SIST EN ISO 11140-4:2007

SLOVENSKI STANDARD
01-september-2007
1DGRPHãþD
SIST EN 867-4:2001
Sterilizacija izdelkov za zdravstveno nego – Kemijski indikatorji – 4. del: Indikatorji
razreda 2, ki se uporabljajo namesto Bowie-Dickovega preskusa za ugotavljanje
prodiranja pare (ISO 11140-4:2007)
Sterilization of health care products - Chemical indicators - Part 4: Class 2 indicators as
an alternative to the Bowie and Dick-type test for detection of steam penetration (ISO
11140-4:2007)
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 11140-4:2007)
Stérilisation des produits de santé - Indicateurs chimiques - Partie 4: Indicateurs de
classe 2 comme alternative a l'essai de Bowie et Dick pour la détection de la pénétration
de la vapeur (ISO 11140-4:2007)
Ta slovenski standard je istoveten z: EN ISO 11140-4:2007
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 11140-4
NORME EUROPÉENNE
EUROPÄISCHE NORM
March 2007
ICS 11.080.01 Supersedes EN 867-4:2000
English Version
Sterilization of health care products - Chemical indicators - Part
4: Class 2 indicators as an alternative to the Bowie and Dick-
type test for detection of steam penetration (ISO 11140-4:2007)
Stérilisation des produits de santé - Indicateurs chimiques - Sterilisation von Produkten für die Gesundheitsfürsorge -
Partie 4: Indicateurs de Classe 2 comme alternative à Chemische Indikatoren - Teil 4: Indikatoren der Klasse 2,
l'essai de Bowie et Dick pour la détection de la pénétration die alternativ zum Bowie-Dick-Test für den Nachweis der
de la vapeur (ISO 11140-4:2007) Dampfdurchdringung verwendet werden (ISO 11140-
4:2007)
This European Standard was approved by CEN on 14 March 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 11140-4:2007: E
worldwide for CEN national Members.

Foreword
This document (EN ISO 11140-4:2007) has been prepared by Technical Committee ISO/TC
198 "Sterilization of health care products" in collaboration with 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 September 2007, and conflicting
national standards shall be withdrawn at the latest by September 2007.

This document supersedes EN 867-4:2000.

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).
The series EN ISO 11140 consists of the following parts under the general title Sterilization of
health care products - Chemical indicators:

 Part 1: General requirements
 Part 3: Class 2 indicator systems for use in the Bowie and Dick-type steam penetration
test
 Part 4: Class 2 indicators as an alternative to the Bowie and Dick-type test for detection of
steam penetration
Attention is drawn to the fact that the series ISO 11140 additionally consists of Part 5: Class 2
indicators for Bowie and Dick-type air removal tests. However, this Part of ISO 11140 will not
be part of the series EN ISO 11140 because CEN/TC 102 decided not to adopt ISO 11140-5
as a European Standard.
In addition, reference is made to EN 867-5 Non-biological systems for use in sterilizers -
Part 5: Specification for indicator systems and process challenge devices for use in
performance testing for small sterilizers type B and type S and to EN ISO 15882 Sterilization
of health care products - Chemical indicators - Guidance for selection, use and interpretation
of results: Both standards are currently being revised under the Vienna Agreement
(ISO/TC 198 lead).
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.
Endorsement notice
The text of ISO 11140-4:2007 has been approved by CEN as EN ISO 11140-4:2007 without
any modifications.
INTERNATIONAL ISO
STANDARD 11140-4
Second edition
2007-03-15
Sterilization of health care products —
Chemical indicators —
Part 4:
Class 2 indicators as an alternative to the
Bowie and Dick-type test for detection of
steam penetration
Stérilisation des produits de santé — Indicateurs chimiques —
Partie 4: Indicateurs de Classe 2 comme alternative à l'essai de Bowie
et Dick pour la détection de la pénétration de la vapeur

Reference number
ISO 11140-4:2007(E)
©
ISO 2007
ISO 11140-4:2007(E)
PDF disclaimer
This PDF file may contain embedded typefaces. In accordance with Adobe's licensing policy, this file may be printed or viewed but
shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing. In
downloading this file, parties accept therein the responsibility of not infringing Adobe's licensing policy. The ISO Central Secretariat
accepts no liability in this area.
Adobe is a trademark of Adobe Systems Incorporated.
Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation
parameters were optimized for printing. Every care has been taken to ensure that the file is suitable for use by ISO member bodies. In
the unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below.

