von Ergebnissen mikrobiologischer
Untersuchungen.
Diese Technische Spezifikation ist in Verbindung mit ISO/IEC 17043 und ISO 13528 anzuwenden und
behandelt nur die Gebiete, in denen spezifische oder zusätzliche Einzelheiten für Eignungsprüfungsprogramme
notwendig sind, die sich mit mikrobiologischen Untersuchungen in den im ersten Absatz aufgeführten
Bereichen befassen.
Microbiologie des aliments - Exigences spécifiques et lignes directrices pour les essais d'aptitude par comparaison interlaboratoires (ISO/TS 22117:2010)
L'ISO/TS 22117:2010 fournit des exigences et des recommandations relatives à l'organisation de programmes d'essai d'aptitude pour les examens microbiologiques concernant: a) les aliments et les boissons; b) les aliments pour animaux; c) les environnements de production des aliments et la manipulation de ces aliments; d) les étapes de production primaire.
Éventuellement, l'ISO/TS 22117:2010 peut également s'appliquer à l'examen microbiologique de l'eau si celle-ci est utilisée dans la production alimentaire ou si la législation nationale la considère comme un aliment.
L'ISO/TS 22117:2010 concerne l'organisation technique et la mise en œuvre de programmes d'essai d'aptitude et également le traitement statistique des résultats des examens microbiologiques.
L'ISO/TS 22117:2010 est destinée à être utilisée avec l'ISO/CEI 17043 et l'ISO 13528 et ne traite que des domaines où des détails spécifiques ou supplémentaires sont nécessaires pour les programmes d'essai d'aptitude traitant des analyses microbiologiques pour les domaines spécifiés dans le premier alinéa.
Mikrobiologija živil in krme - Posebne zahteve in napotki za preskušanje strokovnosti z medlaboratorijsko primerjavo (ISO/TS 22117:2010)
Ta tehnična specifikacija podaja zahteve in vodila za organizacijo shem za preskušanje strokovnosti za mikrobiološke preglede: a) hrane in pijače; b) krme; c) okolij za proizvodnjo in ravnanja s hrano; d) začetnih proizvodnih faz. Ta tehnična specifikacija potencialno velja za mikrobiološki pregled vode, kjer je voda uporabljena v proizvodnji hrane ali se šteje za hrano v državni zakonodaji. Ta tehnična specifikacija se nanaša na tehnično organizacijo in izvedbo shem preskušanja strokovnosti in statistično obravnavanje rezultatov mikrobioloških pregledov. Ta tehnična specifikacija je zasnovana za uporabo z ISO/IEC 17043 in ISO 13528 in se ukvarja samo s področji, kjer so potrebne določene ali dodatne podrobnosti za sheme preskušanja strokovnosti, katere obravnavajo mikrobiološke analize za področja, opredeljena v prvem odstavku.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST-TS CEN ISO/TS 22117:2011
01-marec-2011
Mikrobiologija živil in krme - Posebne zahteve in napotki za preskušanje
strokovnosti z medlaboratorijsko primerjavo (ISO/TS 22117:2010)
Microbiology of food and animal feeding stuffs - Specific requirements and guidance for
proficiency testing by interlaboratory comparison (ISO/TS 22117:2010)
Mikrobiologie von Lebensmitteln und Futtermitteln - Spezielle Anforderungen an die
Eignungsprüfung durch Ringversuche (ISO/TS 22117:2010)
Microbiologie des aliments - Exigences spécifiques et lignes directrices pour les essais
d'aptitude par comparaison interlaboratoires (ISO/TS 22117:2010)
Ta slovenski standard je istoveten z: CEN ISO/TS 22117:2010
ICS:
07.100.30 Mikrobiologija živil Food microbiology
SIST-TS CEN ISO/TS 22117:2011 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST-TS CEN ISO/TS 22117:2011
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SIST-TS CEN ISO/TS 22117:2011
TECHNICAL SPECIFICATION
CEN ISO/TS 22117
SPÉCIFICATION TECHNIQUE
TECHNISCHE SPEZIFIKATION
November 2010
ICS 07.100.30
English Version
Microbiology of food and animal feeding stuffs - Specific
requirements and guidance for proficiency testing by
interlaboratory comparison (ISO/TS 22117:2010)
Microbiologie des aliments - Exigences spécifiques et Mikrobiologie von Lebensmitteln und Futtermitteln -
lignes directrices pour les essais d'aptitude par Spezielle Anforderungen an die Eignungsprüfung durch
comparaison interlaboratoires (ISO/TS 22117:2010) Ringversuche (ISO/TS 22117:2010)
This Technical Specification (CEN/TS) was approved by CEN on 9 August 2010 for provisional application.
