EN ISO 15883-4:2009

SLOVENSKI STANDARD
01-september-2009
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SIST EN ISO 15883-4:2008
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Washer-disinfectors - Part 4: Requirements and tests for washer-disinfectors employing
chemical disinfection for thermolabile endoscopes (ISO 15883-4:2008)
Reinigungs-Desinfektionsgeräte - Teil 4: Anforderungen und Prüfverfahren für
Reinigungs-Desinfektionsgeräte mit chemischer Desinfektion für thermolabile Endoskope
(ISO 15883-4:2008)
Laveurs désinfecteurs - Partie 4: Exigences et essais pour laveurs désinfecteurs
destinés à la désinfection chimique des endoscopes thermolabiles (ISO 15883-4:2008)
Ta slovenski standard je istoveten z: EN ISO 15883-4:2009
ICS:
11.080.10 Sterilizacijska oprema Sterilizing equipment
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN ISO 15883-4
NORME EUROPÉENNE
EUROPÄISCHE NORM
June 2009
ICS 11.080.10 Supersedes EN ISO 15883-4:2008
English Version
Washer-disinfectors - Part 4: Requirements and tests for
washer-disinfectors employing chemical disinfection for
thermolabile endoscopes (ISO 15883-4:2008)
Laveurs désinfecteurs - Partie 4: Exigences et essais pour Reinigungs-Desinfektionsgeräte - Teil 4: Anforderungen
les laveurs désinfecteurs destinés à la désinfection und Prüfverfahren für Reinigungs-Desinfektionsgeräte mit
chimique des endoscopes thermolabiles (ISO 15883- chemischer Desinfektion für thermolabile Endoskope (ISO
4:2008) 15883-4:2008)
This European Standard was approved by CEN on 16 May 2009.
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: Avenue Marnix 17, B-1000 Brussels
© 2009 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 15883-4:2009: 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 93/42/EEC .4

Foreword
The text of ISO 15883-4:2008 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
15883-4:2009 by Technical Committee CEN/TC 102 “Sterilizers for medical purposes” 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 December 2009, and conflicting national standards shall be withdrawn
at the latest by March 2010.
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 15883-4:2008.
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 EC Directive.
For relationship with EC Directive, see informative Annex ZA, which is an integral part 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, 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 15883-4:2008 has been approved by CEN as a EN ISO 15883-4:2009 without any
modification.
Annex ZA
(informative)
Relationship between this European Standard and the Essential Requirements of
EU Directive 93/42/EEC
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 Communities 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 93/42/EEC on medical
devices
Clauses/subclauses of Essential requirements (ERs) of EU Qualifying remarks/Notes
this International Directive 93/42/EEC
Standard
4.1.1
1, 2, 3, 4, 5, 6, 7.1, 7.2, 7.3, 7.5, 7.6, 8.1, 9.1, The WD shall comply with the
9.2, 9.3, 12.1, 12.5, 12.6, 12.7.1, 12.7.3, 12.7.5, requirements of ISO 15883-
13.1, 13.3, 13.4, 13.6 1:2006
4.1.2
1, 3, 4, 6, 7.1, 7.2, 7.5, 8.1, 9.1
4.1.3 1, 3, 4, 6, 7.1,7.2, 7.5, 8.1, 9.1
4.1.4 13.3 i), 13.3 k)
4.1.5 7.3, 8.1
4.1.6 7.3, 8.1
3, 7.3, 8.1, 9.1
4.1.7
4.1.8
13.4, 13.6 h), 13.3 k), 13.3 m)
4.2 3, 7.3, 7.5, 7.6, 8.1
4.3 3, 8.1
4.4 3, 8.1
4.5 3, 8.1
4.6 3, 8.1
4.7 3, 8.1
4.8
3, 9.1, 9.2
4.9 13.1, 13.6 d)
5.1
3, 9.1, 12.7.5
Table ZA.1 (continued)
Clauses/subclauses of this Essential requirements (ERs) Qualifying remarks/Notes
European Standard of EU Directive 93/42/EEC
5.2 3, 8.1, 13.1
5.3 7.2, 7.5, 8.1
5.4 3, 8.1
5.5 3, 8.1
5.6 2, 3
6.2 1, 2, 3, 6, 7.1, 8.1 Testing for conformity
6.3 3, 9.1 Testing for conformity
6.4 3, 7.3, 8.1, 9.1 Testing for conformity
6.5 3, 7.5, 8.1, 9.1 Testing for conformity
6.6 3, 7.5, 8.1 Testing for conformity
6.7 3, 8.1 Testing for conformity
6.8 3, 8.1 Testing for conformity
6.9 3, 8.1 Testing for conformity
6.10 3, 8.1 Testing for conformity
6.11 3, 8.1 Testing for conformity
6.12 3, 8.1
7 13 The requirements of ISO 15883-1:2006
apply.