©  ISO 2007
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or
ISO's member body in the country of the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Published in Switzerland
ii © ISO 2007 – All rights reserved

ISO 11140-4:2007(E)
Contents Page
Foreword. iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions. 2
4 General requirements. 3
5 Indicator system format . 4
6 Performance requirements . 4
7 Packaging and labelling. 6
8 Quality assurance. 7
Annex A (normative) Determination of indicator strength during and after steam sterilization . 8
Annex B (normative) Standard test cycles. 10
Annex C (normative) Estimation of visual difference between colour of the substrate and of the
changed or unchanged indicator system by determination of relative reflectance density . 15
Annex D (normative) Determination of uniform colour change on exposure to saturated steam . 19
Annex E (normative) Determination of equivalence of the alternative indicator to the Bowie and
Dick test . 20
Annex F (normative) Determination of reproducibility of fail conditions created in a standard test
pack by air injection, air leak and retained air systems . 22
Annex G (normative) Determination of indicator colour change on exposure to dry heat . 26
Annex H (normative) Determination of shelf life of product. 27
Annex I (normative) Accelerated ageing of test samples . 28
Annex J (normative) Steam exposure apparatus and steam for test purposes. 29
Annex K (normative) Standard test pack. 32
Annex L (normative) Air injection system . 33
Bibliography . 35

ISO 11140-4:2007(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 11140-4 was prepared by Technical Committee ISO/TC 198, Sterilization of health care products.
This second edition cancels and replaces the first edition (ISO 11140-4:2001) which has been technically
revised.
ISO 11140 consists of the following parts, under the general title Sterilization of health care products —
Chemical indicators:
⎯ Part 1: General requirements
⎯ Part 3: Class 2 indicator systems for use in the Bowie and Dick-type steam penetration test
⎯ Part 4: Class 2 indicators as an alternative to the Bowie and Dick-type test for detection of steam
penetration
⎯ Part 5: Class 2 indicators for Bowie and Dick-type air removal tests
iv © ISO 2007 – All rights reserved

ISO 11140-4:2007(E)
Introduction
The Bowie and Dick test is a performance test for steam sterilizers for wrapped goods and 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 17665-1. 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 rapid
and even penetration of steam into the test pack. 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 may also be affected by other factors which inhibit
steam penetration. The test does not necessarily demonstrate either achievement of the required temperature
or maintenance of that temperature for the required time to achieve sterilization.
A test pack for the Bowie and Dick test consists of two components:
a) a small standardized test load;
b) a chemical indicator system 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 indicator systems specifically formulated for use with the defined test load. Because a range of
different tests in different countries have historically been termed the Bowie and Dick test, the term “Bowie
and Dick-type test” is used in this part of ISO 11140.
This part of ISO 11140 specifies the performance of the indicator system in combination with the test load with
which it is intended to be used. The test load may be presented with the indicator system already incorporated
and intended for single use, or it may be intended for multiple use with a new indicator system to be inserted
prior to each use.
The indicator for which the performance is specified in this part of ISO 11140 is intended to indicate when
steam penetration has been inadequate. The performance of the indicator specified in this part of ISO 11140
should be equivalent, but not necessarily identical, to the performance obtained in the Bowie and Dick-type
test as described in ISO 11140-3. Equivalence should be regarded as providing a similar response to steam
penetration with any differences being predictable and such that the necessary level of assurance of
satisfactory steam penetration is provided. An indicator meeting this specification is not intended to identify
which of the potential causes of poor steam penetration was responsible for the failure indicated by the test.
INTERNATIONAL STANDARD ISO 11140-4:2007(E)

