SIST EN ISO 7218:2007

SLOVENSKI STANDARD
SIST EN ISO 7218:2007
01-november-2007
Mikrobiologija živil in krmil - Splošna pravila za mikrobiološke preiskave (ISO
7218:2007)
Microbiology of food and animal feeding stuffs - General requirements and guidance for
microbiological examinations (ISO 7218:2007)
Mikrobiologie von Lebensmitteln und Futtermitteln - Allgemeine Anforderungen und
Anleitung für mikrobiologische Untersuchungen (ISO 7218:2007)
Microbiologie des aliments - Exigences générales et recommendations (ISO 7218:2007)
Ta slovenski standard je istoveten z: EN ISO 7218:2007
ICS:
07.100.30 Mikrobiologija živil Food microbiology
SIST EN ISO 7218:2007 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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EUROPEAN STANDARD
EN ISO 7218
NORME EUROPÉENNE
EUROPÄISCHE NORM
August 2007
ICS 07.100.30

English Version
Microbiology of food and animal feeding stuffs - General
requirements and guidance for microbiological examinations
(ISO 7218:2007)
Microbiologie des aliments - Exigences générales et Mikrobiologie von Lebensmitteln und Futtermitteln -
recommendations (ISO 7218:2007) Allgemeine Anforderungen und Anleitung für
mikrobiologische Untersuchungen (ISO 7218:2007)
This European Standard was approved by CEN on 19 April 2007.
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 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 Management Centre has the same status as the
official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, 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: rue de Stassart, 36  B-1050 Brussels
© 2007 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 7218:2007: E
worldwide for CEN national Members.

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EN ISO 7218:2007 (E)
Contents Page
Foreword.3

2

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EN ISO 7218:2007 (E)
Foreword
This document (EN ISO 7218:2007) has been prepared by Technical Committee ISO/TC 34 "Agricultural food
products" in collaboration with Technical Committee CEN/TC 275 "Food analysis - Horizontal methods" 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 February 2008, and conflicting national standards shall be withdrawn
at the latest by February 2008.
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, 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 7218:2007 has been approved by CEN as a EN ISO 7218:2007 without any modification.

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INTERNATIONAL ISO
STANDARD 7218
Third edition
2007-08-15

Microbiology of food and animal feeding
stuffs — General requirements and
guidance for microbiological
examinations
Microbiologie des aliments — Exigences générales et
recommandations




Reference number
ISO 7218:2007(E)
©
ISO 2007

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ISO 7218:2007(E)
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ISO 7218:2007(E)
Contents Page
Foreword. v
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Premises . 2
3.1 General. 2
3.2 Safety considerations. 2
3.3 Laboratory design. 2
3.4 Laboratory areas. 3
3.5 Layout and fittings of the premises. 4
3.6 Cleaning and disinfection . 5
4 Staff . 5
4.1 General. 5
4.2 Competence . 6
4.3 Verification of on-going staff competence. 6
4.4 Hygiene . 6
5 Apparatus and equipment . 6
6 Preparation of glassware and other laboratory materials. 28
6.1 Preparation . 28
6.2 Sterilization/decontamination. 28
6.3 Disposable equipment and materials . 28
6.4 Storage of clean glassware and materials . 28
6.5 Management of sterile glassware and materials . 29
6.6 Use of decontamination and disinfection . 29
6.7 Waste management . 29
6.8 Washing . 30
7 Preparation and sterilization of culture media . 30
8 Laboratory samples. 30
8.1 Sampling. 30
8.2 Transport . 31
8.3 Receipt . 31
8.4 Storage. 32
8.5 Test portion . 32
9 Examination. 32
9.1 Hygienic precautions during analysis. 32
9.2 Preparation of initial suspension and dilutions . 34
10 Enumeration . 34
10.1 General. 34
10.2 Enumeration using a solid medium. 35
10.3 Calculation and expression of results obtained with solid media . 37
10.4 Enumeration of yeasts and moulds. 43
10.5 Enumeration using a liquid medium. 44
11 Detection method (qualitative method) . 49
11.1 General. 49
11.2 Principle. 50
11.3 Measurement of uncertainty. 50
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ISO 7218:2007(E)
12 Confirmatory methods. 50
12.1 General . 50
12.2 Preparation of a pure culture. 50
12.3 Gram’s stain (modified Hucker technique). 50
12.4 Use of biochemical galleries for identification . 52
12.5 Use of nucleic probes for identification . 52
12.6 Serological methods. 53
13 Test report. 53
14 Validation of microbiological methods. 54
14.1 Validation of reference methods . 54
14.2 Validation of alternative methods. 54
14.3 Validation of in-house methods. 54
15 Quality assurance of results/quality control of performance. 54
15.1 Internal quality control . 54
15.2 Reference strains . 54
15.3 External quality assessment (proficiency testing) . 55
Annex A (informative) Properties of some disinfectants. 56
Annex B (normative) Determination of most probable number (MPN). 57
Bibliography . 64