8 13.1, 13.3, 13.4, 13.6 In addition, the requirements of
ISO 15883-1:2006 apply.
9 5, 13 The requirements of ISO 15883-1:2006
apply.
10 1, 3 In addition, the requirements of
ISO 15883-1:2006 apply.
- 12.1a) This relevant Essential Requirement is
not addressed in this European
Standard
7, 8, 9 13.3 a) This relevant Essential Requirement is
partly addressed in this European
Standard
- 13.6 q) This relevant Essential Requirement is
not 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.
For devices which are also machinery within the meaning of Article 2(a) of Directive 2006/42/EC on Machinery,
in accordance with Article 3 of Directive 93/42/EEC the following table ZA.2 details the relevant essential
requirements of Directive 2006/42/EC on Machinery to the extent to which they are more specific than those
of Directive 93/42/EEC along with the corresponding clauses of this European Standard. Table ZA.2,
however, does not imply any citation in the OJEU under the machinery directive and thus does not provide
presumption of conformity for the machinery directive.
Table ZA.2 – Relevant Essential Health and Safety Requirements from Directive 2006/42/EC on
machinery that are addressed by this European Standard
(according to article 3 of amended Directive 93/42/EEC)
Clause(s)/sub-clause(s) of this Essential Health and Safety Qualifying remarks/Notes
EN Requirements (EHSRs) of
Directive 2006/42/EC
4.1.1 1.1.7, 1.2.2, 1.2.3, 1.2.4, 1.2.5, 1.3.2, This relevant EHSR are
1.3.3, 1.3.4, 1.5.1, 1.5.2, 1.5.3, 1.5.5, addressed in this Standard
1.5.6, 1.5.8, 1.5.13, 1.5.14, 1.6.2,
1.6.3, 1.6.4, 1.6.5
4.1.1 1.1.3, 1.1.5, 1.1.6, 1.2.1, 1.2.6, 1.3.1, This relevant EHSR are partly
1.3.7, 1.3.8.1, 1.3.8.2, 1.5.4, 1.6.1, addressed in this Standard
1.7.1, 1.7.2, ,1.7.3, 1.7.4
1.3.9, 1.4.1, 1.4.2, 1.4.3, 1.5.9, 4 This relevant EHSR are not
addressed in this Standard
INTERNATIONAL ISO
STANDARD 15883-4
First edition
2008-05-01
Washer-disinfectors —
Part 4:
Requirements and tests for washer-
disinfectors employing chemical
disinfection for thermolabile endoscopes
Laveurs désinfecteurs —
Partie 4: Exigences et essais pour les laveurs désinfecteurs destinés à
la désinfection chimique des endoscopes thermolabiles

Reference number
ISO 15883-4:2008(E)
©
ISO 2008
ISO 15883-4:2008(E)
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ii © ISO 2008 – All rights reserved

ISO 15883-4:2008(E)
Contents Page
Foreword. v
Introduction . vi
1 Scope . 1
2 Normative references . 2
3 Terms and definitions. 2
4 Performance requirements . 3
4.1 General. 3
4.2 Systems for leak testing . 4
4.3 Cleaning. 6
4.4 Disinfecting . 7
4.5 Final (post-disinfection) rinsing . 9
4.6 Purging to remove rinse water. 9
4.7 Drying. 9
4.8 Self-disinfection. 10
4.9 Water treatment equipment . 11
5 Mechanical and process requirements . 12
5.1 Materials ― Design, manufacture and construction. 12
5.2 Device channel irrigation system. 12
5.3 Venting and drainage systems. 13
5.4 Temperature control. 14
5.5 Process chemicals. 14
5.6 Process verification. 14
5.7 Dosing systems . 14
6 Testing for conformity. 14
6.1 General. 14
6.2 Test equipment . 15
6.3 Water used for final (post-disinfection) rinsing. 15
6.4 Hardness of water used during type testing. 15
6.5 Leak test . 16
6.6 Channels non-obstruction test. 18
6.7 Channels non-connection test . 19
6.8 Load dryness. 20
6.9 Thermometric tests. 20
6.10 Chemical dosing tests. 21
6.11 Tests of cleaning efficacy . 22
6.12 Test of disinfection efficacy . 23
7 Documentation and inspection . 27
8 Information to be supplied by the manufacturer. 27
9 Marking, labelling and packaging . 28
10 Information to be requested from the purchaser by the manufacturer . 28
