EN ISO 25424:2011

SLOVENSKI STANDARD
01-oktober-2011
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SIST EN 15424:2007
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Sterilization of medical devices - Low temperature steam and formaldehyde -
Requirements for development, validation and routine control of a sterilization process
for medical devices (ISO 25424:2009)
Sterilisation von Medizinprodukten - Niedertemperatur-Dampf- Formaldehyd -
Anforderungen an die Entwicklung, Validierung und Routineüberwachung von
Sterilisationsverfahren für Medizinprodukte (ISO 25424:2009)
Stérilisation des dispositifs médicaux - Formaldéhyde et vapeur à faible température -
Exigences pour le développement, la validation et le contrôle de routine d'un procédé de
stérilisation pour dispositifs médicaux (ISO 25424:2009)
Ta slovenski standard je istoveten z: EN ISO 25424:2011
ICS:
11.080.01 Sterilizacija in dezinfekcija na Sterilization and disinfection
splošno in general
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN ISO 25424
NORME EUROPÉENNE
EUROPÄISCHE NORM
June 2011
ICS 11.080.01 Supersedes EN 15424:2007
English Version
Sterilization of medical devices - Low temperature steam and
formaldehyde - Requirements for development, validation and
routine control of a sterilization process for medical devices (ISO
25424:2009)
Stérilisation des dispositifs médicaux - Formaldéhyde et Sterilisation von Medizinprodukten - Niedertemperatur-
vapeur à faible température - Exigences pour le Dampf- Formaldehyd - Anforderungen an die Entwicklung,
développement, la validation et le contrôle de routine d'un Validierung und Routineüberwachung von
procédé de stérilisation pour dispositifs médicaux (ISO Sterilisationsverfahren für Medizinprodukte (ISO
25424:2009) 25424:2009)
This European Standard was approved by CEN on 3 June 2011.

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, 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
© 2011 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 25424:2011: E
worldwide for CEN national Members.

Contents Page
Foreword .3
Annex ZA (informative) Relationship between this European Standard and the Essential
Requirements of EU Directive 90/385/EEC on Active Implantable Medical Devices .4
Annex ZB (informative) Relationship between this European Standard and the Essential
Requirements of EU Directive 93/42/EEC on Medical Devices .5
Annex ZC (informative) Relationship between this European Standard and the Essential
Requirements of EU Directive 98/79/EC on in vitro diagnostic medical devices .6