The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to submit their
comments, particularly on the question whether the CEN/TS can be converted into a European Standard.
CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS available
promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in parallel to the CEN/TS)
until the final decision about the possible conversion of the CEN/TS into an EN is reached.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, 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 COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2010 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN ISO/TS 22117:2010: E
worldwide for CEN national Members.
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SIST-TS CEN ISO/TS 22117:2011
CEN ISO/TS 22117:2010 (E)
Contents Page
Foreword .3
2
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SIST-TS CEN ISO/TS 22117:2011
CEN ISO/TS 22117:2010 (E)
Foreword
This document (CEN ISO/TS 22117:2010) has been prepared by Technical Committee ISO/TC 34 "Food
products" in collaboration with Technical Committee CEN/TC 275 “Food analysis - Horizontal methods” the
secretariat of which is held by DIN.
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.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to announce this Technical Specification: Austria, Belgium, Bulgaria, Croatia, 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 the United Kingdom.
Endorsement notice
The text of ISO/TS 22117:2010 has been approved by CEN as a CEN ISO/TS 22117:2010 without any
modification.
3
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SIST-TS CEN ISO/TS 22117:2011
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SIST-TS CEN ISO/TS 22117:2011
TECHNICAL ISO/TS
SPECIFICATION 22117
First edition
2010-11-01
Microbiology of food and animal feeding
stuffs — Specific requirements and
guidance for proficiency testing by
interlaboratory comparison
Microbiologie des aliments — Exigences spécifiques et lignes
directrices pour les essais d'aptitude par comparaison interlaboratoires
Reference number
ISO/TS 22117:2010(E)
©
ISO 2010
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SIST-TS CEN ISO/TS 22117:2011
ISO/TS 22117:2010(E)
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ii © ISO 2010 – All rights reserved
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SIST-TS CEN ISO/TS 22117:2011
ISO/TS 22117:2010(E)
Contents Page
Foreword .iv
Introduction.v
1 Scope.1
2 Normative references.1
3 Terms and definitions .2
4 Scheme design and purpose .2
4.1 General .2
4.2 Scheme objectives .2
4.3 Laboratory requirements for schemes.3
4.4 Choice of test matrices.3
4.5 Information on test methods used by the PT provider.3
4.6 Statistical design.3
5 Technical requirements and guidance for sample design and content .4
5.1 Target organisms level .4
5.2 Sources, characterization and traceability of organisms .4
5.3 Background and competitive flora .5
5.4 Matrix selection and effects .5
6 Sample verification by the provider .5
6.1 General .5
6.2 Sample homogeneity testing — General considerations.5
6.3 Homogeneity testing for quantitative (enumeration) samples .6
6.4 Homogeneity testing for qualitative methods .7
6.5 Stability testing by the provider.7
7 Sample handling.8
7.1 General .8
7.2 Instructions to participants .8
8 Performance evaluations.9
8.1 General .9
8.2 Preliminary considerations .9
8.3 Quantitative methods.9
8.4 Assessment of qualitative methods.16
Annex A (informative) Example of details to be included in a PT scheme plan.19
Annex B (informative) Methods of testing for variation between portions of test materials .21
Annex C (informative) A practical method to assess long-term performance of participants in PT
schemes using enumeration methods.24
Annex D (informative) Example of a safety data sheet .26
Bibliography.28
© ISO 2010 – All rights reserved iii
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SIST-TS CEN ISO/TS 22117:2011
ISO/TS 22117:2010(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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
In other circumstances, particularly when there is an urgent market requirement for such documents, a
technical committee may decide to publish other types of document:
⎯ an ISO Publicly Available Specification (ISO/PAS) represents an agreement between technical experts in
an ISO working group and is accepted for publication if it is approved by more than 50 % of the members
of the parent committee casting a vote;
⎯ ISO Technical Specification (ISO/TS) represents an agreement between the members of a technical
committee and is accepted for publication if it is approved by 2/3 of the members of the committee casting
a vote.