Annex A (informative) Summary of activities covered by this Part of ISO 15883. 29
Annex B (normative) Microbiological testing of the efficacy of chemical disinfection of the load. 31
Annex C (informative) Summary of test programmes . 34
Annex D (normative) Methods for microbiological evaluation of disinfection of liquid transport
system. 35
ISO 15883-4:2008(E)
Annex E (normative) Tests for microbial contamination of post-disinfection rinse water. 40
Annex F (informative) Typical specifications of trumpet valves and connection ports. 41
Annex G (informative) Additional notes on microbiological testing of chemical disinfection
processes. 46
Bibliography . 48

iv © ISO 2008 – All rights reserved

ISO 15883-4:2008(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 15883-4 was prepared by Technical Committee ISO/TC 198, Sterilization of health care products.
ISO 15883 consists of the following parts, under the general title Washer-disinfectors:
⎯ Part 1: General requirements, terms and definitions and tests
⎯ Part 2: Requirements and tests for washer-disinfectors employing thermal disinfection for surgical
instruments, anaesthetic equipment, bowls, dishes, receivers, utensils, glassware, etc.
⎯ Part 3: Requirements and tests for washer-disinfectors employing thermal disinfection for human waste
containers
⎯ Part 4: Requirements and tests for washer-disinfectors employing chemical disinfection for thermolabile
endoscopes
⎯ Part 5: Test soils and methods for demonstrating cleaning efficacy
ISO 15883-4:2008(E)
Introduction
It is recommended that this introduction be read in conjunction with the introduction to ISO 15883-1.
The washer-disinfectors specified in this part of ISO 15883 are intended to process devices which can be
immersed in water or aqueous solutions. For some devices this will require that, prior to processing, relevant
parts of the device are protected from immersion in accordance with the device manufacturer’s operating
instructions.
Fields of application within the scope of the ISO 15883 series include laboratory, veterinary, dental and
pharmaceutical applications and other specific applications, such as washer-disinfectors for bedsteads and
transport carts and the disinfection of crockery and cutlery intended for use with immunologically
compromised patients.
Requirements for washer-disinfectors for other applications are specified in other parts of ISO 15883.
Safety requirements for washer-disinfectors are given in IEC 61010-2-040.
With respect to the potential adverse effects on the quality of water intended for human consumption caused
by the washer-disinfectors:
a) note that, until verifiable European criteria are adopted, existing national regulations concerning the use
and/or the characteristics of the washer-disinfectors remain in force;
b) this part of ISO 15883 provides no information as to whether the washer-disinfectors may be used without
restriction in any of the member states of the EU or EFTA.

vi © ISO 2008 – All rights reserved

INTERNATIONAL STANDARD ISO 15883-4:2008(E)

Washer-disinfectors —
Part 4:
Requirements and tests for washer-disinfectors employing
chemical disinfection for thermolabile endoscopes
1 Scope
This part of ISO 15883 specifies the particular requirements, including performance, for washer-disinfectors
(WDs) that are intended to be used for cleaning and chemical disinfection of thermolabile endoscopes.
This part of ISO 15883 also specifies the performance requirements for the cleaning and disinfection of the
washer-disinfector and its components and accessories which may be required to achieve the necessary
performance.
