SIST EN ISO 11140-3:2007
Sterilization of health care products - Chemical indicators - Part 3: Class 2 indicator systems for use in the Bowie and Dick-type steam penetration test (ISO 11140-3:2007)
Sterilization of health care products - Chemical indicators - Part 3: Class 2 indicator systems for use in the Bowie and Dick-type steam penetration test (ISO 11140-3:2007)
This part of ISO 11140 specifies the requirements for chemical indicators to be used in the steam penetration test for steam sterilizers for wrapped goods, e.g. instruments and porous materials. The indicator for this purpose is a Class 2 indicator as described in ISO 11140-1. Indicators complying with this part of ISO 11140 are intended for use in combination with the standard test pack as described in EN 285. This part of ISO 11140 does not consider the performance of the standard test pack, but does specify the performance of the indicator systems.
Sterilisation von Produkten für die Gesundheitsfürsorge - Chemische Indikatoren - Teil 3: Indikatorsysteme der Klasse 2 zur Verwendung im Bowie-Dick-Dampfdurchdringungstest (ISO 11140-3:2007)
Dieser Teil von ISO 11140 legt die Anforderungen an chemische Indikatoren fest, die beim Dampfdurchdringungsversuch für Dampfsterilisatoren für verpacktes Sterilisiergut, z. B. Instrumente und poröse Materialien, verwendet werden sollen. Der Indikator für diesen Zweck ist ein Indikator der Klasse 2, wie er in ISO 11140 1 beschrieben wird.
Diesem Teil von ISO 11140 entsprechende Indikatoren sind zur Verwendung in Kombination mit dem Norm-Prüfpaket, wie es in EN 285 beschrieben ist, vorgesehen. Dieser Teil von ISO 11140 berücksichtigt nicht die Leistungsfähigkeit des Norm-Prüfpakets, sondern legt die Leistungsfähigkeit der Indikatoren fest.
Stérilisation des produits de santé - Indicateurs chimiques - Partie 3: Systemes d'indicateurs de classe 2 pour utilisation lors de l'essai de Bowie et Dick de pénétration de la vapeur (ISO 11140-3:2007)
La présente partie de l’ISO 11140 spécifie les exigences relatives aux indicateurs chimiques destinés à être utilisés dans l'essai de pénétration de la vapeur pour les produits emballés, par ex. les instruments et matériaux poreux. L’indicateur prévu dans ce but est un indicateur de classe 2, tel que décrit dans l’ISO 111401-1.
Les indicateurs conformes à la présente partie de l’ISO 11140 sont destinés à être utilisés en association avec l’emballage d’essai normalisé tel que décrit dans l’EN 285. La présente partie de l’ISO 11140 ne prend pas en compte la performance de cet emballage, mais spécifie la performance des indicateurs.
Sterilizacija izdelkov za zdravstveno nego – Kemijski indikatorji – 3. del: Sistemi indikatorjev razreda 2 za uporabo pri Bowie-Dickovem preskusu prodiranja pare (ISO 11140-3:2007)
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 11140-3:2007
01-september-2007
1DGRPHãþD
SIST EN 867-3:2000
SIST EN 867-3:2000/AC:2000
Sterilizacija izdelkov za zdravstveno nego – Kemijski indikatorji – 3. del: Sistemi
indikatorjev razreda 2 za uporabo pri Bowie-Dickovem preskusu prodiranja pare
(ISO 11140-3:2007)
Sterilization of health care products - Chemical indicators - Part 3: Class 2 indicator
systems for use in the Bowie and Dick-type steam penetration test (ISO 11140-3:2007)
Sterilisation von Produkten für die Gesundheitsfürsorge - Chemische Indikatoren - Teil 3:
Indikatorsysteme der Klasse 2 zur Verwendung im Bowie-Dick-Dampfdurchdringungstest
(ISO 11140-3:2007)
Stérilisation des produits de santé - Indicateurs chimiques - Partie 3: Systemes
d'indicateurs de classe 2 pour utilisation lors de l'essai de Bowie et Dick de pénétration
de la vapeur (ISO 11140-3:2007)
Ta slovenski standard je istoveten z: EN ISO 11140-3:2007
ICS:
11.080.01 Sterilizacija in dezinfekcija na Sterilization and disinfection
splošno in general
SIST EN ISO 11140-3:2007 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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EUROPEAN STANDARD
EN ISO 11140-3
NORME EUROPÉENNE
EUROPÄISCHE NORM
March 2007
ICS 11.080.01 Supersedes EN 867-3:1997
English Version
Sterilization of health care products - Chemical indicators - Part
3: Class 2 indicator systems for use in the Bowie and Dick-type
steam penetration test (ISO 11140-3:2007)
Stérilisation des produits de santé - Indicateurs chimiques - Sterilisation von Produkten für die Gesundheitsfürsorge -
Partie 3: Systèmes d'indicateurs de Classe 2 pour Chemische Indikatoren - Teil 3: Indikatorsysteme der
utilisation lors de l'essai de Bowie et Dick de pénétration de Klasse 2 zur Verwendung im Bowie-Dick-
la vapeur (ISO 11140-3:2007) Dampfdurchdringungstest (ISO 11140-3:2007)
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 11140-3:2007: E
worldwide for CEN national Members.
