🔩 General guidance and requirements for the selection and application of the methods of exposure of plastics to laboratory light sources from the other parts of ISO 4892 (xenon-arc, fluorescent UV and carbon-arc lamps) and general requirements for artificial accelerated weathering and irradiation devices — irradiance, temperature (black- and white-panel and standard thermometers), humidity and wetting, specimens, exposure conditions and periods, control and reference materials and interpretation of results, PN-EN ISO 4892-1

Materials and NDT PN-EN ISO 4892-1

Overview

WHAT THE STANDARD COVERS. We read the text of the standard in two iTeh samples: SIST EN ISO 4892-1:2024 (English text) — title page of EN ISO 4892-1:2024, European foreword, contents, ISO foreword and introduction — and ISO 4892-1:2024 (French version) — from the title page to 4.3.2 (reference material exposed together with the test material) on page 5. Outside the samples remain the requirements for devices (5: irradiance, temperature, humidity and wetting, other requirements), specimens (6), conditions and procedure (7), exposure periods and evaluation of results (8), test report (9) and Annexes A (measuring irradiance uniformity, normative), B (factors decreasing correlation with actual-use exposures) and C (solar spectral irradiance standards).

ACCORDING TO THE TEXT OF ISO 4892-1:2024 AND THE FOREWORD OF EN ISO 4892-1:2024. The standard was prepared by ISO/TC 61 “Plastics”, Subcommittee SC 6 “Ageing, chemical and environmental resistance”, in collaboration with CEN/TC 249 “Plastics” (secretariat SIS; Vienna Agreement); EN ISO 4892-1:2024 supersedes EN ISO 4892-1:2016 and adopts ISO without modification. The fourth edition replaces the third (ISO 4892-1:2016) as a technical revision; main changes: the definitions of file specimen (3.2) and weathering reference material (3.5), artificial accelerated weathering (3.3) and artificial accelerated irradiation (3.4) were clarified, definitions of black-panel, black-standard, white-panel and white-standard thermometers were added (3.7–3.10), a reference to ISO/TR 18486 was added in 4.2.4, calibration requirements were clarified (5.1.7, 5.2.8, 5.2.9, 5.3.6) as were requirements for thermometers in 5.2 and Table 2, a reference to ISO 23741 was added in 5.3.1, a new subclause 7.3 (sampling for intermediate and final evaluation) was added, test report requirements were updated, and CIE 85 was replaced by CIE 241 in Annex C. Introduction: plastics are often used outdoors or indoors where they are exposed for long periods to solar radiation or solar radiation filtered by window glass; outdoor exposures are described in ISO 877, but it is often necessary to determine the effects of radiation, heat and moisture rapidly by artificial accelerated weathering or irradiation in laboratory devices operated under more controlled conditions than natural ones; relating the results to actual use is difficult because both types of exposure vary and a laboratory test never reproduces exactly all the stresses — no single test is a total simulation; the relative durability of materials can differ greatly depending on the exposure location (UV, time of wetness, temperature, pollutants), so results useful for one location need not be useful for another. Scope (1): general guidance and requirements for selecting and applying the exposure methods of the other parts of ISO 4892 and general performance requirements for devices exposing plastics to laboratory light sources — the information on device requirements is intended for manufacturers of the apparatus; the document also gives information on interpreting test data, but does not contain specific methods for determining property changes of plastics after exposure or reporting them. References (2): ISO 291, ISO 2818, ISO 4582, ISO 4892-2, -3, -4, ISO 9370, ASTM G113. Terms (3, alongside ASTM G113): control material — similar in composition and construction to the test material, exposed together with it for comparison; file specimen — a portion of the material stored under conditions causing minimal degradation (usually dark, dry, moderate temperature), for comparing exposed and unexposed states; artificial accelerated weathering — exposure in a laboratory device simulating accelerated outdoor weathering by radiation, temperature and moisture, usually including liquid water (conditions may be cyclic and intensified, possibly e.g. acid spray to simulate air pollution); artificial accelerated irradiation — the same, but moisture usually only as relative humidity, without liquid water (simulating radiation behind window glass or indoor lighting, so-called fading or lightfastness tests); weathering reference material — of known performance under solar radiation, heat and moisture; reference specimen; black-panel thermometer (BPT) — a flat black metal plate with the sensor at the front, uninsulated, usually indicating lower temperatures than a black-standard thermometer (BST) — a plate insulated at the back with the sensor at the back, indicating one of the highest temperatures in the specimen plane; correspondingly white-panel (WPT) and white-standard (WST) thermometers. Principle (4.1): specimens are exposed to laboratory light sources under controlled conditions, with measurement of irradiance and radiant exposure in the specimen plane, the temperature of specified black and white thermometers, chamber air temperature and relative humidity; “light source” means a source emitting UV, visible or infrared radiation or any combination of them. Significance (4.2): no laboratory test is a total simulation; results can be regarded as representative of actual use only once the degree of correlation has been established for the specific materials and with a similar type and mechanism of degradation; a specific exposure time or radiant exposure cannot generally be related to a definite time in use, so it is wrong to assign a general acceleration factor — because it depends on the material and formulation, on the variability of degradation rate, and if calculated from the irradiance ratio it ignores temperature, humidity and spectral differences; correlation is decreased by e.g.: spectral differences from solar radiation (comparison according to ISO/TR 18486), irradiance higher than in use, continuous exposure without dark periods, specimen temperatures that are too high, unrealistic temperature differences between light and dark specimens, very frequent temperature cycling or thermal shock, unrealistic humidity, and absence of biological agents, pollutants, acid precipitation and condensation (details in Annex B). Use (4.3): results are best used to compare the relative performance of materials tested together under the same conditions in the same device, e.g. by the time or radiant exposure needed to reduce a property to a specified level; it is strongly recommended to expose at least one control material of similar composition and failure type in each test, preferably two — of relatively good and relatively poor durability; enough replicates are needed for statistical evaluation — unless otherwise specified, at least three for each control and test material, and for destructive tests a separate set of specimens for each exposure period; in some specifications test materials are exposed together with a reference material (e.g. blue wool) and measured after it reaches a specified change — if its composition differs, it may be insensitive to stresses that damage the test material or very sensitive to stresses of little effect on it.