Sterilization of health care products — Chemical indicators —
Part 4:
Class 2 indicators as an alternative to the Bowie and Dick-type
test for detection of steam penetration
1 Scope
This part of ISO 11140 specifies the performance for a Class 2 indicator to be used as an alternative to the
Bowie and Dick-type test for steam sterilizers for wrapped health care goods (instruments, etc., and porous
loads).
NOTE The Bowie and Dick-type test is used for routine testing of steam sterilizers and validation of steam
sterilization processes.
An indicator complying with this part of ISO 11140 incorporates a specified material which is used as a test
load. This test load may, or may not, be re-usable. This part of ISO 11140 does not specify requirements for
the test load, but specifies the performance of the indicator in combination with the test load with which it is
intended to be used. The indicator specified in this part of ISO 11140 is intended to identify poor steam
penetration but does not necessarily indicate the cause of this poor steam penetration.
This part of ISO 11140 does not include test methods to establish the suitability of these indicator systems for
use in sterilizers in which the air removal stage does not include evacuation below atmospheric pressure.
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 5-1, Photography — Density measurements — Part 1: Terms, symbols and notations
ISO 5-3, Photography — Density measurements — Part 3: Spectral conditions
ISO 5-4:1995, Photography — Density measurements — Part 4: Geometric conditions for reflection density
ISO 187:1990, Paper, board and pulps — Standard atmosphere for conditioning and testing and procedure for
monitoring the atmosphere and conditioning of samples
ISO 2248, Packaging — Complete, filled transport packages — Vertical impact test by dropping
ISO 10012-1, Quality assurance requirements for measuring equipment — Part 1: Metrological confirmation
system for measuring equipment
ISO 11140-1:2005, Sterilization of health care products — Chemical indicators — Part 1: General
requirements
ISO/CIE 10526:1999, CIE standard illuminants for colorimetry
ISO 11140-4:2007(E)
IEC 60584-2:1982, Thermocouples. Part 2: Tolerances
IEC 60584-2/am1:1989, Amendment 1 — Thermocouples. Part 2: Tolerances
IEC 60751:1983, Industrial platinum resistance thermometer sensors
IEC 60751/am1:1986, Amendment 1 — Industrial platinum resistance thermometer sensors
EN 285:2006, Sterilization — Steam sterilizers — Large sterilizers
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 11140-1 and the following apply.
3.1
air pocket
concentration of residual, induced or injected air or non-condensable gases in the standard test pack
3.2
chamber reference temperature
temperature measured at a defined reference point within the steam exposure apparatus
NOTE The defined reference point is usually located in the chamber drain or active chamber discharge.
3.3
exposure time
period for which the chamber reference temperature lies within the sterilization temperature band
3.4
pre-assembled pack
indicator in which the indicator system is incorporated into the test load during the manufacturing process and
which is supplied ready for use
3.5
reference fault period
period of 30 s commencing when the chamber reference temperature attains the set operating temperature
3.6
sterilization temperature
minimum temperature of the sterilization temperature band
NOTE The use of the word “sterilization” within this and other definitions is not intended to imply that sterilizing
conditions will take place under the test cycle conditions.
3.7
sterilization temperature band
range of temperatures from the sterilization temperature to the maximum allowable temperature which may
prevail throughout the load during the holding time
NOTE These temperatures are usually stated in whole degrees centigrade.
3.8
temperature depression
thermodynamic temperature difference in kelvin given by (chamber reference temperature, in degrees
centigrade) minus (temperature in the standard test pack, in degrees centigrade)
2 © ISO 2007 – All rights reserved