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EN ISO 11140-3:2007 (E)
Foreword
This document (EN ISO 11140-3:2007) 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 867-3:1997.
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 11140-3:2007 has been approved by CEN as EN ISO 11140-3:2007 without
any modifications.
2
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INTERNATIONAL ISO
STANDARD 11140-3
Second edition
2007-03-15
Sterilization of health care products —
Chemical indicators —
Part 3:
Class 2 indicator systems for use in the
Bowie and Dick-type steam penetration
test
Stérilisation des produits de santé — Indicateurs chimiques —
Partie 3: Systèmes d'indicateurs de Classe 2 pour utilisation lors de
l'essai de Bowie et Dick de pénétration de la vapeur
Reference number
ISO 11140-3:2007(E)
©
ISO 2007
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ISO 11140-3:2007(E)
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ii © ISO 2007 – All rights reserved
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ISO 11140-3:2007(E)
Contents Page
Foreword. iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions. 2
4 General requirements. 2
5 Indicator system format . 2
6 Performance requirements . 2
7 Packaging and labelling. 3
8 Quality assurance. 4
Annex A (normative) Determination of strength after steam sterilization . 5
Annex B (normative) Estimation of visual difference between colour of the substrate and the
changed (or unchanged) indicator system by determination of relative reflectance density. 6
Annex C (normative) Determination of indicator colour change on exposure to dry saturated
steam. 10
Annex D (normative) Determination of indicator colour change on exposure to dry heat . 11
Annex E (normative) Accelerated ageing of test samples. 12
Annex F (normative) Determination of transfer of indicator to standard test pack on processing . 13
Annex G (normative) Determination of shelf life of the product . 14
Annex H (normative) Steam exposure apparatus. 15
Annex I (normative) Determination of sensitivity of the indicator to the presence of air . 17
Annex J (normative) Air injection system . 18
Annex K (normative) Standard test pack. 20
Bibliography . 21
© ISO 2007 – All rights reserved iii
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ISO 11140-3:2007(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 11140-3 was prepared by Technical Committee ISO/TC 198, Sterilization of health care products.
This second edition cancels and replaces the first edition (ISO 11140-3:2000) 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
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ISO 11140-3:2007(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, is a circumstance
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 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.
Because a range of different tests in different countries has historically been termed the Bowie and Dick test,
the term “Bowie and Dick-type test” is used in this part of ISO 11140.
© ISO 2007 – All rights reserved v
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INTERNATIONAL STANDARD ISO 11140-3:2007(E)
Sterilization of health care products — Chemical indicators —
Part 3:
Class 2 indicator systems for use in the Bowie and Dick-type
steam penetration test
1 Scope
This part of ISO 11140 specifies the requirements for chemical indicators to be used in the steam penetration
test for steam sterilizers for wrapped goods, e.g. instruments and porous materials. The indicator for this
purpose is a Class 2 indicator as described in ISO 11140-1.
Indicators complying with this part of ISO 11140 are intended for use in combination with the standard test
pack as described in EN 285. This part of ISO 11140 does not consider the performance of the standard test
pack, but does specify the performance of the indicator systems.
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 5457, Technical product documentation — Sizes and layout of drawing sheets
ISO 5636-3, Paper and board — Determination of air permeance (medium range) — Part 3: Bendtsen method
ISO 11140-1:2005, Sterilization of health care products — Chemical indicators — Part 1: General
requirements
ISO/CIE 10526:1999, CIE standard illuminants for colorimetry
EN 285:2006, Sterilization — Steam sterilizers — Large sterilizers
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ISO 11140-3:2007(E)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 11140-1 apply.
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.
5 Indicator system format
The indicator system format shall meet the following requirements.
a) It shall consist of indicator reagent uniformly distributed on a substrate 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 easy comparison of the colour change
at the margin with the colour change in the central region.