STATUS (as of 03.10.2026). The PKN search (term “PN-EN ISO 4892-1”, 03.10.2026) shows PN-EN ISO 4892-1:2025-04 (English version, “Introduces: EN ISO 4892-1:2024 [IDT], ISO 4892-1:2024 [IDT]”) without a withdrawal note and the withdrawn PN-EN ISO 4892-1:2016-06 (English version, replaced by PN-EN ISO 4892-1:2025-04) and PN-EN ISO 4892-1:2001 (Polish version). In the iTeh catalogue (read on 03.10.2026) ISO 4892-1:2024 has the status “Published”, stage 60.60 since 02.10.2024.

HOW MANY LABORATORIES AND IN WHAT FORM (copy of the accreditation scope database, load up to 17.09.2026, read on 03.10.2026). The number 4892-1 appears in 5 records at 5 laboratories: AB 163, AB 369, AB 910, AB 1256, AB 1552. In the current PCA documents (read on 03.10.2026, issues from 26.11.2025 to 01.09.2026) the number appears in 5 rows — one at each; in each of the five documents the number of page markers equals the number of PDF pages, without repetitions; a search of all 1291 PCA documents downloaded from BIP on 03.10.2026 found no laboratories outside the database copy (17 laboratories on the list have no link to a scope document on BIP). The form “PN-EN ISO 4892-1:2025-04” (AB 163, AB 369, AB 1256), the withdrawn “PN-EN ISO 4892-1:2016-06” (AB 1552) and “PN-EN ISO 4892-1” without year (AB 910); always in one cell with other parts of ISO 4892 (2 or 3), at AB 163, AB 910 and AB 1552 also with PN-EN ISO 16474. None of these items is suspended. The “Laboratories” tab (term “PN-EN ISO 4892-1”) shows all 5 laboratories — checked with a tab query on the production server labcoda.pl on 03.10.2026.