Foreword
The text of ISO 25424:2009 has been prepared by Technical Committee ISO/TC 198 “Sterilization of health
care products” of the International Organization for Standardization (ISO) and has been taken over as EN ISO
25424:2011 by Technical Committee CEN/TC 204 “Sterilization of medical devices” the secretariat of which is
held by BSI.
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 December 2011, and conflicting national standards shall be withdrawn
at the latest by December 2011.
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 15424:2007.
This document has been prepared under a mandate given to CEN by the European Commission and the
European Free Trade Association, and supports essential requirements of EU Directives.
For relationship with EU Directives, see informative Annex ZA, ZB and ZC, which are integral parts of this
document.
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, 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 25424:2009 has been approved by CEN as a EN ISO 25424:2011 without any modification.
Annex ZA
(informative)
Relationship between this European Standard and the Essential
Requirements of EU Directive 90/385/EEC on Active Implantable Medical
Devices
This European Standard has been prepared under a mandate given to CEN by the European Commission
and the European Free Trade Association to provide a means of conforming to Essential Requirements of the
New Approach Directive 90/385/EEC on active implantable medical devices.
Once this standard is cited in the Official Journal of the European Union under that Directive and has been
implemented as a national standard in at least one Member State, compliance with the clauses of this
standard given in Table ZA.1 confers, within the limits of the scope of this standard, a presumption of
conformity with the corresponding Essential Requirements of that Directive and associated EFTA regulations.
Table ZA.1 — Correspondence between this European Standard and Directive 90/385/EEC
Clauses of this EN Essential Requirements (ERs) of Qualifying remarks/Notes
Directive 90/385/EEC
4,5,6,7,8,9,10,11,12 7 This relevant Essential Requirement is
only partly addressed in this European
Standard
WARNING — Other requirements and other EU Directives may be applicable to the product(s) falling
within the scope of this Standard.
Annex ZB
(informative)
Relationship between this European Standard and the Essential
Requirements of EU Directive 93/42/EEC on Medical Devices
This European Standard has been prepared under a mandate given to CEN by the European Commission
and the European Free Trade Association to provide a means of conforming to Essential Requirements of the
New Approach Directive 93/42/EEC on medical devices.
Once this standard is cited in the Official Journal of the European Union under that Directive and has been
implemented as a national standard in at least one Member State, compliance with the clauses of this
standard given in Table ZB.1 confers, within the limits of the scope of this standard, a presumption of
conformity with the corresponding Essential Requirements of that Directive and associated EFTA regulations.
Table ZB.1 — Correspondence between this European Standard and Directive 93/42/EEC
Clauses of this EN Essential Requirements (ERs) of Qualifying remarks/Notes
Directive 93/42/EEC
4,5,6,7,8,9,10,11,12 8.3 This relevant Essential Requirement is
only partly addressed in this European
Standard
4,5,6,7,8,9,10,11,12 8.4
WARNING — Other requirements and other EU Directives may be applicable to the product(s) falling
within the scope of this Standard.
Annex ZC
(informative)
Relationship between this European Standard and the Essential
Requirements of EU Directive 98/79/EC on in vitro diagnostic medical
devices
This European Standard has been prepared under a mandate given to CEN by the European Commission
and the European Free Trade Association to provide a means of conforming to Essential Requirements of the
New Approach Directive 98/79/EC on in vitro diagnostic medical devices.
Once this standard is cited in the Official Journal of the European Union under that Directive and has been
implemented as a national standard in at least one Member State, compliance with the clauses of this
standard given in Table ZC.1 confers, within the limits of the scope of this standard, a presumption of
conformity with the corresponding Essential Requirements of that Directive and associated EFTA regulations.
Table ZC.1 — Correspondence between this European Standard and Directive 98/79/EC
Clauses of this EN Essential Requirements (ERs) of Qualifying remarks/Notes
Directive 98/79/EC
4,5,6,7,8,9,10,11,12 B.2.3 This relevant Essential Requirement is
only partly addressed in this European
Standard
4,5,6,7,8,9,10,11,12 B.2.4
WARNING — Other requirements and other EU Directives may be applicable to the product(s) falling
within the scope of this Standard.

INTERNATIONAL ISO
STANDARD 25424
First edition
2009-09-01
Sterilization of medical devices — Low
temperature steam and formaldehyde —
Requirements for development, validation
and routine control of a sterilization
process for medical devices
Stérilisation des dispositifs médicaux — Formaldéhyde et vapeur à
faible température — Exigences pour le développement, la validation et
le contrôle de routine d'un procédé de stérilisation pour dispositifs
médicaux
Reference number
ISO 25424:2009(E)
©
ISO 2009
ISO 25424:2009(E)
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ii © ISO 2009 – All rights reserved

ISO 25424:2009(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 25424 was prepared by CEN (as EN 15424:2007) and is submitted for approval under a special “fast-
track procedure”, by Technical Committee ISO/TC 198, Sterilization of health care products, in parallel with its
approval by the ISO member bodies.
For the purposes of this International Standard, the CEN annex regarding the fulfilment of European Council
Directives has been removed.
ISO 25424:2009(E)
Contents Page
Foreword. vi
Introduction . vii
1 Scope .1
1.1 Inclusions .1
1.2 Exclusions .1
2 Normative references .2
3 Terms and definitions .2
4 Quality management system elements .8
4.1 Documentation.8
4.2 Management responsibility .8
4.3 Product realization.9
4.4 Control of non-conforming product.9
5 Sterilizing agent characterization .9
5.1 General.9
5.2 Sterilizing agent .9
5.3 Microbicidal effectiveness .9
5.4 Material effects.9
5.5 Environmental considerations .10
6 Process and equipment characterization .10
6.1 General.10
6.2 Process .10
6.3 Equipment .11
7 Product definition .11
8 Process definition.12
9 Validation.13
9.1 General.13
9.2 Installation qualification.13
9.3 Operational qualification.14
9.4 Performance qualification.15
9.5 Review and approval of validation.16
10 Routine monitoring and control.17
10.1 General.17
10.2 Biological indicators .17
10.3 Chemical indicators.18
10.4 Records.18
11 Product release from sterilization.18
12 Maintaining process effectiveness .18
12.1 General.18
12.2 Maintenance of equipment .18
12.3 Requalification .19
12.4 Assessment of change.19
Annex A (normative) Process definition based on inactivation of reference microorganisms and
knowledge of bioburden on product items to be sterilized .20
Annex B (normative) Process definition based on inactivation of reference microorganisms.21
iv © ISO 2009 – All rights reserved