.
b) It shall have an air porosity not less than 1,7 µm/(Pa s) when tested in accordance with ISO 5636-3 at an
air pressure of 1,47 kPa.
c) It shall have sufficient strength to withstand steam sterilization.
Compliance shall be tested in accordance with Annex A.
d) It shall have a substrate of a colour that is uniform to visual observation.
e) It shall have a difference in reflectance density of not less than 0,3 between the substrate and either the
changed indicator or the unchanged indicator as specified by the manufacturer.
Compliance shall be tested in accordance with Annex B.
f) It shall permit writing in permanent ink to be made legibly on both processed and unprocessed materials.
Markings made before processing shall be legible after processing.
g) It shall be of size A4 in accordance with ISO 5457.
6 Performance requirements
6.1 The indicator shall meet the following requirements.
a) It shall show a uniform colour change complying with 5 e) after exposure to dry saturated steam at
+1,5 +1,5
134 ( ) °C for 3,5 min ± 5 s or after exposure to dry saturated steam at 121 ( ) °C for 15 min ± 5 s or
0 0
both.
Compliance shall be tested in accordance with Annex C.
b) When placed in the centre of a standard test pack, it shall show a non-uniform colour change when the
temperature at the centre of the standard test pack is 2 K lower than the temperature of the chamber
drain of the steam exposure apparatus (see Annex H).
Compliance shall be tested in accordance with Annex I.
2 © ISO 2007 – All rights reserved
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ISO 11140-3:2007(E)
c) It shall show no discernible colour change after exposure to dry heat at (140 ± 2) °C for not less than
30 min.
Compliance shall be demonstrated in accordance with Annex D.
With some indicators a slight colour change can occur. This shall be acceptable if the change that occurs
is markedly different from that brought about by exposure to steam in accordance with 6.1 a) and within
the limits specified by the manufacturer.
d) It shall not visibly transfer indicator reagent to the material of the test load in intimate contact with the
indicator during processing.
Compliance shall be demonstrated in accordance with Annex F.
6.2 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 to the change on exposure to dry
saturated steam [as described in 6.1 a)], and shall have either inactivated the indicator so that no further
change can take place or not affected the performance of the indicator with respect to the requirements of
6.1 a) and 6.1 b).
Compliance shall be tested in accordance with Annex G or by performance testing after accelerated ageing in
accordance with Annex E.
7 Packaging and labelling
7.1 Each substrate on which an indicator reagent has been deposited shall be marked with the operating
temperature(s) for which the product is designed to be used.
7.2 Each indicator shall be marked with a unique code from which the manufacturing history can be traced.
7.3 Each indicator shall be provided with space for the user to record essential cycle information under the
headings:
⎯ department;
⎯ machine No.;
⎯ cycle No.;
⎯ operator;
⎯ date;
⎯ result;
⎯ supervisor.
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. See Figure 1.
7.4 The product shall be packed in such a way as to allow easy separation of individual units of product and
to protect the product from moisture, dust, sunlight and damage in normal transit, to the extent necessary to
ensure that the indicator retains its performance throughout the stated shelf life when stored in accordance
with the manufacturer's instructions.
The manufacturer shall retain documentary evidence demonstrating compliance.
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ISO 11140-3:2007(E)
7.5 The outside of each carton shall be marked with the operating temperature at which the product is
suitable for use.
7.6 The information supplied by the manufacturer (see 5.7 and 5.8 of ISO 11140-1:2005) shall include
sufficient instruction on the use of the indicator to enable correct interpretation of the test results.
Department
Machine No.
Cycle No.
Operator
Date
Result
Supervisor
NOTE Other formats may be used.
Figure 1 — Example of a suitable format
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, in the event of a defect arising, 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 less. An example of the requirements for maintaining records is
[4]
given in ISO 9001 .
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ISO 11140-3:2007(E)
Annex A
(normative)
Determination of strength after steam sterilization
A.1 Apparatus
A.1.1 Steam exposure apparatus, as specified in Annex H.
A.1.2 Standard test pack, as specified in Annex K.
A.1.3 Steam supply, as specified in EN 285.
A.2 Procedure
A.2.1 Expose the indicator, within a standard test pack, to three successive steam exposures at the stated
operating temperature of the indicator system.
A.2.2 Remove the standard test pack from the exposure apparatus and perform a drop test in accordance
with ISO 2248 from a height of 1 m on to a firm horizontal surface.
NOTE Concrete or terrazzo surfaces are suitable.