WHAT THE LABORATORIES TEST (items in PCA). Object: varnish coatings and plastics (AB 163), building products and materials, plastic products (AB 369), materials for the production of consumer products, including children’s articles, plastics, textiles, paints, varnishes (AB 910, item in the flexible scope of accreditation), construction products and plastic products — plates up to 6 mm thick (AB 1256), construction products and materials, building hardware, parts of machines and electrical equipment, including mining (AB 1552). Characteristic: resistance to weathering and artificial radiation, UV exposure method (AB 163), resistance to a light source (AB 369), resistance to light radiation and weathering, exposure and assessment of colour change (AB 910), resistance to accelerated ageing — exposure to UV-A 351 fluorescent lamps without spraying (AB 1256), resistance to daylight under controlled environmental conditions (AB 1552).

WHERE A SEEMINGLY CORRECT RESULT IS EASY TO GET. With conversion to service time: there is no general acceleration factor; correlation has to be established for the given material (4.2.2, 4.2.3). With comparison of materials: only when they were tested together, under the same conditions and in the same device (4.3.1). With control: a control material in each test, preferably two (4.3.1.1). With the number of specimens: at least three replicates; for destructive tests a separate set for each period (4.3.1.2). With the reference material: a different composition can distort the assessment (4.3.2). With temperature: BPT usually indicates a lower temperature than BST under the same conditions (3.7, 3.8). With the edition: one laboratory cites the withdrawn 2016 edition.

WHAT WE DO NOT GIVE. We did not read the numerical requirements for devices (tolerances of irradiance, temperature, humidity, calibration), requirements for specimens, exposure conditions and periods, evaluation of results or the content of the report (Clauses 5–9, Annexes A–C). Specific exposure cycles are given in Parts 2–4 of the series.

Method principle

Plastic specimens are exposed in a laboratory device to a light source (xenon-arc, fluorescent UV or carbon-arc — according to Parts 2–4) under controlled conditions, measuring irradiance and radiant exposure in the specimen plane, the temperature of black or white panel or standard thermometers, air temperature and humidity. Property changes are assessed against file specimens and control materials exposed at the same time; the result serves primarily to compare the relative durability of materials.

Applications

• Selection and application of methods of exposing plastics to laboratory light sources from Parts 2–4 of ISO 4892 (1)
• General requirements for artificial accelerated weathering and irradiation devices — information for apparatus manufacturers (1)
• Coatings, plastics, construction and consumer products, building hardware and equipment parts — items in the accreditation scopes of 5 laboratories in PCA

Key parameters

Standard

Standard number

PN-EN ISO 4892-1:2025-04

Title (PL)

Tworzywa sztuczne — Metody ekspozycji na laboratoryjne źródła światła — Część 1: Wytyczne ogólne i wymagania

Title (EN)

Plastics — Methods of exposure to laboratory light sources — Part 1: General guidance and requirements

Step-by-step procedure

1. Choice of method

   Part 2 (xenon), 3 (fluorescent UV) or 4 (carbon arc) according to the application (1, 2). PN-EN ISO 4892-1:2025-04 without a withdrawal note (03.10.2026).

2. Specimens and control

   At least three replicates, control material (preferably two), file specimens (3.2, 4.3.1).

3. Exposure

   Controlled irradiance, temperature, humidity; conditions according to Clause 7 and Parts 2–4 (not read).

4. Evaluation

   Comparison with the file specimen and control material, e.g. time or radiant exposure to a specified property change (4.3.1); details in Clause 8 (not read).

Required equipment and apparatus

Reagents, media and consumables

Health and safety (OHS)

• UV radiation from lamps — do not look into the source, device shields
• Hot parts of the exposure chamber

Frequently asked questions