ISO 11140-4:2007(E)
3.9
test equilibration time
time elapsed after the chamber reference temperature attains the set operating temperature until the
temperature within the standard test pack is the same as the chamber reference temperature, within the limits
of accuracy of the temperature-measuring equipment
3.10
user-assembled pack
indicator in which the user combines the indicator system with the test load prior to use
4 General requirements
4.1 The requirements of ISO 11140-1 apply.
4.2 Test samples shall be conditioned in accordance with ISO 187 prior to testing for performance.
4.3 Compliance with the requirements of this part of ISO 11140 shall be determined by establishing
conformity with the performance requirements of Clause 6.
4.4 The indicator shall have sufficient strength to withstand steam sterilization and subsequent handling.
Compliance shall be tested in accordance with Annex A.
4.5 Test cycles for demonstrating compliance with the requirements of this part of ISO 11140 shall employ
sub-atmospheric, trans-atmospheric and super-atmospheric air removal stages (see Table 1 and B.1, B.2 and
B.3) except when the indicator, or indicator system, is intended solely for use with one type of air removal
system, in which case only the specified air removal system needs to be used during compliance testing.
4.6 A thermometric recording instrument(s) shall be used in conjunction with temperature sensors to record
the temperatures measured in the locations specified in the tests described in this part of ISO 11140. The
temperature-measuring equipment used in all test methods for demonstrating compliance with this part of
ISO 11140 shall meet the following requirements.
a) Temperature sensors shall be either platinum resistance and comply with Class A of IEC 60751:1983 and
IEC 60751 Amendment 1:1986 or a thermocouple and comply with one of the tables of tolerance class 1
of IEC 60584-2:1982 and IEC 60584-2 Amendment 1:1989.
b) The performance characteristic of the temperature sensor shall not be affected by the environment in
which it is used, e.g. pressure, steam or vacuum.
c) The temperature sensors shall have a response time in water of τ u 0,5 s.
d) The temperature measured by all temperature sensors when immersed in a temperature source at a
temperature known to within ± 0,1 K, and within the sterilization temperature band, shall not differ by
more than 0,5 K.
e) The recording instrument shall record the temperature from a minimum of 6 sensors. The sampling
interval shall not exceed 2,5 s. All data sampled shall be used for the interpretation of results.
f) The scale range shall include 0 °C to 150 °C. For analogue instruments, the minor mark interval shall not
exceed 1 K, the resolution shall be not less than 0,5 K and the chart speed shall be not less than
15 mm/min. Digital instruments shall register and record in increments of not more than 0,1 K.
g) The limit of error of the recording instrument between 0 °C and 150 °C (excluding temperature sensors)
shall not exceed 0,25 % when tested in an ambient temperature of (20 ± 3) °C. The additional error due
to change in the environmental temperature shall not exceed 0,04 K/K.
h) Calibration shall be carried out using a working or reference standard that is traceable to a national
standard or a primary standard. The instrument shall have a valid test certificate.
ISO 11140-4:2007(E)
5 Indicator system format
5.1 When the indicator system is one in which the indicator reagent is distributed on a substrate, it shall
meet the following requirements.
a) The indicator reagent shall be distributed to cover not less than 30 % of the surface area of the substrate.
The distance between adjacent areas of indicator reagent shall not exceed 20 mm.
The pattern of indicator reagent distribution should permit clear interpretation of the colour change.
b) The substrate shall have a colour which is uniform to visual observation.
c) The indicator system shall have a difference in relative reflectance density of not less than 0,3 between
the colour of the substrate and either the changed indicator or unchanged indicator as specified by the
manufacturer.
Compliance shall be tested in accordance with Annex C.
5.2 When the indicator system depends on migration of the indicator reagent to demonstrate change, the
pattern of indicator reagent distribution before and after use shall permit clear interpretation of the result.
5.3 When the indicator system is intended for use with a user-assembled pack, the indicator system shall
permit writing in permanent ink to be made legibly on both processed and unprocessed materials. Those
markings made before processing shall remain legible after processing.
5.4 When the indicator system is provided by the manufacturer already incorporated into the test load, the
material of either the indicator or the indicator system, as appropriate, shall permit writing to be made after
processing.
6 Performance requirements
6.1 The indicator, when tested in combination with the test load specified by the manufacturer, shall show a
uniform colour change complying with 5.1 c) after exposure to saturated steam at 134 °C for 3,5 min, or at
121 °C for 15 min or at any other time/temperature combination specified by the manufacturer when the
+1,5
⎛⎞
temperature tolerance shall be °C and the time tolerance shall be ± 5 s.
⎜⎟
⎝⎠
Compliance shall be tested in accordance with Annex D using the steam exposure apparatus. The steam
exposure apparatus shall be operated with the standard test cycles described in Annex B as shown in Table 1.
Indicators intended for use only with specific air removal cycles shall be tested with those specific cycles only
(see 5.7 of ISO 11140-1:2005).
Indicators intended to be used over a wide range of sterilization temperatures, e.g. both for cycles operating at
121 °C and for those operating at 134 °C, may not give the same depth or intensity of colour change at both
temperatures. This should be regarded as in compliance if:
a) all other performance characteristics required by this part of ISO 11140 are met;
b) the nature of the colour change is unambiguously defined in the instructions for use (see 5.8 of
ISO 11140-1:2005).
6.2 The indicator shall show no colour change, incomplete colour change, or uneven colour change when
exposed to a test cycle previously demonstrated to produce a reference fault condition (a fault response).
Exposure to a reference fault condition shall produce a fault response regardless of the means of creating the
reference fault condition, i.e. the system used to produce the fault may use air retention, air leak or air
injection. The test cycles used to generate the reference fault conditions shall be as shown in Table 1. The
4 © ISO 2007 – All rights reserved