A.2.3 Remove the indicator from the standard test pack and visually examine for damage.
A.2.4 Repeat this test for each of three separate production batches of the indicator system.
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ISO 11140-3:2007(E)
Annex B
(normative)
Estimation of visual difference between colour of the substrate and the
changed (or unchanged) indicator system by determination of relative
reflectance density
B.1 Principle
The relative reflectance density, D , as defined in ISO 5-1, of the changed or unchanged indicator and the
Rf
substrate are determined in accordance with the methods given below, which are based on ISO 5-3 and
ISO 5-4, to which reference shall also be made.
D = − log R
Rf 10 f
R = Φ /Φ
f c ce
where
Φ is the reflected flux from the indicator;
c
Φ is the reflected flux from the substrate.
ce
To completely define a type of density, spectrally, it is necessary to specify the light source, optics and
spectral response of the measuring system.
B.2 Apparatus
B.2.1 Steam exposure apparatus, as specified in Annex H.
B.2.2 Photoelectric reflectance photometer, as specified in B.3.2.
B.3 Measurement
B.3.1 Illumination
The relative spectral power distribution of the incident flux shall conform to CIE standard illuminant D , in
65
accordance with ISO/CIE 10526:1999.
NOTE This is regarded as equivalent to “Daylight - cloudy northern sky.”
B.3.2 Measuring instrument
B.3.2.1 General
The measuring instrument shall be a photoelectric instrument giving within 0,3 % an indicated reading
proportional to the intensity of light reflected from the surface under test.
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ISO 11140-3:2007(E)
B.3.2.2 Optical geometry
The measuring instrument shall have optical geometry conforming to the requirements of ISO 5-4. This
includes illumination of the specimen at angles between 40° and 50°, viewed along the normal (0°) with an
angle of acceptance (observer angle) of 10°.
The dimensions of the instrument's measurement aperture shall permit the measurement aperture to be
entirely filled with substrate or indicator.
To minimize measurement errors, the optical system should be equipped with a polarizing filter if the surface
to be measured is highly reflecting, e.g. a plastic-coated surface.
B.3.2.3 Spectral response
For the visual reflectance density, the combined spectral sensitivity of the receiver and spectral characteristics
of the components on the efflux section of the measuring instrument shall match the spectral luminance
efficiency in photopic vision, designated V . The product of V and the reflection densitometer illuminance E ,
A
λ λ
wavelength by wavelength, defines the spectral products that the measuring instrument shall have in order to
provide comparison of visual densities. The spectral product of the measuring instrument shall be within
± 20 % of the values given in Table B.1.
NOTE These conditions assume that there is no fluorescence in the optical elements of the instrument or the sample.
B.3.2.4 Calibration
Reflectance density is determined using a perfectly reflecting and perfectly diffusing material as a reference
standard. Such a material does not exist, but the response that would theoretically be obtained from such a
material can be compared with a suitable secondary reference standard, e.g. compressed barium sulfate or
enamelled metal plaques which can then be used to calibrate the densitometer.
The measuring instrument shall be calibrated against reference samples previously calibrated by a National
Reference Laboratory.
The instrument shall indicate values within ± 3 % of the calibrated values of the reference samples.
B.3.2.5 Background
While readings of the reflectance density of the substrate and the indicator are being made, the sample shall
be in contact with a backing material which is spectrally non-selective and diffuse-reflecting and which has an
ISO reflection density as defined in ISO 5-4:1995, Annex A, greater than 1,50.
B.4 Test method
B.4.1 Sample conditioning
Samples shall be conditioned to, and in equilibrium with, (23 ± 2) °C and (50 ± 5) % relative humidity when
tested.
Standardized conditions are recommended because some materials change density with variations in
temperature and relative humidity.
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ISO 11140-3:2007(E)
B.4.2 Procedure
If the relative density of the changed indicator is to be determined, expose the indicator to a cycle of the steam
exposure apparatus at the specified operating temperature, to produce a uniform colour change in the
indicator reagent.
NOTE The samples obtained from the test described in Annex C are suitable for use as the changed indicators.
Determine the relative reflectance density of the indicator reagent on the substrate by using the substrate as
the reference reflectance.
Repeat this test five times for each of three batches of the indicator system.
B.5 Test report
The test report shall contain at least the following information:
a) name and address of the indicator manufacturer;
b) batch numbers of the individual batches of indicator tested;
c) make, model and serial number of the test instrument;
d) calibration details traceable to a national standards authority;
e) temperature chart records of the steam to which the indicators were exposed;
f) mean and r
...
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