The methods, instrumentation and instructions required for type testing, works testing, validation (installation,
operational and performance qualification on first installation), routine control and monitoring and re-validation,
periodically and after essential repairs, are also specified.
NOTE 1 In addition, Annex A gives guidance on an appropriate division of responsibility for the range of activities
covered by this part of ISO 15883.
NOTE 2 WDs complying with this part of ISO 15883 can also be used for cleaning and chemical disinfection of other
thermolabile re-usable medical devices for which the device manufacturer has recommended this method of disinfection.
WDs complying with the requirements of this part of ISO 15883 are not intended for cleaning and disinfection
of medical devices, including endoscopic accessories, which are heat stable and can be disinfected or
sterilized by thermal methods (see ISO 15883-1:2006, 4.1.5).
The specified performance requirements of this part of ISO 15883 may not ensure the inactivation or removal
of the causative agent(s) (prion protein) of transmissible spongiform encephalopathies.
NOTE 3 If it is considered that prion protein might be present, particular care is needed in the choice of disinfectants
and cleaning agents to ensure that the chemicals used do not react with the prion protein in a manner that may inhibit its
removal or inactivation from the load or washer-disinfector.
This part of ISO 15883 can be used by prospective purchasers and manufacturers as the basis of agreement
on the specification of WD manufacturers of endoscopes, cleaning products, disinfecting products, and also
by users.
ISO 15883-4:2008(E)
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 11731-2, Water quality — Detection and enumeration of Legionella — Part 2: Direct membrane filtration
method for waters with low bacterial counts
ISO 15883-1:2006, Washer-disinfectors — Part 1: General requirements, terms and definitions and tests
ISO/TS 15883-5:2005, Washer-disinfectors — Part 5: Test soils and methods for demonstrating cleaning
efficacy
IEC 61010-2-040, Safety requirements for electrical equipment for measurement, control, and laboratory
use ― Part 2-040: Particular requirements for sterilizers and washer-disinfectors used to treat medical
materials
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 15883-1 and the following apply.
3.1
air break
physical separation in water supply pipes to prevent back syphonage into the water supply from a device
connected to it
NOTE See EN 1717.
3.2
inoculated carrier
supporting material on or in which a defined number of viable test organisms has been deposited
[ISO 11138-1:2006, definition 3.10]
3.3
leak test
test intended to establish that the surface covering the device and/or lining a device channel is intact to the
extent necessary to maintain a slightly positive pressure
3.4
liquid transport systems
those components of the washer-disinfector used to store, pump or transport water and/or solutions within the
washer-disinfector, excluding pipework before the air break
3.5
microbial inactivation factor
measured change in microbial population, expressed as log , caused by the lethal effect of the disinfectant
3.6
microbial reduction factor
measured change in microbial population expressed as log caused by the combination of the microbial
inactivation factor and the physical removal of microorganisms
3.7
obstruction
partial or complete blockage
2 © ISO 2008 – All rights reserved

ISO 15883-4:2008(E)
3.8
self-disinfection cycle
operating cycle under the control of the automatic controller, for use without any load in the washer-disinfector,
which is intended to disinfect all liquid transport systems’ piping, chamber(s), tanks and other components
which come into contact with the water and/or solutions used for cleaning, disinfecting and rinsing the load
NOTE This does not include disinfection of any pipework between the disinfectant supply and the control valve,
where single-use, multi-dose containers are used to provide process chemicals for use in the washer-disinfector.
3.9
thermolabile
damaged by exposure to temperatures within the range used for thermal disinfection
NOTE The minimum temperature for thermal disinfection specified in ISO 15883-1 is 65 °C.
4 Performance requirements
4.1 General
4.1.1 The WD shall conform to ISO 15883-1:2006 with the exception of the following subclauses:
⎯ 4.2.3 (washing stage);
⎯ 4.3.1 (specification for thermal disinfection);
⎯ 5.3.2.5 (microbial quality of final rinse water);
⎯ 6.4.2 (test for quality of final rinse water);
⎯ 6.5.6 (test for chamber venting to prevent pressurization by steam);
⎯ 6.7.2 (tests on trolleys for handling loads outside the WD);
⎯ 6.8.2 (load temperature test);
⎯ 6.10 (cleaning efficacy test; 6.10.2 modified by 6.11 of this part of ISO 15883).