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ISO 7218:2007(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.
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 7218 was prepared by Technical Committee ISO/TC 34, Food products, Subcommittee SC 9,
Microbiology, in collaboration with CEN Technical Committee CEN/TC 275, Food analysis — Horizontal
methods.
This third edition cancels and replaces the second edition (ISO 7218:1996), which has been technically
revised. It also incorporates the Amendment ISO 7218:1996/Amd.1:2001.
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ISO 7218:2007(E)
Introduction
When conducting microbiological examinations, it is especially important that
⎯ only those microorganisms which are present in the samples are isolated and enumerated;
⎯ the microorganisms do not contaminate the environment.
In order to achieve this, it is necessary to pay attention to personal hygiene and to use working techniques
which ensure, as far as possible, exclusion of extraneous contamination.
Since, in this International Standard, it is possible to give only a few examples of the precautions to be taken
during microbiological examinations, a thorough knowledge of the microbiological techniques and of the
microorganisms involved is essential. It is important that the examinations are conducted as accurately as
possible, including monitoring and recording aspects that may affect results and calculation of the number of
microorganisms and the uncertainty of the results.
Ultimately, it is the responsibility of the head of the laboratory to judge whether the manipulations are safe and
can be considered to be good laboratory practice.
A large number of manipulations can, for example, unintentionally lead to cross-contamination, and the
analyst should always verify the accuracy of the results given by his or her technique.
In order to conduct the examinations correctly, it is necessary to take certain precautions when constructing
and equipping the laboratory.
Certain precautions must be taken, not only for reasons of hygiene, but also to ensure good reproducibility of
the results. It is not possible to specify all the precautions to be taken in all circumstances, but this
International Standard at least provides the main measures to be taken when preparing, sterilizing, storing the
media, and using the equipment.
If the guidance given in this International Standard is followed, this will also contribute towards maintaining the
health and safety of personnel. Additional information on this subject is to be found in the literature listed in the
Bibliography.
In order to distinguish the guidance in this International Standard, it has been printed in a different typeface
(Times New Roman).

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INTERNATIONAL STANDARD ISO 7218:2007(E)