ISO 25424:2009(E)
Annex C (informative) Guidance on application of this European Standard.23
Annex D (informative) Environmental aspects regarding development, validation and routine
control of Low Temperature Steam and Formaldehyde processes.33
Bibliography.37

ISO 25424:2009(E)
Foreword
This document (EN 15424:2007) has been prepared by Technical Committee CEN/TC 204 “Sterilization of
medical devices”, the secretariat of which is held by BSI.
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 October 2007, and conflicting national standards shall be withdrawn at
the latest by October 2007.
This document has been prepared under a mandate given to CEN by the European Commission and the
European Free Trade Association, and supports essential requirements of EU Directive(s).
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 United Kingdom.
vi © ISO 2009 – All rights reserved

ISO 25424:2009(E)
Introduction
A sterile medical device is one which is free of viable microorganisms. European Standards, which specify
requirements for validation and routine control of a sterilization process require, when it is necessary to supply
a sterile medical device, that adventitious microbiological contamination of a medical device prior to
sterilization be minimized. Even so, medical devices produced under standard manufacturing conditions in
accordance with the requirements for quality management systems (see EN ISO 13485) or which have been
subjected to a cleaning process as part of their reprocessing in a health care establishment may, prior to
sterilization, have microorganisms on them, albeit in low numbers. Such products are non-sterile. The purpose
of sterilization is to inactivate the microbiological contaminants and thereby transform the non-sterile products
into sterile ones.
The kinetics of inactivation of a pure culture of microorganisms by physical and/or chemical agents used to
sterilize medical devices can generally best be described by an exponential relationship between the numbers
of microorganisms surviving and the extent of treatment with the sterilizing agent; inevitably this means that
there is always a finite probability that a microorganism may survive regardless of the extent of treatment
applied. For a given treatment, the probability of survival is determined by the number and resistance of
microorganisms and by the environment in which the organisms exist during treatment. It follows that the
sterility of any one product in a population subjected to sterilization cannot be guaranteed and the sterility of a
processed population is defined in terms of the probability of there being a viable microorganism present on a
product item.
This standard describes requirements which will enable the demonstration that a low temperature steam and
formaldehyde sterilization process intended to sterilize medical devices has appropriate microbicidal activity,
and that this activity is both reliable and reproducible, such that the relationship for the inactivation of
microorganisms can be extrapolated with reasonable confidence to low levels of probability of there being a
viable microorganism present on a product after sterilization. This standard does not specify the maximal
value to be taken by this probability; specification of this probability is given in EN 556-1.
Requirements of the quality management system for medical device design/development, production,
installation and servicing are given in EN ISO 13485. The standard for quality management systems
recognizes that, for certain processes used in manufacturing or reprocessing, the effectiveness cannot be fully
verified by subsequent inspection and testing of the product. Sterilization is an example of such a process. For
this reason, sterilization processes are validated for use, the performance of the sterilization process
monitored routinely and the equipment maintained.
Exposure to a properly validated, accurately controlled sterilization process is not the only factor associated
with the provision of reliable assurance that the product is sterile and, in this regard, suitable for its intended
use. Attention is therefore given to a number of factors including:
a) the microbiological status of incoming raw materials and/or components,
b) the validation and routine control of any cleaning and disinfection procedures used on the product,
c) the control of the environment in which the product is manufactured, assembled and packaged,
d) the control of equipment and processes,
e) the control of personnel and their hygiene,
f) the manner and materials in which the product is packaged, and,
g) the conditions under which the product is transported and stored.
ISO 25424:2009(E)
The type of contamination on a product to be sterilized varies and this impacts upon the effectiveness of a
sterilization process. Products that have been used in a health care setting and are being presented for
re-sterilization in accordance with the manufacturer's instructions (see EN ISO 17664) should be regarded as
a special case. There is the potential for such products to possess a wide range of contaminating
microorganisms and residual inorganic and/or organic contamination in spite of the application of a cleaning
process. Hence, particular attention has to be given to the validation and control of the cleaning and
disinfection processes used during reprocessing.
The requirements are the normative parts of this standard with which compliance is claimed. The guidance
given in the informative annexes is not normative and is not provided as a checklist for auditors. The guidance
provides explanations as well as methods that are accepted as being suitable means for complying with the
requirements. Approaches other than those given in the guidance may be used, if they are effective in
achieving compliance with the requirements of this European Standard.
The development, validation and routine control of a sterilization process comprise a number of discrete but
interrelated activities, for example calibration, maintenance, product definition, process definition, installation
qualification, operational qualification, and performance qualification. While the activities required by this
standard have been grouped together and are presented in a particular order, this European Standard does
not require that the activities be performed in the order that they are presented. The activities required are not
necessarily sequential, as the programs of development and validation may be iterative. It is possible that
performing these different activities will involve a number of separate individuals and/or organizations, each of
whom undertake one or more of these activities. This European Standard does not specify the particular
individuals or organizations to carry out the activities.
Activities required by this standard might also give rise to an environmental burden that should be considered
and minimized, e.g. by utilizing flexibility in planning. Environmental aspects are addressed in Annex D of this
standard.
viii © ISO 2009 – All rights reserved