NOTE These subclauses have been replaced or modified in this part of ISO 15883.
4.1.2 Each device, including any device channels and/or cavities, shall be processed by the WD as follows:
a) leak testing (where appropriate) in accordance with 4.2;
b) cleaning (which may include several stages) in accordance with 4.3;
c) disinfecting in accordance with 4.4;
d) final rinsing in accordance with 4.5;
e) purging of rinse water in accordance with 4.6;
f) drying (when appropriate) in accordance with 4.7.
ISO 15883-4:2008(E)
4.1.3 After the complete process in the WD the endoscope shall be free from vegetative bacteria (but not
necessarily spores) and other contamination. The combination of the cleaning process and the disinfection
process shall be designed to achieve this condition, recognising the high level of bacterial contamination that
may exist, see Bibliography [24], [25] and [26]. It shall be necessary to take into account other factors such as
the design of connectors. The WD manufacturer shall demonstrate this capability during type testing for all the
types of endoscope that the WD is designed to process.
NOTE 1 Demonstration of the capability of the complete cycle may be provided during type testing by employing a
modification of the method described in Annex B, using the organism previously established as most resistant to the
disinfectant, with real endoscope(s) and/or the method given in ISO/TS 15883-5:2005, Annex I.
NOTE 2 The efficacy of the process (including cleaning and disinfection) depends on a number of factors which include
a) the nature (characteristics) of the device being processed;
b) the extent and nature of the soiling to be removed;
c) the temperature;
d) the mechanical energy (type, output);
e) purging to remove rinse water;
f) the detergent system;
g) the nature, volume, concentration and temperature of the cleaning and disinfectant solutions and their ability to wet
the surfaces to be cleaned and disinfected;
h) the duration of the various process stages;
i) the removal of suspended soil.
4.1.4 The WD manufacturer’s instructions shall recommend that any requirements, e.g. for manual cleaning
and or disassembly of the endoscope, prior to processing in the WD, provided by the device manufacturer
should be followed.
4.1.5 The value of any process variable that affects the efficacy of the cycle shall be pre-set and adjustment
shall require the use of a key, code or tool (see also ISO 15883-1:2006, 5.18.3, 5.18.8 and 5.18.12).
4.1.6 The means to control the volume of process chemicals admitted shall deliver the set volume to an
accuracy of ± 5 % or better.
4.1.7 When the WD uses two or more different process chemicals, means shall be provided to ensure that
connection is made to the correct container of process chemical.
NOTE The labelling and/or colour coding of connectors, containers and/or tubes alone may not be sufficient to meet
the requirement.
4.1.8 The WD manufacturer’s instructions shall recommend that heat-stable endoscopic accessories to
thermolabile devices should be thermally disinfected and/or sterilized. [See 8 j) and ISO 15883-1:2006, 4.1.5].
4.2 Systems for leak testing
4.2.1 The requirements of 4.2 shall apply only to WDs intended to process endoscopes which require a test
to verify that the device is watertight.
NOTE This test is intended to demonstrate that the endoscope will not be damaged by liquid ingress during the WD
operating cycle. It is regarded only as a test of the integrity of the endoscope when all parameters of the WD leak test
(e.g. pressure, duration, maximum leak accepted) are consistent with those specified by the endoscope manufacturer.
4 © ISO 2008 – All rights reserved

ISO 15883-4:2008(E)
4.2.2 The WD shall be provided with either
a) means to carry out an automatic leak test on the endoscope which shall be completed before the load
comes into contact with process fluids in the WD
or
b) instructions for use that include the requirement to carry out the test manually prior to processing through
the WD.
NOTE 1 An alternative method specified by the endoscope manufacturer can be used for determining the integrity of
the endoscope when appropriate.
NOTE 2 WDs with an automatic leak test can include a user selectable option to repeat the leak test at the end of the
process and/or independently of a normal process cycle.
4.2.3 For WDs having an automatic leak test, the automatic controller shall prevent the continuation of the
operating cycle and operate an audible and visible alarm indicating a leak test failure if a leak is detected in an
endoscope.
