ISO 11983:2025

International
Standard
ISO 11983
First edition
Road vehicles — Safety glazing
2025-01
materials — Test methods for
electro-switchable glazing
Véhicules routiers — Vitrages de sécurité — Méthodes d'essai
pour vitrages électro-commutables
Reference number
© ISO 2025
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ii
Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Test methods . 2
4.1 Ambient conditions.2
4.2 Regular luminous transmittance .2
4.2.1 Purpose of test .2
4.2.2 Apparatus .2
4.2.3 Measuring state .2
4.2.4 Device under test .2
4.2.5 Procedure .3
4.2.6 Expression of results .3
4.3 Switching time .3
4.3.1 Purpose of test .3
4.3.2 Apparatus .3
4.3.3 Device under test .3
4.3.4 Procedure .3
4.3.5 Expression of results .5
4.4 Haze .5
4.4.1 Purpose of test .5
4.4.2 Apparatus .5
4.4.3 Measuring state .5
4.4.4 Device under test .5
4.4.5 Procedure .5
4.4.6 Expression of results .5
4.5 Insulation resistance.5
4.5.1 Purpose of test .5
4.5.2 Apparatus .5
4.5.3 Device under test .6
4.5.4 Procedure .6
4.5.5 Expression of results .7
4.6 Humidity resistance .7
4.6.1 Purpose of test .7
4.6.2 Apparatus .8
4.6.3 Device under test .8
4.6.4 Procedure .8
4.6.5 Expression of results .8
4.7 Low temperature resistance .8
4.7.1 Purpose of test .8
4.7.2 Apparatus .9
4.7.3 Device under test .9
4.7.4 Procedure .9
4.7.5 Expression of results .9
4.8 Colour uniformity .9
4.8.1 Purpose of test .9
4.8.2 Apparatus .9
4.8.3 Device under test .9
4.8.4 Measuring state .10
4.8.5 Procedure .10
4.8.6 Expression of results .10
4.9 Switching cycles .11
4.9.1 Purpose of test .11

iii
4.9.2 Apparatus .11
4.9.3 Device under test .11
4.9.4 Procedure . 12
4.9.5 Expression of results . 12
4.10 Radiation durability . . 12
4.10.1 Purpose of test . 12
4.10.2 Apparatus . 12
4.10.3 Device under test . 13
4.10.4 Procedure . 13
4.10.5 Expression of results . 13
Annex A (informative) Introduction to different principles of electro-switchable glazing . 14

iv
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
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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 document 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).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
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This document was prepared by Technical Committee ISO/TC 22, Road vehicles, Subcommittee SC 35,
Lighting and visibility.
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.

v
Introduction
This document outlines the test method to evaluate properties of electro-switchable glazing during the
switching period and under stable states of luminous transmittance.
There are various principles of electro-switchable glazing that can be used to produce safety glazing for
road vehicles. See Annex A for a description of these principles. The luminous transmittance states that
the electro-switchable glazing can be switched to and the time it takes to switch between these states are
major concerns for consumers and the market. The lifetime of these different electro-switchable glazing is
influenced by humidity, temperature and radiation. The various principles differ in terms of performance,
but they can be improved applying appropriate voltage or current or applying more complex circuits.

vi
International Standard ISO 11983:2025(en)
Road vehicles — Safety glazing materials — Test methods for
electro-switchable glazing
1 Scope
This document provides the test methods for regular luminous transmittance, switching time, haze,
insulation resistance, humidity resistance, low temperature resistance, colour uniformity, switching cycles
and radiation durability for electro-switchable glazing used on road vehicles.
This document applies to switchable glazing in response to applied voltage or current.
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 3538:1997, Road vehicles — Safety glazing materials — Test methods for optical properties
ISO 4892-2:2013, Plastics — Methods of exposure to laboratory light sources — Part 2: Xenon-arc lamps
ISO 6469-3:2021, Electrically propelled road vehicles — Safety specifications — Part 3: Electrical safety
ISO/CIE 11664-6, Colorimetry — Part 6: CIEDE2000 colour-difference formula
ISO 13837:2021, Road vehicles — Safety glazing materials — Method for the determination of solar
transmittance
ISO 14782:2021, Plastics — Determination of haze for transparent materials
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
electro-switchable glazing
glazing comprised of one or more panes of material whose transmittance properties can be altered in
response to an applied voltage or current
3.2
highest transmittance state
stable state as glazing switched to highest regular luminous transmittance (3.4) under specific conditions
Note 1 to entry: This is also referred to as the clear state or bleached state.

3.3
lowest transmittance state
stable state as glazing switched to lowest regular luminous transmittance (3.4) under specific conditions
Note 1 to entry: This is also referred to as the tinted state, dark state, or coloured state.
3.4
regular luminous transmittance
light transmittance from 380 nm to 780 nm measured perpendicularly to the glazing without considering
diffused light
3.5
tinting time
period of electro-switchable glazing (3.1) switching from highest transmittance state (3.2) to lowest
transmittance state (3.3)
3.6
switching cycle
electro-switchable glazing (3.1) switched from lowest/highest transmittance state (3.2) to highest/lowest
transmittance state (3.3) and back to lowest/highest transmittance state with each process finished once
4 Test methods
4.1 Ambient conditions
Unless otherwise specified, the tests shall be conducted under the following conditions:
a) ambient temperature: (23 ± 5) °C;
4 5
b) atmospheric pressure: 8,06 × 10 Pa to 1,06 × 10 Pa (860 mbar to 1 060 mbar);
c) relative humidity:(60 ± 20) %.
4.2 Regular luminous transmittance
4.2.1 Purpose of test
The purpose of this test is to determine regular luminous transmittance of electro-switchable glazing in
different transmittance states.
4.2.2 Apparatus
4.2.2.1 Control system, which shall be provided by the manufacturers for switching the device under test
(DUT) to a different state. The control system and parameters shall be pre-set to make the specimen switch
same as finished product.
4.2.2.2 Regular luminous transmittance measuring system, which is described in ISO 3538:1997, 5.1.2.
4.2.3 Measuring state
The regular luminous transmittance of any state that the glazing can be switched to, may be measured.
4.2.4 Device under test
One specimen or finished product may be used as the DUT.

4.2.5 Procedure
Before measuring regular luminous transmittance, switch the DUT for at least five cycles.
Then, switch the whole DUT to required state and keep it in that state for about 5 min. Measure regular
luminous transmittance of the DUT according to ISO 3538:1997, 5.1.3.
4.2.6 Expression of results
Record the regular luminous transmittance and the corresponding state of DUT. The value shall be rounded
to 0,1 %.
4.3 Switching time
4.3.1 Purpose of test
The purpose of this test is to determine the switching time between different states of electro-switchable
glazing.
4.3.2 Apparatus
4.3.2.1 Spectrophotometer, which has the time drive function and whose time interval can be switched to
1 s or shorter. An equivalent photometer can be used, but the light output shall be filtered to 550 nm ± 5 nm
or other required wavelengths, and the measurements shall be recorded per sec
...