An ISO/PAS or ISO/TS is reviewed after three years in order to decide whether it will be confirmed for a
further three years, revised to become an International Standard, or withdrawn. If the ISO/PAS or ISO/TS is
confirmed, it is reviewed again after a further three years, at which time it must either be transformed into an
International Standard or be withdrawn.
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.
ISO/TS 22117 was prepared by Technical Committee ISO/TC 34, Food products, Subcommittee SC 9,
Microbiology.
iv © ISO 2010 – All rights reserved
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ISO/TS 22117:2010(E)
Introduction
General requirements for organization of proficiency testing (PT) schemes of all types are given through
ISO/CASCO (Committee on Conformity Assessment) in ISO/IEC 17043; additionally, general guidance is
available from the International Union of Pure and Applied Chemistry (IUPAC, see Reference [9]) and the
International Laboratory Accreditation Cooperation (ILAC, see Reference [8]). However, these
recommendations may not be directly applicable to all cases and should be interpreted specifically for different
laboratory sectors where PT schemes are organized. For this reason, a document is needed to establish the
criteria which a provider (and associated collaborators) of PT schemes shall meet in order to be recognized as
competent to provide PT schemes for microbiological analysis. This applies particularly to the specific
technical requirements necessary to deal with living microorganisms, such as sample homogeneity and
stability, as well as with the interpretation of presence/absence (detection) tests which is not covered by an
existing document.
Proficiency testing schemes for microbiology laboratories are mainly used to evaluate performance,
particularly trueness (bias) and in some cases precision, of food microbiological examinations in specific
laboratories.
Additionally, data from such PT schemes can be used:
a) to provide information to the organizations responsible for laboratory acceptance within an official control
framework and to allow continuous monitoring;
b) to aid laboratory accreditation in a general framework of quality management;
c) to inform those responsible for quality in the participating laboratories as part of the educative elements of
external quality assessment of trueness (bias).
Information from PT schemes may also be used for:
1) identification of the possible sources of errors, particularly the bias component of uncertainty, to
improve performance;
[6]
2) estimation of measurement uncertainty for enumeration methods (see ISO/TS 19036 ) and limits of
detection for presence/absence methods;
3) demonstration of staff competence to perform a specific microbiological examination;
4) evaluation or validation of a given method by the study of trueness and precision;
5) identification of variability between individual laboratories;
6) assignment of a “target” value for an analyte in a material in order to establish a reference material.
However, these aspects are not specifically covered in this Technical Specification.
Proficiency testing schemes are therefore organized to meet certain criteria and the testing programme
(frequency, number of samples, number of repeats, etc.) shall meet the requirements of the type of method
used and commodity analysed, to achieve the level of control desired by all parties involved.
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SIST-TS CEN ISO/TS 22117:2011
TECHNICAL SPECIFICATION ISO/TS 22117:2010(E)
Microbiology of food and animal feeding stuffs — Specific
requirements and guidance for proficiency testing by
interlaboratory comparison
1 Scope
This Technical Specification gives requirements and guidance for the organization of proficiency testing
schemes for microbiological examinations of:
a) food and beverages;
b) animal feeding stuffs;
c) food production environments and food handling;
d) primary production stages.
This Technical Specification is also potentially applicable to the microbiological examination of water where
water is either used in food production or is regarded as a food in national legislation.
This Technical Specification relates to the technical organization and the implementation of proficiency testing
schemes, as well as the statistical treatment of the results of microbiological examinations.
This Technical Specification is designed for use with ISO/IEC 17043 and ISO 13528, and deals only with
areas where specific or additional details are necessary for proficiency testing schemes dealing with
microbiological analyses for the areas specified in the first paragraph.
