SIST EN ISO 16474-3:2021

SLOVENSKI STANDARD
oSIST prEN ISO 16474-3:2019
01-november-2019
Barve in laki - Metode izpostavljanja laboratorijskim virom svetlobe - 3. del:
Fluorescentne UV-svetilke (ISO/DIS 16474-3:2019)
Paints and varnishes - Methods of exposure to laboratory light sources - Part 3:
Fluorescent UV lamps (ISO/DIS 16474-3:2019)
Beschichtungsstoffe - Künstliches Bestrahlen oder Bewittern in Geräten - Teil 3: UV-
Fluoreszenzlampen (ISO/DIS 16474-3:2019)
Peintures et vernis - Méthodes d'exposition à des sources lumineuses de laboratoire -
Partie 3: Lampes fluorescentes UV (ISO/DIS 16474-3:2019)
Ta slovenski standard je istoveten z: prEN ISO 16474-3
ICS:
87.040 Barve in laki Paints and varnishes
oSIST prEN ISO 16474-3:2019 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN ISO 16474-3:2019

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oSIST prEN ISO 16474-3:2019
DRAFT INTERNATIONAL STANDARD
ISO/DIS 16474-3
ISO/TC 35/SC 9 Secretariat: BSI
Voting begins on: Voting terminates on:
2019-09-26 2019-12-19
Paints and varnishes — Methods of exposure to laboratory
light sources —
Part 3:
Fluorescent UV lamps
Peintures et vernis — Méthodes d'exposition à des sources lumineuses de laboratoire —
Partie 3: Lampes fluorescentes UV
ICS: 87.040
THIS DOCUMENT IS A DRAFT CIRCULATED
This document is circulated as received from the committee secretariat.
FOR COMMENT AND APPROVAL. IT IS
THEREFORE SUBJECT TO CHANGE AND MAY
NOT BE REFERRED TO AS AN INTERNATIONAL
STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
ISO/CEN PARALLEL PROCESSING
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
Reference number
NATIONAL REGULATIONS.
ISO/DIS 16474-3:2019(E)
RECIPIENTS OF THIS DRAFT ARE INVITED
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
©
PROVIDE SUPPORTING DOCUMENTATION. ISO 2019

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oSIST prEN ISO 16474-3:2019
ISO/DIS 16474-3:2019(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2019
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
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ii © ISO 2019 – All rights reserved

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oSIST prEN ISO 16474-3:2019
ISO/DIS 16474-3:2019(E)

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 2
5 Apparatus . 3
5.1 Laboratory light source . 3
5.2 Test chamber . 6
5.3 Radiometer . 6
5.4 Black-standard/black-panel thermometer . 6
5.5 Wetting and humidity . 7
5.5.1 General. 7
5.5.2 Spray and condensation system . 7
5.6 Specimen holders . 7
5.7 Apparatus to assess changes in properties . 7
6 Test specimens (panels) . 7
6.1 General . 7
6.2 Preparation and coating . . 8
6.3 Drying and conditioning . 8
6.4 Thickness of coating . 8
6.5 Number of test panels . 8
7 Test conditions . 8
7.1 Radiation . 8
7.2 Temperature . 8
7.3 Relative humidity of chamber air . 9
7.4 Condensation and spray cycles . 9
7.5 Complex cycles with dark periods . 9
7.6 Sets of exposure conditions . 9
8 Procedure and mounting of the test specimens .10
8.1 General .10
8.2 Exposure .10
8.3 Measurement of radiant exposure .10
8.4 Determination of changes in properties after exposure .10
9 Test report .11
Annex A (informative) Spectral distribution of radiation for typical fluorescent UV lamps .12
Bibliography .16
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oSIST prEN ISO 16474-3:2019
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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 35, Paints and varnishes, Subcommittee
SC 9, General test methods for paints and varnishes.
This second edition cancels and replaces the first edition (ISO 16474-3:2013), which has been technically
revised.
The main changes compared to the previous edition are as follows:
— in 7.2 the difference between the temperature of a black panel sensor and a black standard sensor
has been corrected;
— in Table 4 it has been changed that the black-panel temperature is not controlled during water spray;
— the text has been editorially revised and the normative references have been updated.
A list of all parts in the ISO 16474 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/members .html.
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Introduction
Coatings of paints, varnishes and similar materials (subsequently referred to simply as coatings) are
exposed to laboratory light sources, in order to simulate in the laboratory the ageing processes which
occur during natural weathering or behind window glass.