Variations in temperature may adversely affect the sensitivity of the leak test and the WD manufacturer should
state the temperature range permitted in the WD during the automatic leak test, if fitted [see 8 f)].
NOTE 1 A leak test failure indicates that the device is likely to be damaged by further processing; a satisfactory leak
test does not provide absolute assurance that the device will not be damaged by further processing.
NOTE 2 An automatic leak test which maintains a positive pressure throughout the cycle can provide an additional
safety level.
4.2.4 In WDs provided with an automatic leak test:
⎯ the systems for connection of the device to the WD shall be designed so that the fittings provided by the
WD manufacturer and intended for irrigation of the endoscope channel(s) cannot be connected to the
endoscope leak test connector;
⎯ the connection system between the endoscope and the WD shall be designed so that the leak test
connector on the WD cannot be connected to the endoscope channel(s) to be irrigated;
⎯ the means used to monitor the pressure inside the device (e.g. pressure transducer) shall be independent
from the means used to control the initial pressure (e.g. pressure regulating valve);
⎯ the system used to pressurize the device during each leak test shall be provided with a means of
preventing over-pressurization of the device in the event of failure of the pressure control system;
⎯ the extent and duration of pressurization and the pressure drop or air flow which will be used to indicate a
failure shall be either in accordance with the device manufacturer’s instructions for the devices which the
WD is intended to process, or independently verified by the WD manufacturer.
4.2.5 For WDs with an automatic leak test, means shall be provided to automatically warn the user with an
audible and/or visible alarm after the initiation of the operating cycle if the leak test connectors were not
connected to the endoscopes.
4.2.6 WDs with an automatic leak test shall be tested in accordance with 6.5.
ISO 15883-4:2008(E)
4.3 Cleaning
4.3.1 General
All surfaces (internal and external) of the endoscope(s) which are required to be disinfected by the WD shall
be cleaned. (See ISO 15883-1:2006, 4.2.1.1, 5.1.10 and 6.10.2).
NOTE Some endoscope(s) have component parts (e.g. electronic connectors) which their manufacturer recommends
should not be immersed in water or aqueous solutions. These component parts will be processed in accordance with the
manufacturer’s instructions and then protected from immersion during processing in the WD (see 5.1.2).
Cleaning shall comprise washing with a detergent solution which may, when necessary, be preceded by
flushing. Washing shall be followed by rinsing unless the conditions specified in 4.3.4 have been met.
4.3.2 Flushing
When necessary, the WD shall provide means to flush the internal and external surfaces of the endoscope.
NOTE Flushing before washing might be necessary to eliminate soils or to avoid any interaction between the
chemicals used during pre-treatment and those of the WD processing cycle.
The flushing water or solution shall be discharged during or after each process cycle and shall not be re-used.
4.3.3 Washing
The WD manufacturer shall specify the detergent(s) to be used, as established during type testing [see 8 m)].
The detergent solution shall be discharged during or after each process cycle and shall not be re-used.
The temperature of the detergent solution throughout the washing stage shall be monitored to ensure that it
remains within the limits specified by the manufacturer of the detergent and be compatible with the
temperature limits for the device(s) to be processed.
This shall be achieved either
a) by controlling the temperature of the detergent solution
or
b) where appropriate, by operating the WD at ambient temperature with a means of preventing operation of
the WD when the detergent temperature is outside the specified temperature range.
4.3.4 Post-washing rinsing
Rinsing between washing and disinfection shall be used to reduce the concentration of residues (process
chemicals and soiling including microbial contamination) to a level established as not exceeding that which
would impair the efficacy of the disinfection process.
Rinsing shall take place between washing and disinfection unless it can be demonstrated that:
a) there is no reaction between incompatible process chemicals being used for each of these phases;
b) there is no adverse reaction between suspended or residual soiling and the disinfectant.
The interaction between the disinfectant and residual soiling shall be tested under conditions in which soiling
is at or above the maximum level that may occur in use and the disinfectant is at or below the minimum
specified in-use concentration.
The rinse water quality shall be specified by the WD manufacturer; this shall be of, at least, potable quality.
6 © ISO 2008 – All rights reserved

ISO 15883-4:2008(E)
4.3.5 Determination of cleaning efficacy
Cleaning efficacy shall be determined in accordance with 6.11.