2 Normative references
The 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 3534-1, Statistics — Vocabulary and symbols — Part 1: General statistical terms and terms used in
probability
ISO 3534-2, Statistics — Vocabulary and symbols — Part 2: Applied statistics
ISO 5725-1, Accuracy (trueness and precision) of measurement methods and results — Part 1: General
principles and definitions
ISO 5725-5, Accuracy (trueness and precision) of measurement methods and results — Part 5: Alternative
methods for the determination of the precision of a standard measurement method
ISO 7218, Microbiology of food and animal feeding stuffs — General requirements and guidance for
microbiological examinations
ISO 13528, Statistical methods for use in proficiency testing by interlaboratory comparisons
ISO/IEC 17043:2010, Conformity assessment — General requirements for proficiency testing
© ISO 2010 – All rights reserved 1
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ISO/TS 22117:2010(E)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 3534-1, ISO 3534-2, ISO 5725-1,
ISO 13528, ISO/IEC 17043 and the following apply.
NOTE 1 Some terms used in the text have different meanings in microbiology and statistics, e.g. homogeneity,
heterogeneity, test, sample, distribution. The context clarifies whether the terms refer to microbiological test samples or
datasets used for statistical analysis.
NOTE 2 Some providers of proficiency testing use the term external quality assessment (EQA) to indicate schemes
with broader application to all areas of operation of a laboratory and a particular educational remit. The requirements of
this Technical Specification cover those EQA activities that meet the definition of proficiency testing.
3.1
target organism
microorganism which is the designated analyte for a proficiency testing sample
3.2
background flora
microorganisms included in a proficiency testing sample which can be introduced to compete with or mimic
the target microorganism
3.3
reference strain
microorganism obtained directly from an official culture collection and defined to at least the genus and
species level, catalogued and described according to its characteristics and preferably originating from food or
water as applicable
[3]
[ISO/TS 11133-1:2009 , 3.3.2]
3.4
recovery percentage
proportion of the assigned value of the target organism recovered by the participant
NOTE 1 The recovery percentage is calculated by multiplying by 100 the number of recovered colony forming units
(cfu) per volume or per mass.
NOTE 2 The recovery percentage can be significantly below 100 % when competitive flora and matrix effects are
present in a proficiency testing sample.
4 Scheme design and purpose
4.1 General
General requirements for designing PT schemes are given in ISO/IEC 17043; in this clause, only areas
requiring special consideration for microbiological PT schemes are discussed in the context of these general
principles.
4.2 Scheme objectives
The primary objective of any PT scheme is to provide information to enable laboratories to have confidence in
the reliability of their results.
The detailed requirements for a documented plan of a PT scheme are covered in ISO/IEC 17043:2010,
4.4.1.3, and the plan should also include reference to any relevant legislation. An example of a plan for a
typical microbiology food examination scheme is given in Annex A.
2 © ISO 2010 – All rights reserved
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ISO/TS 22117:2010(E)
The studies required to establish a new PT scheme are extensive and shall be clearly defined in the scheme
objectives. These should include, as a minimum, the requirements listed in Clause 5. Requirements for
checking individual rounds of testing, including homogeneity and stability testing, should also be established in
the scheme design and be appropriate for the scheme objectives.
4.3 Laboratory requirements for schemes
General requirements for appropriate laboratory facilities to handle all aspects of PT schemes are given in
ISO/IEC 17043:2010, 4.3.1, and safety requirements are covered in ISO/IEC 17043:2010, 4.6.2.4.
For microbiology schemes, providers shall have a documented policy to bring hazards to the attention of
participants and ensure that relevant safety advice is given (see Clause 7). For example, food microbiology
laboratories shall have facilities for dealing with microorganisms of risk categories 1, 2, and 3, as appropriate
(see ISO 7218:2007, 3.2).
4.4 Choice of test matrices
General requirements to document test matrices in the scheme plan are given in ISO/IEC 17043:2010, 4.4.1.3,
and choice of the matrices to reflect routine sample types in ISO/IEC 17043:2010, 4.4.2.3.
The reasons for the choice of matrix type should be stated, e.g. to provide levels of sample stability and
homogeneity that are fit for the intended purpose of the scheme.