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oSIST prEN ISO 16474-3:2019
DRAFT INTERNATIONAL STANDARD ISO/DIS 16474-3:2019(E)
Paints and varnishes — Methods of exposure to laboratory
light sources —
Part 3:
Fluorescent UV lamps
1 Scope
This document specifies methods for exposing coatings to fluorescent UV lamps, heat and water in
apparatus designed to reproduce the weathering effects that occur when materials are exposed in
actual end-use environments to daylight, or to daylight through window glass.
The coatings are exposed to different types of fluorescent UV lamps under controlled environmental
conditions (temperature, humidity and/or water). Different types of fluorescent UV lamp may be used
to meet all the requirements for testing different materials.
Specimen preparation and evaluation of the results are covered in other ISO documents for specific
materials.
General guidance is given in ISO 16474-1.
NOTE Fluorescent UV lamp exposures for plastics are described in ISO 4892-3.
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 1514, Paints and varnishes — Standard panels for testing
ISO 2808, Paints and varnishes — Determination of film thickness
ISO 4618, Paints and varnishes — Terms and definitions
ISO 9370, Plastics — Instrumental determination of radiant exposure in weathering tests — General
guidance and basic test method
ISO 16474-1, Paints and varnishes — Methods of exposure to laboratory light sources — Part 1: General
guidance
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 4618 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at http: //www .iso .org/obp
— IEC Electropedia: available at http: //www .electropedia .org/
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3.1
radiant exposure
H
amount of radiant energy to which a test panel has been exposed
Note 1 to entry: Radiant exposure is given by the equation HE=∫ ⋅dt
where
H is the radiant exposure, in joules per square metre;
E is the irradiance, in watts per square metre;
t is the exposure time, in seconds
Note 2 to entry: If the irradiance E is constant throughout the whole exposure time, the radiant exposure H is
given simply by the product of E and t.
4 Principle
4.1 Fluorescent UV lamps, when properly maintained, can be used to simulate the spectral irradiance
of daylight in the ultraviolet (UV) region of the spectrum.
4.2 Specimens are exposed to various levels of UV radiation, heat and moisture (see 4.4) under
controlled environmental conditions.
4.3 The exposure conditions may be varied by selection of:
a) the type of fluorescent lamp (spectral power distribution);
b) the irradiance level;
c) the temperature during the UV exposure;
d) the relative humidity of the chamber air during the light and dark exposures, when test conditions
requiring control of humidity are used;
NOTE Commercial fluorescent UV lamp devices mostly do not provide means of relative humidity
control.
e) the type of wetting (see 4.4);
f) the wetting temperature and cycle;
g) the timing of the UV/dark cycle.
4.4 Wetting is usually produced by condensation of water vapour onto the exposed specimen surface
or by spraying the test specimens with demineralized/deionized water.
4.5 The procedure(s) may include measurement of the irradiance and the radiant exposure in the
plane of the specimen.
4.6 It is recommended that a similar material of known performance (a control) be exposed
simultaneously with the test specimens to provide a standard for comparative purposes.
4.7 Intercomparison of results obtained from specimens exposed in different apparatus or to different
types of lamp should not be made unless an appropriate statistical relationship has been established
between the different types of equipment for the material to be tested.
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5 Apparatus
5.1 Laboratory light source
5.1.1 Fluorescent UV lamps are fluorescent lamps in which radiant emission in the ultraviolet region of
the spectrum, i.e. below 400 nm, makes up at least 80 % of the total light output. There are three types of
fluorescent UV lamp used in this document:
— Type 1A (UVA-340) fluorescent UV lamp: These lamps have a radiant emission below 300 nm of
less than 1 % of the total light output, have an emission peak at 343 nm, and are more commonly
identified as UVA-340 for simulation of daylight from 300 nm to 340 nm (see Table 1, column A.1).
Figure A.1 is a graph of spectral irradiance from 250 nm to 400 nm of a typical type 1A (UVA-340)
fluorescent lamp compared to daylight.
— Type 1B (UVA-351) fluorescent UV lamp: These lamps have a radiant emission below 310 nm of
less than 1 % of the total light output, have a peak emission at 353 nm, and are more commonly
identified as UVA-351 for simulation of the UV portion of daylight behind window glass (see Table 2).
Figure A.2 is a graph of spectral irradiance from 250 nm to 400 nm of a typical type 1B (UVA-351)
fluorescent UV lamp compared to daylight filtered by window glass.
— Type 2 (UVB-313) fluorescent UV lamp: These lamps are more commonly identified as UVB-313
and have a radiant emission below 300 nm that is more than 10 % of the total output and a peak
emission at 313 nm (see Table 3). Figure A.3 is a graph of the spectral irradiance from 250 nm to
400 nm of two typical type 2 (UVB-313) fluorescent lamps compared to daylight. Type 2 (UVB-313)
lamps may be used only by agreement between the parties concerned. Such agreement shall be
stated in the test report.