ISO 11140-4:2007(E)
chamber reference temperatures and holding times shall include 134 °C for 3,5 min, or 121 °C for 15 min or
another time/temperature combination specified by the manufacturer (see 6.1) when the temperature
⎛⎞+1,5
tolerance shall be °C and the time tolerance shall be ± 5 s.
⎜⎟
⎝⎠
Compliance shall be tested in accordance with Annex E.
Compliance with the fault condition reproducibility shall be demonstrated in accordance with Annex F.
Table 1 — Schedule of test cycles to be used
Standard test cycle of Annex B
B.1 B.2 B.3
Test condition
Sub-atmospheric Trans-atmospheric Super-atmospheric
pulsing pulsing pulsing
“Pass” cycle (see 6.1) √ √ √
“Fail” cycle – modified air removal stage (see 6.2) √ √ x
“Fail” cycle – induced leak (see 6.2) √ x x
“Fail” cycle – air injection (see 6.2) √ x √
√ = test required;
x = test not required.
6.3 The indicator system shall show no discernible colour change after exposure to dry heat at (140 ± 2) °C
for not less than 30 min.
With some indicators, the indicator system can show a slight colour change after exposure to dry heat; this
shall be acceptable if the change that occurs is slight or markedly different from that brought about by
exposure to steam in accordance with 6.1 and within the limits specified by the manufacturer.
Compliance shall be tested in accordance with Annex G.
6.4 Indicators intended for use only with a sterilization temperature of 121 °C shall be tested by exposure to
dry heat at (130 ± 2) °C for not less than 45 min if the indicator will not withstand heating to 140 °C.
Compliance shall be tested in accordance with Annex G.
6.5 Indicator systems intended for use with re-usable user-assembled packs shall not visibly transfer
indicator reagent to the material of the test load during processing. Pre-assembled packs and indicator
systems intended for use with single-use user-assembled packs shall not transfer indicator reagent to the
material of the test load during processing to an extent which impairs the utility of the product.
Compliance shall be demonstrated by visual examination after testing in accordance with the requirements of
6.1 and Annex D.
6.6 The indicator shall comply with the requirements of this part of ISO 11140 for the duration of the shelf
life specified by the manufacturer.
If any change in the indicator occurs during ageing, it shall be different from the change on exposure to
saturated steam (as described in 6.1) and shall either inactivate the indicator system so that no further change
can take place or not affect the performance of the indicator system with respect to the requirements of 6.1
and 6.2.
Compliance shall be tested in accordance with Annex H or by performance testing after accelerated ageing in
accordance with Annex I.
ISO 11140-4:2007(E)
7 Packaging and labelling
7.1 Each indicator, or indicator system, shall be marked with:
a) the sterilization temperature(s) at which the product is designed to be used;
b) a unique code from which the manufacturing history can be traced;
c) the expiry date under the specified storage conditions;
d) at least the information summarized in Figure 1.
Adjacent to each heading there shall be a clear space not less than 5 mm × 20 mm for the user to enter the
required information at the time of use or, if the size of the indicator system does not permit this, each
indicator or indicator system shall be supplied with a means of retaining the indicator or indicator system as a
permanent record which shall be printed with the information given in Figure 1. The means of retention shall
permit writing in permanent ink to be made in association with the indicator.
Cycle No. Site
Machine No. Department
Date Operator
Supervisor Result
NOTE This is an example of a suitable format. Other formats and/or text can be used.
Figure 1 — Provision for recording information to be provided on or with each indicator
7.2 When the indicator is supplied assembled, i.e. with the indicator system within the test load, the exterior
of the test load shall be marked with the sterilization temperature(s) at which the product is suitable for use,
the manufacturer's name, batch number and date of manufacture. In addition, either a means of uniquely
identifying the individual indicator or an area on the outside of the test load on to which the operator can write
the number of the machine tested and date shall be provided.
When a manufacturer provides similar products which are intended only for specific sterilization cycles, the
product shall include identification sufficient to enable the user to determine, from the instructions for use, any
restrictions on the use of the product. The identification shall be on the indicator or indicator system and, if not
visible to the user before use, shall also be on the outside of the test load.
6 © ISO 2007 – All rights reserved