INTERNATIONAL STANDARD ISO 25424:2009(E)

Sterilization of medical devices — Low temperature steam and
formaldehyde — Requirements for development, validation and
routine control of a sterilization process for medical devices
1 Scope
1.1 Inclusions
1.1.1 This European Standard specifies requirements for the development, validation and routine control of
a Low Temperature Steam and Formaldehyde (LTSF) sterilization process for medical devices.
NOTE Although the scope of this standard is limited to medical devices, it specifies requirements and provides
guidance that may be applicable to other products and equipment.
1.1.2 This European Standard is intended to be applied by process developers, manufacturers of
sterilization equipment, manufacturers of medical devices to be sterilized and the organizations with
responsibility for sterilizing medical devices. (See EN ISO 14937:2000, Table E.1)
1.1.3 This European Standard covers sterilization processes which use a mixture of low temperature steam
and formaldehyde as sterilant, and which are working below ambient pressure only.
1.2 Exclusions
1.2.1 Sterilization processes validated and controlled in accordance with the requirements of this standard
should not be assumed to be effective in inactivating the causative agents of spongiform encephalopathies
such as scrapie, bovine spongiform encephalopathy and Creutzfeld-Jakob disease. Specific
recommendations have been produced in particular countries for the processing of materials potentially
contaminated with these agents.
1.2.2 This standard does not specify requirements for designating a medical device as “STERILE”. Such
requirements are given in EN 556-1.
1.2.3 This standard does not specify a quality management system for the control of all stages of
production of medical devices.
NOTE It is not a requirement of this standard to have a complete quality management system during manufacture or
reprocessing, but those elements of such a system that are required are normatively referenced at appropriate places in
the text. Attention is drawn to the standards for quality management systems (see EN ISO 13485) that control all stages of
production or reprocessing of medical devices including the sterilization process. Further guidance is given in E.2 of
EN ISO 14937:2000.
1.2.4 This standard does not specify requirements for occupational safety associated with the design and
operation of LTSF sterilization facilities.
NOTE 1 Safety requirements for sterilizers are specified in EN 61010-2-040.
NOTE 2 Attention is also drawn to the existence in some countries of regulations stipulating safety requirements.
ISO 25424:2009(E)
1.2.5 This European Standard does not cover analytical methods for determining levels or residues of
formaldehyde and/or its reaction products.
NOTE 1 Attention is drawn to EN 14180.
NOTE 2 Attention is drawn to the possible existence in some countries of statutory regulation specifying limits for the
level of formaldehyde residues on medical devices and products.
1.2.6 This European Standard does not cover preparatory measures that may be necessary before
sterilization such as cleaning, disinfection and packing.
NOTE For re-sterilizable medical devices, the manufacturer(s) of these devices should supply information on the
preparatory measures (see EN ISO 17664).
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.
EN 14180:2003, Sterilizers for medical purposes — Low temperature steam and formaldehyde sterilizers —
Requirements and testing
EN ISO 11138-1, Sterilization of health care products — Biological indicators — Part 1: General requirements
(ISO 11138-1:2006)
EN ISO 11138-5:2006, Sterilization of health care products — Biological indicators — Part 5: Biological
indicators for low-temperature steam and formaldehyde sterilization processes (ISO 11138-5:2006)
EN ISO 11140, Sterilization of health care products — Chemical indicators (Parts as appropriate)
EN ISO 11737-1, Sterilization of medical devices — Microbiological methods — Part 1: Determination of a
population of microorganisms on products (ISO 11737-1:2006)
EN ISO 11737-2, Sterilization of medical devices — Microbiological methods — Part 2: Tests of sterility
performed in the validation of a sterilization process (ISO 11737-2:1998)
EN ISO 13485, Medical devices — Quality management systems — Requirements for regulatory purposes
(ISO 13485:2003)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
adjustment
correction of a measurement device or system to indicate the value as established by calibration
3.2
aeration
part or parts of the sterilization process in which defined conditions are used such that formaldehyde and its
reaction products are desorbed from the medical device, and which can be performed within the sterilizer,
within a separate room or chamber, or by a combination of the two
[3.3 of EN 14180:2003 ]
2 © ISO 2009 – All rights reserved

