prEN ISO 11140-4

SLOVENSKI STANDARD
01-september-2025
Sterilizacija izdelkov za zdravstveno nego - Kemijski indikatorji - 4. del: Sistemi
indikatorjev tipa 2, ki se uporabljajo namesto Bowie-Dickovega preskusa za
ugotavljanje prodiranja pare (ISO/DIS 11140-4:2025)
Sterilization of health care products - Chemical indicators - Part 4: Type 2 indicator
systems as an alternative to the Bowie and Dick-type test for the detection of steam
penetration (ISO/DIS 11140-4:2025)
Sterilisation von Produkten für die Gesundheitsfürsorge - Chemische Indikatoren - Teil 4:
Indikatoren der Klasse 2, die alternativ zum Bowie-Dick-Test für den Nachweis der
Dampfdurchdringung verwendet werden (ISO/DIS 11140-4:2025)
Stérilisation des produits de santé - Indicateurs chimiques - Partie 4: Systèmes
d'indicateurs de Type 2 comme alternative à l'essai de Bowie et Dick pour la détection
de la pénétration de la vapeur (ISO/DIS 11140-4:2025)
Ta slovenski standard je istoveten z: prEN ISO 11140-4
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.

DRAFT
International
Standard
ISO/DIS 11140-4
ISO/TC 198
Sterilization of health care
Secretariat: ANSI
products — Chemical indicators —
Voting begins on:
Part 4: 2025-07-30
Type 2 indicator systems as an
Voting terminates on:
2025-10-22
alternative to the Bowie and Dick-
type test for the detection of steam
penetration
Stérilisation des produits de santé — Indicateurs chimiques —
Partie 4: Systèmes d'indicateurs de Type 2 comme alternative à
l'essai de Bowie et Dick pour la détection de la pénétration de la
vapeur
ICS: 11.080.20
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document is circulated as received from the committee secretariat.
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Reference number
ISO/DIS 11140-4:2025(en)
DRAFT
ISO/DIS 11140-4:2025(en)
International
Standard
ISO/DIS 11140-4
ISO/TC 198
Sterilization of health care
Secretariat: ANSI
products — Chemical indicators —
Voting begins on:
Part 4:
Type 2 indicator systems as an
Voting terminates on:
alternative to the Bowie and Dick-
type test for the detection of steam
penetration
Stérilisation des produits de santé — Indicateurs chimiques —
Partie 4: Systèmes d'indicateurs de Type 2 comme alternative à
l'essai de Bowie et Dick pour la détection de la pénétration de la
vapeur
ICS: 11.080.20
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document is circulated as received from the committee secretariat.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
© ISO 2025
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
STANDARDS MAY ON OCCASION HAVE TO
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Published in Switzerland Reference number
ISO/DIS 11140-4:2025(en)
ii
ISO/DIS 11140-4:2025(en)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 General . 3
5 Requirements . 3
6 Indicator format . 4
7 Performance requirements . . 5
8 Packaging and labelling . 6
Annex A (normative) Standard test cycles . 9
Annex B (normative) Estimation of visual difference between colour of the substrate and of the
changed or unchanged indicator system by determination of relative reflectance density . 14
Annex C (normative) Determination of uniform colour change on exposure to saturated steam .18
Annex D (normative) Determination of equivalence of the alternative indicator to the Bowie
and Dick test . 19
Annex E (normative) Determination of reproducibility of fail conditions created in a standard
test pack by air injection, air leak and retained air systems .21
Annex F (normative) Determination of indicator colour change on exposure to dry heat .25
Annex G (normative) Determination of shelf life of indicators .26
Annex H (normative) Steam exposure apparatus and steam for test purposes .27
Annex I (normative) Standard test pack .30
Annex J (normative) Air injection system . .31
Annex K (informative) Relationship between chemical indicator components .33
Annex ZA (informative) Relationship between this European Standard and the General Safety
and Performance Requirements of Regulation (EU) 2017/745 aimed to be covered .34
Bibliography .37

iii
ISO/DIS 11140-4:2025(en)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee
has been established has the right to be represented on that committee. International organizations,
governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely
with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent
rights identified during the development of the document will be in the Introduction and/or on the ISO list of
patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 198, Sterilization of health care products
This third edition cancels and replaces the second edition (ISO 11140-4:2007), which has been technically
revised.
The main changes are as follows:
— change of title from class 2 indicator to type 2 indicator to align with ISO 11140-1;
— correct use of the defined terms indicator and indicator system to align with ISO 11140-1;
— updated normative references;
— inserted common Clause 4 for ISO/TC 198 documents, replacing Clause 8;
— added Annex M, modified from ISO 11140-1.
A list of all parts in the ISO 11140 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.

iv
ISO/DIS 11140-4:2025(en)
Introduction
[1]
The Bowie and Dick test is a test for steam sterilizers for products to be sterilized that are within sterile
barrier systems or other porous loads. As such it is performed during the demonstration of conformance of
steam sterilizers to EN 285 and as a routine test of performance in ISO 17665. The test method is described
in EN 285.
A failure of the Bowie and Dick test is symptomatic of a number of potential problems with the sterilizer that
could compromise the uniform sterilization of a load to be processed. This failure is not conclusive proof
that the fault in the sterilizer is due to air retention, air leakage or non-condensable gases, and it can be
necessary to investigate other causes of failure.
The Bowie and Dick test was conceived as a test for successful air removal from high-vacuum porous-load
[1]
sterilizers used in the sterilization of health care products . A successful Bowie and Dick test indicates
sufficient air removal to facilitate rapid and even penetration of steam into the test load. The presence of air
within the pack, due to an inefficient air removal stage, an air leak during this stage or non-condensable gases
in the steam supply, are circumstances which can lead to failure of the test. The result of the test can also
be affected by other factors which inhibit steam penetration into the test load. The test does not necessarily
demonstrate either achievement of the required temperature or maintenance of that temperature for the
required time to achieve sterilization.
The Bowie and Dick test consists of two components:
a) a small standardized test load;
b) a chemical indicator to detect the presence of steam.
[1]
The Bowie and Dick test as originally described utilized huckaback towels as the material for the test
load. The test as described in EN 285 uses cotton sheets for this purpose.
Indicators intended as an alternative to the Bowie and Dick test use different materials for the test load and
employ indicators specifically formulated for use with the defined test load. Because a range of different
tests in different countries have historica
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