ISO 11140-4:2007(E)
7.3 The transport package shall be such that the product can be removed easily. The package shall protect
the product to the extent necessary to ensure that the indicator retains its performance throughout the stated
shelf life when stored and transported in accordance with the manufacturer's instructions.
The manufacturer shall retain documentary evidence demonstrating compliance.
7.4 The outside of each package shall be marked with the sterilization temperature(s) at which the product
is suitable for use.
7.5 The information supplied by the manufacturer (see 5.8 of ISO 11140-1:2005) shall include sufficient
instructions on the use of the indicator to enable correct interpretation of the test results.
7.6 When requested by the purchaser, the manufacturer shall supply a certificate of conformity to the
requirements of this part of ISO 11140 for each batch of product supplied.
8 Quality assurance
8.1 The quality system shall ensure that the performance requirements given in Clause 6 are maintained.
8.2 Suitable records shall be maintained to ensure that, if necessary, faulty batches can be recalled from
use.
8.3 The manufacturing and distribution records shall be retained for a period of five years, or twice the
declared shelf life of the product, whichever is greater. An example of the requirements for maintaining
[6]
records is given in ISO 9001:2000 .
ISO 11140-4:2007(E)
Annex A
(normative)
Determination of indicator strength during and after steam sterilization
A.1 Apparatus
A.1.1 Steam exposure apparatus, as specified in Annex J.
A.2 Procedure
A.2.1 Expose the indicator to three successive test cycles at the stated sterilization temperature of the
indicator or indicator system. The indicator shall be tested using both the standard test cycles specified in B.1
and B.2 (see 4.5) unless the indicator is intended for use with only one type of air removal stage, in which
case the appropriate test cycle shall be used. The rate of pressure change of evacuation during the air
−1
removal pulse and during the drying stage shall be not less than 400 kPa min .
The rate of pressure change shall be determined as follows (see Figure A.1):
p=+0,125 7pp (A.1)
( )
p=+0,5pp (A.2)
( )
p − p
()
∆p
= (A.3)
∆−tt t
()
where
p is the maximum absolute pressure attained during the last air removal pulse and during the
operating stage, in kilopascals;
p is the minimum absolute pressure attained during the last air removal pulse (prior to the admission
of steam to the operating pressure required for the chamber reference temperature to attain the
sterilization temperature) and the drying stage, in kilopascals;
p is the pressure calculated from Equation A.1, in kilopascals;
p is the pressure calculated from Equation A.2, in kilopascals;
t is the time at p , in minutes;
3 3
t is the time at p , in minutes;