The description of the test items shall specify the sample matrix (natural or simulated); whether artificially or
naturally contaminated; the source and country of origin to comply with international transport regulations; and
any method of preservation used, e.g. freeze-dried, air dried.
4.5 Information on test methods used by the PT provider
The general requirements for methods to be used by the PT provider are given in ISO/IEC 17043:2010,
4.4.1.3.
If the scheme is targeted at one or more tests specified in or required by legislation, the routine quality control
tests on the scheme samples (e.g. homogeneity and stability) shall be undertaken in accordance with the
methods stipulated in that legislation and this shall be stated (ISO/IEC 17043:2010, 4.5.1).
Participants shall be encouraged to use their routine methods but, where they are undertaking tests in
accordance with legislation, some degree of guidance shall be given, e.g. reference to ISO methods,
legislative texts, or peer-reviewed publications (ISO/IEC 17043:2010, 4.5.1).
4.6 Statistical design
General requirements for statistical design are given in ISO/IEC 17043:2010, 4.4.4.
An outline of the statistical design for PT schemes for microbiology shall indicate that the statistical tests to be
used are influenced by the level of homogeneity of the test material which, in turn, is influenced by the random
variation in distribution of the microorganisms.
Except for low numbers, a log-normal distribution is usually expected in quantitative testing data and suitable
statistical analysis methods shall be used for such data [ISO/IEC 17043:2010, B.3.1.4 d)]. Where low numbers
are required in quantitative test items (e.g. water or beverage examination), a random Poisson model is more
applicable, as the variation in numbers of organisms between different units of material becomes relatively
large and can mask variations in performance.
Sample homogeneity shall normally be such that it does not significantly influence the observed variation
between laboratories.
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ISO/TS 22117:2010(E)
Semi-quantitative enumeration tests and qualitative detection tests require different statistical methods to
analyse data and these are discussed further in 8.3 and 8.4.
The scheme plan shall clarify distinctions between performance testing for methods for detection and those for
enumeration of target microorganisms.
5 Technical requirements and guidance for sample design and content
5.1 Target organisms level
The target organisms shall be provided at levels suitable to show that examination methods are fit-for-purpose
and to reflect levels likely to be found in the sample matrices being tested (ISO/IEC 17043:2010, 4.4.2.3).
Where pathogenic bacteria are the target, the levels should also take account of and reflect the levels likely to
cause hazard to human health and, if appropriate, any limits specified in microbiological criteria.
NOTE The level causing hazard to human health is not always known with accuracy and depends on the
susceptibility of individuals. The aim of examination for pathogens is to prevent illness, and also to detect pathogens at a
very low level, before those pathogens can grow to a higher level.
For quantitative (enumeration) methods, the target level shall be appropriate for the levels routinely found in
and any statutory specifications applicable to the sample matrices used. The target level should also
sometimes be used near the limit of quantification of routine methods to challenge the performance of the
participants across the applicable range of the method. However, samples should not be dispatched with
organism levels so low that, when using routine dilutions, the expected mean number of organisms in a
sample is fewer than 10 colonies per plate.
For qualitative (detection) methods, the target organisms shall generally be required to be at a sufficiently low
level to provide a valid challenge to the methodology and to contribute data for validation exercises to
establish or verify limits of detection for individual participant laboratories.
5.2 Sources, characterization and traceability of organisms
The characteristics of the target organisms shall be established before use in order reliably to assess
performance, especially in schemes where participants are permitted to use different methodologies.
Both typical and atypical strains should be considered and included in the scheme programme to challenge
laboratory performance.
Recognized reference strains from international collections should be used where they are most suitable for
the scheme purpose; however, laboratory isolates or “wild” strains isolated from the matrices used by PT
schemes are useful to reflect routine situations more closely. Where these are used, they should be
sufficiently characterized according to the appropriate International Standard reference methods, to ensure
that any atypical reactions are apparent to the organizers before use.
In all cases, the organisms used in PT scheme samples should be traceable to the relevant culture collection
or to valid characterization data held by the organizers.
Under certain circumstances, it is not possible to use reference cultures or materials from internationally
recognized collections or cultured laboratory strains, e.g. for PT schemes for non-cultivable organisms such
as human noroviruses. In such circ
...
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