ISO 25424:2009(E)
3.3
air removal
removal of air from the sterilizer chamber and sterilization load to facilitate sterilant penetration
[3.3 of EN 14180:2003]
3.4
bioburden
population of viable microorganisms on or in product and/or sterile barrier system
[2.2 of ISO/TS 11139:2006]
3.5
biological indicator (BI)
test system containing viable microorganisms inoculated onto a carrier and contained within a primary pack,
ready for use and providing defined resistance to a specified sterilization process under defined reference
conditions
3.6
calibration
set of operations that establish, under specified conditions, the relationship between values indicated by a
measuring instrument or measuring system, or values represented by a material measure or a reference
material, and the corresponding values realized by standards
[2.4 of ISO/TS 11139:2006]
3.7
change control
assessment and determination of the appropriateness of a proposed alteration to product or procedure
[2.5 of ISO/TS 11139:2006]
3.8
chemical indicator
test system that reveals change in one or more predefined process variables based on a chemical or physical
change resulting from exposure to a process
[2.6 of ISO/TS 11139:2006]
3.9
conditioning
treatment of product within the sterilization cycle, but prior to the holding time, to attain a predetermined
temperature and humidity throughout the sterilization load
[3.7 of EN 14180:2003]
3.10
desorption
removal of the sterilant from the chamber and the load at the end of the exposure time
[3.11 of EN 14180:2003]
3.11
D value
time or dose required to achieve inactivation of 90 % of a population of the test microorganism under stated
conditions
[2.11 of ISO/TS 11139:2006]
NOTE For LTSF sterilization the D value is given in minutes.
ISO 25424:2009(E)
3.12
environmental control
engineering and/or procedural systems to maintain conditions in defined areas within specified limits
NOTE Such systems may include air and fluid filters, surface disinfection, personnel attire and administrative
procedures [2.16 of ISO/TS 11139:2006].
3.13
equilibration time
period which elapses between the attainment of the sterilization temperature at the reference measuring point
and the attainment of the sterilization temperature at all points within the load
[3.13 of EN 14180:2003]
3.14
establish
determine by theoretical evaluation and confirm by experimentation
[2.17 of ISO/TS 11139:2006]
3.15
exposure time
time between introducing the sterilant into the chamber and start of the desorption phase
[3.14 of EN 14180:2003]
3.16
fault
one or more of the process parameters which lies outside of its/their specified tolerance(s)
[2.19 of ISO/TS 11139:2006]
3.17
F value
BIO
product of the logarithm of the initial population of microorganisms and the D value
NOTE The F value may be used to express the “total resistance” of the biological indicator.
BIO
3.18
holding time
period for which the temperature, the steam pressure and the formaldehyde concentration of steam are held
within pre-set values and their tolerances to achieve the required inactivation efficacy in the sterilizer chamber
NOTE The holding time follows immediately after the equilibration time [3.15 of EN 14180:2003].
3.19
inoculated carrier
supporting material on or in which a defined number of test microorganisms have been deposited
3.20
installation qualification [IQ]
process of obtaining and documenting evidence that equipment has been provided and installed in
accordance with its specification
[2.22 of ISO/TS 11139:2006]
4 © ISO 2009 – All rights reserved