4.4 Disinfecting
4.4.1 General
National regulatory requirements may specify approval procedures for disinfectants to be used in WDs for
medical devices. Compliance with these national requirements shall be deemed to meet the requirements of
4.4 within the territory where these requirements apply.
The capability of the WD to provide disinfection of the device shall be deemed to have been established if,
when the WD is tested as specified in 6.12.6 under the specified conditions of disinfectant concentration,
volume, temperature and contact time the required microbial inactivation factor is attained (see 4.4.2.4).
The choice of disinfectant shall ensure that the spectrum of activity is appropriate for the intended use. The
efficacy of disinfectants may be seriously impaired by residual soiling, inorganic salts etc. remaining on the
device(s) and therefore an effective cleaning prior to disinfection is required.
NOTE Other process chemicals, e.g. detergents can react with and seriously impair the activity of disinfectants if they
are not removed before the disinfection stage.
4.4.2 Efficacy of the disinfectant
4.4.2.1 The following tests are based on the use of aqueous solutions of a disinfectant. Other systems
based on gaseous disinfectants are not excluded; equivalent tests are required.
4.4.2.2 When tested in accordance with 6.12.2, the in vitro efficacy of the disinfectant shall be
demonstrated.
4.4.2.3 A specific neutralization method for the disinfectant shall be validated in accordance with 6.12.2.6.
NOTE These data can be provided by the disinfectant manufacturer.
4.4.2.4 When tested in accordance with 6.12.2 and 6.12.6 for the minimum exposure time at the
minimum concentration and the minimum temperature to be used in the WD the disinfectant shall
demonstrate:
a) at least a log 6 inactivation of vegetative bacteria including yeasts and yeast-like fungi;
b) at least a log 5 inactivation of mycobacteria;
c) at least a log 4 inactivation of fungal spores and viruses.
NOTE 1 The inactivation values specified are regarded as the minimum necessary for endoscopes; they may be
different from the values specified in other standards to permit a label claim for biocidal activity.
NOTE 2 National regulatory authorities can require higher inactivation values.
4.4.2.5 The disinfectant chosen shall also be active against bacterial endospores.
When tested at the minimum concentration and the minimum temperature to be used in the WD when
processing endoscopes, the disinfectant should reduce the population of bacterial spores by not less than
log 6 within 5 h of exposure, or at an equivalent rate. The disinfectant should be tested against spores of
known high resistance to the disinfectant from both aerobic and anaerobic organisms.
ISO 15883-4:2008(E)
4.4.2.6 The experimental conditions of tests intended to demonstrate the microbicidal activity of the
disinfectant in vitro shall consider the conditions of use of the disinfectant. Thus, when there is no rinsing
between cleaning and disinfection, the disinfectant shall be tested in the presence of interfering substances
(see also 4.3.4), and, for example, dirty conditions.
NOTE Demonstration by the disinfectant manufacturer that the disinfectant meets the above requirements may be
made employing methods based on relevant published standards or other relevant publications (e.g. EN 13624, EN 13727,
EN 14348, EN 14476, EN 14561, EN 14562, AOAC sporicidal test, ASTM E2111-00).
4.4.3 Temperature
The temperature of the disinfectant solution throughout the disinfection stage shall be monitored to ensure
that it remains within the limits specified by the manufacturer of the disinfectant and be compatible with the
temperature limits for the device(s) to be processed.
This shall be achieved either by controlling the temperature of the disinfectant solution or, where appropriate,
by operating the WD at ambient temperature with means to prevent operation of the WD when the disinfectant
temperature is outside the specified temperature range.
4.4.4 Process monitoring
The process monitoring of each operating cycle by the automatic controller shall include verification that the
process conditions specified by the WD manufacturer as necessary and sufficient for disinfection to take place
(e.g. disinfectant concentration, temperature and contact time) were attained (see also 5.5).
Microbial testing (e.g. with biological indicators or inoculated carriers) of the disinfection stage on each cycle
shall not be used to meet this requirement.
NOTE Confirmation of the concentration of disinfectant can require e.g. measurement of the volume of disinfectant
and water admitted together with a certificate of conformity from the disinfectant supplier for the concentration of the
disin
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