4 4
∆p
is the rate of pressure change, in kilopascals per minute.
∆t
A.2.2 Remove the pre-assembled or user-assembled indicator from the exposure apparatus and examine
the indicator for visible damage, including, for example, opening or distortion of seals. Record the result.
8 © ISO 2007 – All rights reserved

ISO 11140-4:2007(E)
A.2.3 If the indicator has remained intact, perform a drop test in accordance with ISO 2248 from a height of
1 m onto a firm horizontal surface. Record the result.
NOTE Concrete or terrazzo surfaces are suitable.

Figure A.1 — Determination of the rate of pressure change
A.2.4 Carry out this test with three samples for each of three separate production batches. All nine samples
can be processed simultaneously.
A.2.5 Damage occurring during the drop test, which can be demonstrated as not impairing the interpretation
of the indicator in normal use shall not constitute a failure. For re-usable test loads, any damage occurring
during the drop test which can be demonstrated as not impairing the subsequent re-use of the test load shall
not constitute a failure.
ISO 11140-4:2007(E)
Annex B
(normative)
Standard test cycles
B.1 Cycle 1: Air removal by sub-atmospheric pulsing
The standard test cycle for sub-atmospheric air removal shall consist of the following steps:
a) evacuation of the chamber to 5,0 kPa;
b) steam admission to 97,0 kPa;
c) repetition of steps a) and b) a further three times;
d) if air injection is being used, it shall take place and be completed during steam admission to the exposure
time at a pressure of between 75 kPa and 105 kPa (indicated by an arrow on Figure B.1);
e) steam admission to set operating pressure (see specific requirements for steam admission stage in B.4);
f) exposure time;
g) evacuation to 5,0 kPa;
h) air admission.
The actual pressures achieved at the set points shall be determined by the tolerance permitted for the steam
exposure apparatus (see Annex J).

Key
1 set operating pressure (kPa)
2 air injection
Figure B.1 — Standard test cycle — Sub-atmospheric air removal
10 © ISO 2007 – All rights reserved

ISO 11140-4:2007(E)
B.2 Cycle 2: Air removal by trans-atmospheric pulsing
The standard test cycle for air removal by trans-atmospheric pulsing shall consist of the following steps:
a) evacuation of the chamber to 5,0 kPa;
b) steam admission to 150 kPa;
c) evacuation of the chamber to 50 kPa;
d) repetition of steps b) and c) a further three times;
e) steam admission to set operating pressure minus 10,0 kPa;
f) evacuation of chamber to 110 kPa to 120 kPa;
g) repetition of steps e) and f) one further time;
h) steam admission to set operating pressure (see specific requirements for steam admission stage in B.4);
i) exposure time;
j) evacuation to 5,0 kPa;
k) air admission.
The actual pressures achieved at the set points shall be determined by the tolerance permitted for the steam
exposure apparatus (see Annex J).