Microbiology of food and animal feeding stuffs — General
requirements and guidance for microbiological examinations
1 Scope
This International Standard gives general requirements and guidance/options intended for three main uses:
⎯ implementation of ISO/TC 34/SC 9 or ISO/TC 34/SC 5 standards for detection or enumeration of
microorganisms, named hereafter “specific standards”;
⎯ good laboratory practice for food microbiological laboratories (the purpose is not to detail them in this
International Standard, manuals are available for that purpose);
⎯ guidance for accreditation of food microbiological laboratories (this International Standard describes the
technical requirements according to Annex B of ISO/IEC 17025:2005 for the accreditation of a
microbiological laboratory by national organizations).
The requirements of this International Standard supersede the corresponding ones of existing specific
standards.
Additional instructions in the field of molecular biology examinations are specified in ISO 22174.
This International Standard covers examination for bacteria, yeasts and moulds and can be used if
supplemented with specific guidance for prions, parasites and viruses. It does not cover the examination for
toxins or other metabolites (e.g. amines) from microorganisms.
This International Standard applies to the microbiology of food, animal feeding stuffs, the food production
environment and the primary production environment.
The purpose of this International Standard is to help to ensure the validity of food microbiology examinations,
to assist in ensuring that the general techniques used for conducting these examinations are the same in all
laboratories, to help achieve homogeneous results in different laboratories, and to contribute towards the
safety of the laboratory personnel by preventing risks of infection.
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 835 (all parts), Laboratory glassware — Graduated pipettes
ISO 6887 (all parts), Microbiology of food and animal feeding stuffs — Preparation of test samples, initial
suspension and decimal dilutions for microbiological examination
ISO 8199, Water quality — General guidance on the enumeration of micro-organisms by culture
ISO 8261, Milk and milk products — General guidance for the preparation of test samples, initial suspensions
and decimal dilutions for microbiological examination
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ISO 7218:2007(E)
ISO 8655-1, Piston-operated volumetric apparatus — Part 1: Terminology, general requirements and user
recommendations
ISO/TS 11133 (all parts), Microbiology of food and animal feeding stuffs — Guidelines on preparation and
production of culture media
ISO 16140, Microbiology of food and animal feeding stuffs — Protocol for the validation of alternative methods
ISO/TS 19036, Microbiology of food and animal feeding stuffs — Guidelines for the estimation of
measurement uncertainty for quantitative determinations
ISO 22174, Microbiology of food and animal feeding stuffs — Polymerase chain reaction (PCR) for the
detection of food-borne pathogens — General requirements and definitions
3 Premises
3.1 General
This clause gives general requirements, e.g. the principles of design and organization, for the layout of a
microbiological laboratory.
Examination of primary production stage samples (especially for sample reception and sample preparation)
shall be separated from examination of other samples to reduce the risks of cross-contamination.
3.2 Safety considerations
The laboratory design shall comply with safety requirements which will depend on the type of microorganism.
To this end, microorganisms are classified in four risk categories:
⎯ Risk category 1 (no or very low risk to the individual and to the community).
A microorganism that is unlikely to cause human or animal disease.
⎯ Risk category 2 (moderate risk to the individual, low risk to the community).
A pathogen that can cause human or animal disease but is unlikely to be a serious hazard to laboratory
workers, the community or the environment. Laboratory exposures may cause serious human infection,
but effective treatment and preventive measures are available and the risk of spread of infection is limited.
⎯ Risk category 3 (high risk to the individual, low risk to the community).
A pathogen that usually causes serious human or animal disease but does not ordinarily spread from one
infected individual to another. Effective treatment and preventive measures are available.
⎯ Risk category 4 (high risk to the individual and to the community).
A pathogen that usually causes serious human or animal disease and that can be readily transmitted from
one individual to another, directly or indirectly. Effective treatment and preventive measures are not
usually available.
WARNING — Refer to national regulations which will define, in particular, the risk category of the
microorganisms encountered within the boundaries of the country concerned.
3.3 Laboratory design
The guidelines for laboratory layout described below cover examinations for the detection of microorganisms
belonging to risk category 1, 2 and 3 for food microbiology.
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ISO 7218:2007(E)
It should be noted that additional safety measures may be necessary depending on local legislation.
3.4 Laboratory areas
3.4.1 General
The laboratory comprises areas associated with samples and testing (see 3.4.2) and general areas
(see 3.4.3). These shall be separated.
3.4.2 Areas associated with samples and testing
It is considered good practice to have separate locations, or clearly designated areas, for the following:
⎯ receipt and storage of samples;
⎯ preparation of samples, particularly in the case of raw materials (e.g. powdered products containing a high number
of microorganisms);
⎯ examination of samples (from the initial suspension), including incubation of microorganisms;
⎯ manipulation of presumptive pathogens;
⎯ storage of reference and other strains;
⎯ preparation and sterilization of culture media and equipment;
⎯ storage of culture media and reagents;
⎯ examination of foodstuffs for sterility;
⎯ decontamination;
⎯ cleaning of glassware and other equipment;
⎯ storage of hazardous chemicals, preferably kept in specially designated cabinets, cupboards, rooms or buildings.
3.4.3 General areas
Separate areas should be considered for the following:
⎯ entrances, corridors, stairways, lifts;
⎯ administrative areas (e.g. secretarial, offices, documentation rooms, etc.);
⎯ cloakrooms and toilets;
⎯ archive rooms;
⎯ stores;
⎯ rest rooms.
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ISO 7218:2007(E)
3.5 Layout and fittings of the premises
3.5.1 Objectives
The objective is to ensure that the environment within which the microbiological examinations are carried out
does not affect the reliability of the test results.
Arrange the premises so as to avoid risk of cross-contamination. Ways to achieve this objective are, for
example:
a) to construct the laboratory according to the “no way back” layout principle;
b) to carry out procedures in a sequential manner using appropriate precautions to ensure test and sample
integrity (e.g. use of sealed containers);
c) to separate activities in time or space.
Avoid extreme conditions such as excess temperature, dust, humidity, steam, noise, vibration, etc.
Space should be sufficient to allow work areas to be kept clean and tidy. The space required should be commensurate
with the volume of analyses handled and the overall internal organization of the laboratory. The space should be as
required by national regulations, when such exist.
3.5.2 Fittings
The test premises should be constructed and equipped in the following ways in order to reduce the risk of contamination
by dust and therefore by microorganisms (for risk category 3 microorganisms, refer to national regulations).
a) The walls, ceilings and floors should be smooth, easy to clean and resistant to detergents and disinfectants used in
laboratories.
b) Floors should be slip-resistant.
c) Overhead pipes conveying fluids should not cross the premises unless they are hermetically enclosed. Any other
overhead structures should be covered or readily accessible for regular cleaning.
d) Windows and doors should be able to be closed when conducting the tests in order to minimize draughts.
Furthermore, they should be designed so as to avoid the formation of dust traps and thus facilitate their cleaning.
The ambient temperature (18 °C to 27 °C) and air quality (microorganism content, dust spreading rate, etc.) should
be compatible with carrying out the tests. A filter ventilation system for incoming air and for outgoing air is
recommended for this purpose.
e) An adequate extraction system should be installed to prevent exposure to dust arising from handling of dehydrated
culture media, and dusty or powdered samples.
f) When tests are to be conducted in a low-contamination atmosphere, the room should be specially equipped with a
clean laminar airflow cabinet and/or a safety cabinet.
g) If necessary, the laboratory environment should be protected from the harmful effects of solar radiation by use of
shutters or suitably treated glass panels. Internally installed blinds are not suitable as they may be difficult to clean
and could become a source of dust.
3.5.3 Other points
The following points should be consid
...