ISO/TS 21488:2020

TECHNICAL ISO/TS
SPECIFICATION 21488
First edition
2020-07
Plastics — Test method for exposing
polyolefins outdoors combining
natural weathering and artificial
irradiation
Plastiques — Procédé d'exposition de polyolefines en plein air
combinant une irradiation naturelle et artificielle
Reference number
©
ISO 2020
© ISO 2020
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ii © ISO 2020 – 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 General . 2
5.2 Test chamber . 3
5.3 Artificial radiation source . 3
5.3.1 General. 3
5.3.2 Metal halide lamp . 3
5.3.3 Fluorescent UVA-340 lamp . 3
5.4 Radiometer . 3
5.5 Black-standard/black-panel thermometer . 3
5.6 Specimen holder . 3
5.7 Apparatus to assess changes in properties . 4
6 Test specimens. 4
7 Test conditions . 4
7.1 Radiation . 4
7.2 Relative humidity of air inside the chamber . 4
7.3 Temperature . 4
7.3.1 Black-standard and black-panel temperature (BPT) . . 4
7.3.2 White-standard and white-panel temperature (WPT) . 4
7.3.3 Specimen temperature . 4
7.3.4 Air temperature (AT) . 4
7.4 Time setting of sunrise and sunset . 4
7.5 Exposure conditions . 5
8 Procedure. 5
8.1 General . 5
8.2 Conditioning . 6
8.3 Mounting of test specimen . 6
8.4 Exposure . 6
8.5 Radiant exposure measurement . 6
9 Test report . 6
Annex A (informative) Outdoor weathering supported with artificial radiation at Seosan .8
Annex B (informative) Apparatus for outdoor weathering supported with artificial radiation .13
Bibliography .17
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
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electrotechnical standardization.
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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).
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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
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iv © ISO 2020 – All rights reserved

Introduction
The performance of polyolefin plastics and products exposed outdoors is reduced by various
environmental factors such as UV radiation, heat, humidity, acid rain, etc. Therefore, the estimation of
the lifetime is an important consideration in designing against performance degradation of materials
and products for the outdoor use. Although the outdoor exposure test method provides degradation
caused by the actual environmental factors, it carries a disadvantage of requiring a prolonged testing
period. Outdoor weathering supported with artificial radiation are also available. In all cases, these
methods are often not effective in regions with a low amount of direct radiation. In response to the
questionnaire conducted, over 150 experts by an expert committee on weathering, the majority of
respondents agreed on the need of a method for outdoor weathering supported with artificial radiation
that would be appropriate for the regional climate, especially for the cloudy regions. That is, a document
to be developed which comprise the advantage of outdoor exposure that would generate actual
environmental exposure and the advantage of shortening the exposure time by utilizing the artificial
irradiation. This test method is developed to provide outdoor weathering supported with artificial
irradiation by continuously and sequentially exposing specimens to natural weathering during daytime
and artificial radiation at night time.
The International Organization for Standardization (ISO) draws attention to the fact that it is claimed
that compliance with this document may involve the use of patents concerning apparatus described in
Annex B.
ISO takes no position concerning the evidence, validity and scope of this patent right.
The holder of this patent right has ensured ISO that he/she is willing to negotiate licences under
reasonable and non-discriminatory terms and conditions with applicants throughout the world. In
this respect, the statement of the holder of this patent right is registered with ISO. Information may be
obtained from the patent database available at www .iso .org/ patents.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights other than those in the patent database. ISO shall not be held responsible for identifying
any or all such patent rights.
TECHNICAL SPECIFICATION ISO/TS 21488:2020(E)
Plastics — Test method for exposing polyolefins outdoors
combining natural weathering and artificial irradiation
1 Scope
This document specifies methods for exposing specimen to alternating outdoor weathering supported
with artificial radiation. This method utilizes, as much as possible, the natural outdoor exposure which
are then assisted by the artificial radiation during night time and in cloudy conditions.
This document is applicable to polyolefin materials as well as to products and portions of products.
The artificial and natural outdoor exposures and their practices applicable to this document are
described in ISO 4892-1, ISO 4892-3 and ISO 877-1, ISO 877-2 and ISO 877-3, respectively.
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 877-1, Plastics — Methods of exposure to solar radiation — Part 1: General guidance
ISO 877-2:2009, Plastics — Methods of exposure to solar radiation — Part 2: Direct weathering and
exposure behind window glass
ISO 877-3, Plastics — Methods of exposure to solar radiation — Part 3: Intensified weathering using
concentrated solar radiation
ISO 4582, Plastics — De
...