ISO 25424:2009(E)
3.21
medical device
instrument, apparatus, implement, machine, appliance, implant, in vitro reagent or calibrator, software,
material or other similar or related article, intended by the manufacturer to be used, alone or in combination,
for human beings for one or more of the specific purpose(s) of:
⎯ diagnosis, prevention, monitoring, treatment or alleviation of disease,
⎯ diagnosis, monitoring, treatment, alleviation of or compensation for an injury,
⎯ investigation, replacement, modification, or support of the anatomy or of a physiological process,
⎯ supporting or sustaining life,
⎯ control of conception,
⎯ disinfection of medical devices,
⎯ providing information for medical purposes by means of in vitro examination of specimens derived from
the human body,
and which does not achieve its primary intended action in or on the human body by pharmacological,
immunological or metabolic means, but which may be assisted in its function by such means
[EN ISO 13485]
3.22
microbicidal solution
aqueous solution containing formaldehyde to feed the vaporizer for generating sterilant in the sterilizer
[3.20 of EN 14180:2003]
NOTE The microbicidal solution usually contains stabilizers i.e. alcohols.
3.23
operational qualification (OQ)
process of obtaining and documenting evidence that installed equipment operates within predetermined limits
when used in accordance with its operational procedures
[2.27 of ISO/TS 11139:2006]
3.24
parametric release
declaration that a product is sterile, based on records demonstrating that the process parameters were
delivered within specified tolerances
[2.29 of ISO/TS 11139:2006]
3.25
performance qualification (PQ)
process of obtaining and documenting evidence that the equipment, as installed and operated in accordance
with operational procedures, consistently performs in accordance with pre-determined criteria and thereby
yields product meeting its specification
[2.30 of ISO/TS 11139:2006]
ISO 25424:2009(E)
3.26
process challenge device (PCD)
item designed to constitute a defined resistance to a sterilization process and used to assess performance of
the process
[2.33 of ISO/TS 11139:2006]
NOTE The device is designed so that an inoculated carrier or chemical indicator can be put in the place which is the
most difficult to reach by sterilizing agent(s). The indicator should not interfere with the function of the process challenge
device.
3.27
process parameter
specified value for a process variable
[2.34 of ISO/TS 11139:2006]
NOTE The specification for a sterilization process includes the process parameters and their tolerances.
3.28
process variable
condition within a sterilization process, changes in which alter microbicidal effectiveness
EXAMPLE Time, temperature, pressure, concentration, humidity, wavelength. [2.35 of ISO/TS 11139:2006].
3.29
product
result of a process
[EN ISO 9000]
NOTE For the purposes of sterilization standards, product is tangible and can be raw material(s), intermediate(s),
sub-assembly (ies) and health care product(s) [2.36 of ISO/TS 11139:2006].
3.30
recognized culture collection
depository authority under the Budapest Treaty on The International Recognition of the Deposit of
Microorganisms for the purpose of Patent and Regulation
[2.38 of ISO/TS 11139:2006]
3.31
reference measuring point
point where the temperature sensor for the sterilization cycle control is located
[3.29 of EN 14180:2003]
3.32
reference microorganism
microbial strain obtained from a recognized culture collection
[2.39 of ISO/TS 11139:2006]
3.33
requalification
repetition of part of validation for the purpose of confirming the continued acceptability of a specified process
[2.40 of ISO/TS 11139:2006]
3.34
residues challenge device
item used to assess the desorption efficacy of the sterilization cycle
6 © ISO 2009 – All rights reserved

ISO 25424:2009(E)
3.35
services
supplies from an external source, necessary for the correct function of sterilizing equipment
EXAMPLE Electricity, water, compressed air, drainage [2.41 of ISO/TS 11139:2006].
3.36
specify
stipulate in detail within an approved document
[2.42 of ISO/TS 11139:2006]
3.37
sterilant
microbicidal agent composed of steam containing formaldehyde
[3.31 of EN 14180:2003]
NOTE Sterilant is generated by vaporizing the microbicidal solution and feeding it into the sterilizer chamber.
3.38
sterilant injection
single or repeated stage beginning with the introduction of sterilant into the evacuated sterilizer chamber and
ending when the set operating pressure has been attained
[3.32 of EN 14180:2003]
3.39
sterile
free from viable microorganisms
[2.43 of ISO/TS 11139:2006]
3.40
sterility
state of being free from viable microorganisms
NOTE In practice, no such absolute statement regarding the absence of microorganisms can be proven
[ISO/TS 11139:2006, 2.45]
3.41
sterilization
validated process used to render a product free from viable microorganisms
NOTE In a sterilization process, the nature of microbial inactivation is described by an exponential function.
Therefore the presence of a viable microorganism(s) on any individual item can be expressed in terms of probability. While
this probability can be reduced to a very low number, it can never be reduced to zero [2.47 of ISO/TS 11139:2006].
3.42
sterilization cycle
predetermined sequence of operating stages performed in a sterilizer for the purpose of sterilization and
desorption
[3.37 of EN 14180:2003]
3.43
sterilization load
product to be, or that has been, sterilized together using a given sterilization process
[2.48 of ISO/TS 11139:2006]
...