ISO 21475:2019

Plastics — Methods of exposure to determine the wavelength dependent degradation using spectrally dispersed radiation

This document specifies methods of determining the spectral response of all kind of plastics materials to ultraviolet and visible radiation by an irradiation test with spectrally dispersed irradiation. NOTE Typical specimens that are evaluated include: films, liquids, plaques, pellets, powders, sheets and discs.

Plastiques — Méthodes d'exposition pour déterminer la dégradation dépendante de la longueur d'onde en utilisant un rayonnement dispersé spectralement

General Information

• Status: Published
• Publication Date: 22-May-2019
• ICS: 83.080.01 - Plastics in general
• Technical Committee: ISO/TC 61/SC 6 - Ageing, chemical and environmental resistance
• Drafting Committee: ISO/TC 61/SC 6/WG 2 - Exposure to light

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 21475
First edition
2019-05
Plastics — Methods of exposure to
determine the wavelength dependent
degradation using spectrally
dispersed radiation
Plastiques — Méthodes d'exposition pour déterminer la dégradation
dépendante de la longueur d'onde en utilisant un rayonnement
dispersé spectralement
Reference number
©
ISO 2019
© ISO 2019
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting
on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address
below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Fax: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii © ISO 2019 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 2
5 Apparatus . 2
5.1 Exposure device . 2
5.2 Spectroradiometer . 3
5.3 Measuring device for property change . 3
6 Test specimens. 3
6.1 Specimen preparation and conditioning . 3
6.2 Specimen conditioning . . 4
7 Exposure parameter . 4
7.1 Radiation . 4
7.2 Specimen temperature . 4
7.3 Test duration . 5
8 Procedure. 5
8.1 Specimen optical and mechanical properties measurements . 5
8.2 Mounting test specimens . 5
8.3 Exposure . 5
9 Test report . 6
Annex A (informative) General information on the test method using spectrally dispersed
radiation . 7
Annex B (informative) Examples of devices for spectrally dispersed irradiation .9
Annex C (informative) Examples of test results .11
Bibliography .18
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 61, Plastics, Subcommittee SC 6, Ageing,
chemical and environmental resistance.
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 2019 – All rights reserved

Introduction
Plastics are used outdoors and indoors where they are exposed to solar radiation, to solar radiation
filtered by window glass and to artificial radiation sources for long periods. Therefore, information
on the wavelength dependent degradation of a polymer property (e.g. optical and mechanical) within
the ultraviolet and visible solar spectrum is important. The results of this test determine the spectral
sensitivity of a property change over the range of the ultraviolet and the visible solar spectrum.
INTERNATIONAL STANDARD ISO 21475:2019(E)
Plastics — Methods of exposure to determine the
wavelength dependent degradation using spectrally
dispersed radiation
1 Scope
This document specifies methods of determining the spectral response of all kind of plastics materials
to ultraviolet and visible radiation by an irradiation test with spectrally dispersed irradiation.
NOTE Typical specimens that are evaluated include: films, liquids, plaques, pellets, powders, sheets and discs.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements 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 291, Plastics — Standard atmospheres for conditioning and testing
ISO 472, Plastics — Vocabulary
ISO 4582, Plastics — Determination of changes in colour and variations in properties after exposure to
glass-filtered solar radiation, natural weathering or laboratory radiation sources
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 472 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https: //www .iso .org/obp
— IEC Electropedia: available at http: //www .electropedia .org/
3.1
short-pass filter
filter that transmits wavelengths shorter than the cut-off wavelength while rejecting longer
wavelengths, and characterized by a sharp transition from maximum to minimum transmittance
[SOURCE: ISO 9370:2017, 3.31]
3.2
long-pass filter
filter that transmits wavelengths longer than the cut-on wavelength while rejecting shorter
wavelengths, and characterized by a sharp transition from minimum to maximum transmittance
[SOURCE: ISO 9370:2017, 3.21]
3.3
file specimens
portion of the material to be tested which is stored under conditions in which it is stable and which is
used for comparison between the exposed and unexposed states
[SOURCE: ISO 4892-1:2016, 3.2]
3.4
action spectrum
description of the spectral efficiency of radiation to produce a particular polymer response (change in a
specific property of a specific polymer) as a function of wavelength
Note 1 to entry: Data of an action spectrum are specific to the polymer but independent of the radiation source.
This term is also known as spectral sensitivity.
3.5
reciprocal linear dispersion of the radiation
wavelength dispersion in the focal plane
Note 1 to entry: It is expressed in nm/mm.
3.6
spatial resolution of the exposure device
width of the image of the entrance slit in the specimen plane, to be calculated by the slit width multiplied
by the reciprocal linear dispersion
3.7
spectral irradiance
E
λ
irradiance per wavelength interval
−2 −1
Note 1 to entry: It is typically reported in watts per square metre per nanometre (W⋅m ⋅nm ).
[SOURCE: ISO 9370:2017, 3.20]
3.8
spectral radiant exposure
time integral of spectral irradiance (3.7)
−2 −1
Note 1 to entry: It is expressed in joules per square metre per nanometre (J⋅m ⋅nm ).
4 Principle
A specimen is exposed to spectrally dispersed radiation. This exposure causes wavelength dependent
degradation of a test specimen. The position of the degradation of a test specimen is a function of
wavelength. Analysis of these parameters enables a quantitative evaluation of the degradation as a
function of wavelength.
Additionally, the action spectrum can be quantified, by spatial measurement of both spectral irradiance
and the resulting changes in the test specimen property.
Temperature control of the test specimen may be used.
NOTE General information on the test method is described in Annex A. Examples of devices for spectrally
dispersed irradiation are shown in Annex B. Examples of test result are shown in Annex C.
5 Apparatus
5.1 Exposure device
The radiation source shall provide radiation covering the entire wavelength range under investigation,
which is typically around 200 nm to 700 nm. If the light source generates ozone, the ozone shall be
removed using an ozone treatment system.
NOTE 1 Typically, a Xenon arc lamp is used.
2 © ISO 2019 – All rights reserved