NOTE 1 Type 2 (UVB-313) lamps have a spectral distribution of radiation which peaks near the 313 nm
mercury line and might emit radiation down to λ = 254 nm, which can initiate ageing processes that never occur
in end-use environments.
NOTE 2 The solar spectral irradiance for a number of different atmospheric conditions is described in CIE No.
[2]
85 . The benchmark daylight used in this document is from CIE No. 85:1989, Table 4.
5.1.2 Unless otherwise specified, type 1A (UVA-340) fluorescent UV lamps or corresponding type 1A
fluorescent UV lamp combinations shall be used to simulate the UV part of daylight (see Table 4, method
A). Unless otherwise specified, type 1B (UVA-351) lamps shall be used to simulate the UV part of daylight
through window glass (see Table 4, method B).
5.1.3 Fluorescent lamps age significantly with extended use. If an automatic irradiance control system
is not used, follow the apparatus manufacturer’s instructions on the procedure necessary to maintain the
desired irradiance.
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5.1.4 Irradiance uniformity shall be in accordance with the requirements specified in ISO 16474-1.
Requirements for periodic repositioning of specimens when irradiance within the exposure area is less
than 90 % of the peak irradiance are described in ISO 16474-1.
a, b
Table 1 — Relative ultraviolet spectral irradiance for type 1A lamps for daylight UV (method A)
c d,e c
Spectral pass-band Minimum CIE No. 85:1989, Table 4 Maximum
(λ = wavelength in nm) % % %
λ < 290 0 0,1
290 ≤ λ ≤ 320 5,9 5,4 9,3
320 < λ ≤ 360 60,9 38,2 65,5
360 < λ ≤ 400 26,5 56,4 32,8
a
 This table gives the irradiance in the given passband, expressed as a percentage of the total irradiance between 290 nm
and 400 nm. To determine whether a specific type 1A (UVA-340) lamp meets the requirements of this table, the spectral
irradiance from 250 nm to 400 nm shall be measured. Typically, this is done in 2 nm increments. The total irradiance in
each passband is then summed and divided by the total irradiance between 290 nm and 400 nm.
b
 The minimum and maximum limits for type 1A (UVA-340) lamps in this table are based on more than 60 spectral
[3]
irradiance measurements with type 1A (UVA-340) lamps from different production lots and of various ages . The spectral
irradiance data are for lamps within the ageing recommendations of the apparatus manufacturer. As more spectral
irradiance data become available, minor changes in the limits are possible. The minimum and maximum limits are at
least three sigma from the mean for all the measurements. The range of the relative irradiance of fluorescent UV lamp
combinations is determined by radiation measurements at about 50 locations within the exposure area recommended by
the apparatus manufacturer.
c
 The minimum and maximum columns will not necessarily sum to 100 % because they represent the minima and
maxima for the measurement data used. For any individual spectral irradiance distribution, the percentages calculated
for the pass-bands in this table will sum to 100 %. For any individual type 1A (UVA-340) fluorescent lamp, the calculated
percentage in each pass-band shall fall within the minimum and maximum limits given. Test results can be expected
to differ between exposures using type 1A (UVA-340) lamps in which the spectral irradiance differs by as much as that
allowed by the tolerances. Contact the manufacturer of the fluorescent UV apparatus for specific spectral irradiance data
for the type 1A (UVA-340) lamp used.
d
 The data from CIE No. 85:1989, Table 4, is the global solar irradiance on a horizontal surface for an air mass of 1,0, an
ozone column of 0,34 cm at STP, 1,42 cm of precipitable water vapour and a spectral optical depth of aerosol extinction of
0,1 at 500 nm. These data are provided for reference purposes only and are intended to serve as a target.
e For the solar spectrum represented by CIE No. 85:1989, Table 4, the UV irradiance (290 nm to 400 nm) is 11 % and the
visible irradiance (400 nm to 800 nm) is 89 %, expressed as a percentage of the total irradiance from 290 nm to 800 nm.
Because the primary emission of fluorescent UV lamps is concentrated in the 300 nm to 400 nm pass-band, there are
limited data available for the visible light emission of fluorescent UV lamps. The percentages of UV irradiance and visible
irradiance on specimens exposed in fluorescent UV apparatus might vary due to the number of specimens being exposed
and their reflectance properties.