Key
1 set operating pressure
2 set operating pressure minus 10 kPa
Figure B.2 — Standard test cycle — Trans-atmospheric air removal
ISO 11140-4:2007(E)
B.3 Cycle 3: Air removal by super-atmospheric pulsing
The standard test cycle for air removal by super-atmospheric pulsing shall consist of the following steps:
a) evacuation of the chamber to 5,0 kPa;
b) steam admission to 95 kPa;
c) evacuation of the chamber to 5,0 kPa;
d) repetition of steps b) and c);
e) steam admission to set operating pressure minus 20,0 kPa;
f) evacuation of the chamber to 105 kPa to 120 kPa;
g) repetition of steps e) and f) a further two times;
h) if air injection is being used, it shall take place during steam admission to the exposure time at a pressure
of between 120 kPa and 130 kPa (indicated in Figure B.3);
i) steam admission to set operating pressure (see specific requirements for steam admission stage in B.4);
j) exposure time;
k) evacuation to 5,0 kPa;
l) air admission.
Key
1 set operating pressure (kPa)
2 set operating pressure minus 20 kPa
3 air injection
Figure B.3 — Standard test cycle — Super-atmospheric air removal
12 © ISO 2007 – All rights reserved

ISO 11140-4:2007(E)
B.4 Acceptance limits during steam admission
B.4.1 The rate of pressure rise during steam admission, to set operating pressure over the range 100 kPa
or lowest pressure at the bottom of the last super-atmospheric pulse to the set operating pressure of the
−1 −1
exposure time, shall be between 100 kPa min and 250 kPa min as indicated in Figure B.4.
B.4.2 Select the operating temperature of the exposure time such that it corresponds to the temperature as
stated for the indicator. Set the operating pressure such that it corresponds to a saturated steam temperature
of (selected operating temperature, in degrees centigrade + 0,2 °C).
B.4.3 The integral [Integrated Come-up Exposure (ICE)] between the chamber reference temperature when
the chamber reaches 100 kPa, or at the bottom of the last super-atmospheric pulse, whichever is the greater,
and the set temperature during the steam admission period, bounded by the chamber reference temperature
on the graph, shall not exceed T × (12T /6)
R R
where T is the set temperature in degrees centigrade minus 100 °C.
R
EXAMPLES
⎛⎞12× 34
At a set temperature 134 °C the integral shall not exceed 34 × = 2 312 s⋅K or
⎜⎟
⎝⎠
⎛⎞12× 21
at a set temperature 121 °C the integral shall not exceed 21 × = 882 s⋅K.
⎜⎟
⎝⎠
NOTE 1 These limits are intended to ensure that steam admission does not contribute to excessive exposure of the
indicator to atypical conditions. ICE shall be calculated using the equation:
t
ICE=−(TT )⋅dt (B.1)
∑
1o
t
o
where
T is the chamber reference temperature at time t, in degrees centigrade;
T is 100 °C or the lowest temperature of the last positive pulse, in degrees centigrade;
o
dt is 1 s;
t is the time at which chamber reference temperature attains T , in seconds;
o o
t is the time after t at which the chamber reference temperature, T , attains set operating temperature, T ,

1 o c R
e.g. 134 °C, in seconds.
NOTE 2 Each of the test cycles described within this Annex consists of three principal stages: air removal, exposure
time (equivalent to the sterilization stage) and evacuation stage. The temperatures attained during the air removal stage
and the duration of the air removal stage can have a significant effect on indicator performance. The cycles described are
not intended to imitate any of the many cycles which are commercially available. They are intended to provide an overall
range of effects within which most commercially available cycles will occur.
ISO 11140-4:2007(E)
Key
()pp−
Ro
1 maximum rate of pressure rise during steam admission
t
1min
2 rate of pressure rise
()pp−
Ro
3 minimum rate of pressure rise during steam admission
t
1max
4 Integrated Come-up Exposure: area bounded by T and the curve traced by T over the time t to t
o c o 1
−1
t is the come-up time at the minimum allowed rate of pressure rise of 100 kPa min
1max
−1
t is the come-up time at the maximum allowed rate of pressure rise of 250 kPa min

1min
p is the pressure of saturated steam, corresponding to the set operating temperature, in kilopascals
R
p is the pressure of saturated steam, corresponding to the temperature T , in kilopascals
o o
T is 1
...