The radiation is directed to an entrance slit of an optical system. The width of the entrance slit
determines the spectral resolution and the irradiance of spectrally dispersed radiation. A narrower
entrance slit results in higher resolution and lower irradiance. Conversely, a wider entrance slit results
in lower resolution and higher irradiance.
The radiation through the entrance slit is spectrally dispersed by means of a diffraction grating which
should be widely illuminated. In order to optimize the deflection to get only one deflection order for a
specific wavelength range, a blaze grating may be used.
For optical geometry, various imaging optical elements whose spectral characteristics should be
optimized for ultraviolet and visible radiation ca
...

INTERNATIONAL ISO
STANDARD 21475
First edition
2019-05
Plastics — Methods of exposure to
determine the wavelength dependent
degradation using spectrally
dispersed radiation
Plastiques — Méthodes d'exposition pour déterminer la dégradation
dépendante de la longueur d'onde en utilisant un rayonnement
dispersé spectralement
Reference number
©
ISO 2019
© ISO 2019
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting
on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address
below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Fax: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii © ISO 2019 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 2
5 Apparatus . 2
5.1 Exposure device . 2
5.2 Spectroradiometer . 3
5.3 Measuring device for property change . 3
6 Test specimens. 3
6.1 Specimen preparation and conditioning . 3
6.2 Specimen conditioning . . 4
7 Exposure parameter . 4
7.1 Radiation . 4
7.2 Specimen temperature . 4
7.3 Test duration . 5
8 Procedure. 5
8.1 Specimen optical and mechanical properties measurements . 5
8.2 Mounting test specimens . 5
8.3 Exposure . 5
9 Test report . 6
Annex A (informative) General information on the test method using spectrally dispersed
radiation . 7
Annex B (informative) Examples of devices for spectrally dispersed irradiation .9
Annex C (informative) Examples of test results .11
Bibliography .18
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 61, Plastics, Subcommittee SC 6, Ageing,
chemical and environmental resistance.
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 2019 – All rights reserved