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Table 2 — Relative ultraviolet spectral irradiance for type 1B (UVA 351) lamps for daylight
a, b
behind window glass (method B)
c c
Spectral pass-band Minimum CIE No. 85:1989, Table 4, Maximum
plus effect of window
d,e
glass
(λ = wavelength in nm) % % %
λ < 300 0 0,2
300 ≤ λ ≤ 320 1,1 ≤ 1 3,3
320 < λ ≤ 360 60,5 33,1 66,8
360 < λ ≤ 400 30,0 66,0 38,0
a
 This table gives the irradiance in the given pass-band, expressed as a percentage of the total irradiance between
290 nm and 400 nm. To determine whether a specific type 1B (UVA-351) lamp meets the requirements of this table,
the spectral irradiance from 250 nm to 400 nm shall be measured. Typically, this is done in 2 nm increments. The total
irradiance in each pass-band is then summed and divided by the total irradiance between 290 nm and 400 nm.
b
 The minimum and maximum limits given in this table are based on 21 spectral irradiance measurements with type 1B
[3]
(UVA-351) lamps from different production lots and of various ages . The spectral irradiance data are for lamps within
the ageing recommendations of the apparatus manufacturer. As more spectral irradiance data become available, minor
changes in the limits are possible. The minimum and maximum limits are at least three sigma from the mean for all the
measurements.
c
 The minimum and maximum columns will not necessarily sum to 100 % because they represent the minima and
maxima for the measurement data used. For any individual spectral irradiance distribution, the percentages calculated
for the pass-bands in this table will sum to 100 %. For any individual type 1B (UVA-351) fluorescent lamp, the calculated
percentage in each pass-band shall fall within the minimum and maximum limits given. Test results can be expected
to differ between exposures using type 1B (UVA-351) lamps in which the spectral irradiance differs by as much as that
allowed by the tolerances. Contact the manufacturer of the fluorescent UV apparatus for specific spectral irradiance data
for the type 1B (UVA-351) lamp used.
d
 The data from CIE No. 85:1989, Table 4, plus the effect of window glass was determined by multiplying the CIE
No. 85:1989, Table 4 data by the spectral transmittance of typical 3-mm-thick window glass (see ISO 16474-2, Annex A).
These data are provided for reference purposes only and are intended to serve as a target.
e
 For the solar spectrum represented by CIE No. 85:1989, Table 4, plus window glass data, the UV irradiance from
300 nm to 400 nm is typically about 9 % and the visible irradiance (400 nm to 800 nm) is typically about 91 %, expressed
as a percentage of the total irradiance from 300 nm to 800 nm. Because the primary emission of fluorescent UV lamps is
concentrated in the 300 nm to 400 nm passband, there are limited data available for the visible light emission of fluorescent
UV lamps. The percentages of UV irradiance and visible irradiance on specimens exposed in fluorescent UV apparatus
might vary due to the number of specimens being exposed and their reflectance properties.
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a, b
Table 3 — Relative ultraviolet spectral irradiance for type 2 (UVB 313) lamps (method C)
c d, e c
Spectral passband Minimum CIE No. 85:1989, Table 4 Maximum
(λ = wavelength in nm) % % %
λ < 290 1,3 0 5,4
290 ≤ λ ≤ 320 47,8 5,4 65,9
320 < λ ≤ 360 26,9 38,2 43,9
360 < λ ≤ 400 1,7 56,4 7,2
a
 This table gives the irradiance in the given pass-band, expressed as a percentage of the total irradiance between
250 nm and 400 nm. To determine whether a specific type 2 (UVB-313) lamp meets the requirements of this table, the
spectral irradiance from 250 nm to 400 nm shall be measured. Typically, this is done in 2 nm increments. The total
irradiance in each pass-band is then summed and divided by the total irradiance between 250 nm and 400 nm.
b
 The minimum and maximum limits given in this table are based on 44 spectral irradiance measurements with type 2
[3]
(UVB-313) lamps from different production lots and of various ages . The spectral irradiance data are for lamps within
the ageing recommendations of the apparatus manufacturer. As more spectral irradiance data become available, minor
changes in the limits are possible. The minimum and maximum limits are at least three sigma from the mean for all the
measurements.
c
 The minimum and maximum columns will not necessarily sum to 100 % because they represent the minima and
maxima for the measurement data used. For any individual spectral irradiance distribution, the percentages calculated
for the pass-bands in this table will sum to 100 %. For any individual type 2 (UVB-313) fluorescent lamp, the calculated
percentage in each pass-band shall fall within the minimum and maximum limits given. Test results can be expected to
differ between exposures using type 2 (UVB-313) lamps in which the spectral irradiance differs by as much as that allowed
by the tolerance
...