Introduction
Plastics are used outdoors and indoors where they are exposed to solar radiation, to solar radiation
filtered by window glass and to artificial radiation sources for long periods. Therefore, information
on the wavelength dependent degradation of a polymer property (e.g. optical and mechanical) within
the ultraviolet and visible solar spectrum is important. The results of this test determine the spectral
sensitivity of a property change over the range of the ultraviolet and the visible solar spectrum.
INTERNATIONAL STANDARD ISO 21475:2019(E)
Plastics — Methods of exposure to determine the
wavelength dependent degradation using spectrally
dispersed radiation
1 Scope
This document specifies methods of determining the spectral response of all kind of plastics materials
to ultraviolet and visible radiation by an irradiation test with spectrally dispersed irradiation.
NOTE Typical specimens that are evaluated include: films, liquids, plaques, pellets, powders, sheets and discs.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements 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 291, Plastics — Standard atmospheres for conditioning and testing
ISO 472, Plastics — Vocabulary
ISO 4582, Plastics — Determination of changes in colour and variations in properties after exposure to
glass-filtered solar radiation, natural weathering or laboratory radiation sources
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 472 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https: //www .iso .org/obp
— IEC Electropedia: available at http: //www .electropedia .org/
3.1
short-pass filter
filter that transmits wavelengths shorter than the cut-off wavelength while rejecting longer
wavelengths, and characterized by a sharp transition from maximum to minimum transmittance
[SOURCE: ISO 9370:2017, 3.31]
3.2
long-pass filter
filter that transmits wavelengths longer than the cut-on wavelength while rejecting shorter
wavelengths, and characterized by a sharp transition from minimum to maximum transmittance
[SOURCE: ISO 9370:2017, 3.21]
3.3
file specimens
portion of the material to be tested which is stored under conditions in which it is stable and which is
used for comparison between the exposed and unexposed states
[SOURCE: ISO 4892-1:2016, 3.2]
3.4
action spectrum
description of the spectral efficiency of radiation to produce a particular polymer response (change in a
specific property of a specific polymer) as a function of wavelength
Note 1 to entry: Data of an action spectrum are specific to the polymer but independent of the radiation source.
This term is also known as spectral sensitivity.
3.5
reciprocal linear dispersion of the radiation
wavelength dispersion in the focal plane
Note 1 to entry: It is expressed in nm/mm.
3.6
spatial resolution of the exposure device
width of the image of the entrance slit in the specimen plane, to be calculated by the slit width multiplied
by the reciprocal linear dispersion
3.7
spectral irradiance
E
λ
irradiance per wavelength interval
−2 −1
Note 1 to entry: It is typically reported in watts per square metre per nanometre (W⋅m ⋅nm ).
[SOURCE: ISO 9370:2017, 3.20]
3.8
spectral radiant exposure
time integral of spectral irradiance (3.7)
−2 −1
Note 1 to entry: It is expressed in joules per square metre per nanometre (J⋅m ⋅nm ).
4 Principle
A specimen is exposed to spectrally dispersed radiation. This exposure causes wavelength dependent
degradation of a test specimen. The position of the degradation of a test specimen is a function of
wavelength. Analysis of these parameters enables a quantitative evaluation of the degradation as a
function of wavelength.
Additionally, the action spectrum can be quantified, by spatial measurement of both spectral irradiance
and the resulting changes in the test specimen property.
Temperature control of the test specimen may be used.
NOTE General information on the test method is described in Annex A. Examples of devices for spectrally
dispersed irradiation are shown in Annex B. Examples of test result are shown in Annex C.
5 Apparatus
5.1 Exposure device
The radiation source shall provide radiation covering the entire wavelength range under investigation,
which is typically around 200 nm to 700 nm. If the light source generates ozone, the ozone shall be
removed using an ozone treatment system.
NOTE 1 Typically, a Xenon arc lamp is used.
2 © ISO 2019 – All rights reserved

The radiation is directed to an entrance slit of an optical system. The width of the entrance slit
determines the spectral resolution and the irradiance of spectrally dispersed radiation. A narrower
entrance slit results in higher resolution and lower irradiance. Conversely, a wider entrance slit results
in lower resolution and higher irradiance.
The radiation through the entrance slit is spectrally dispersed by means of a diffraction grating which
should be widely illuminated. In order to optimize the deflection to get only one deflection order for a
specific wavelength range, a blaze grating may be used.
For optical geometry, various imaging optical elements whose spectral characteristics should be
optimized for ultraviolet and visible radiation ca
...