Plastics are often used outdoors or indoors where they are exposed to solar radiation for extended periods, either through glass or through glass. Therefore, determining the effects of solar radiation, heat, humidity, and other climatic stresses on the color and other properties of plastics is crucial. Outdoor exposure to solar radiation and solar radiation filtered through window glass is described in the ISO 877 series of standards. However, it is often necessary to more rapidly determine the effects of radiation, heat, and humidity on the physical, chemical, and optical properties of plastics through artificially accelerated weathering or artificially accelerated irradiation using specific laboratory light sources. These exposures in laboratory devices are conducted under more controlled conditions than those found in natural environments and are intended to accelerate ultimate polymer degradation and product failure.
Correlating the results of accelerated weathering or artificial accelerated irradiation exposure to those obtained under actual use conditions is difficult due to the variability in both types of exposure and the fact that laboratory tests can never fully reproduce all the exposure stresses experienced by plastics exposed under actual use conditions. No laboratory exposure test can be considered a complete simulation of actual use exposures. The relative durability of materials under actual use exposures can vary significantly depending on the location of exposure due to variations in UV radiation, duration of wetness, temperature, contaminants, and other factors.
The standard “EN ISO 4892 Plastics - Methods of exposure to laboratory light sources”, which is a European standard and subsequently published by the International Organization for Standardization (ISO), consists of the following subsections published under the same title:
In this standard, the term "light source" refers to radiation sources that emit UV radiation, visible radiation, infrared radiation, or any combination of these types of radiation. This standard also provides guidance on the interpretation of data obtained from artificial accelerated weathering or artificial accelerated irradiation. More detailed information on methods for determining post-exposure changes in the properties of plastics and reporting these results is provided in EN ISO 4582.
In principle, samples to be tested are exposed to laboratory light sources under controlled ambient conditions. The methods described include the requirements for measuring the irradiance and exposure at the sample plane, the temperature of the specified white and black sensors, the room air temperature, and the relative humidity.
In principle, a xenon arc equipped with filters is used to simulate the relative spectral irradiance of daylight in the ultraviolet (UV) and visible regions of the spectrum. Samples are exposed to various exposures to light, temperature, relative humidity, and water under controlled environmental conditions.
Exposure conditions vary depending on:
Wetting is achieved by spraying test samples with demineralized/deionized water, immersing them in water, or condensing water vapor on the sample surfaces. This procedure involves measuring UV irradiance at the sample plane and UV radiation exposure. Simultaneous exposure of a similar material (control) with known performance to the test samples is recommended to provide a standard for comparison. Comparison of results obtained from samples exposed in different instruments should not be performed unless a suitable statistical relationship can be established between the instruments for the specific exposed material.
Samples are exposed to fluorescent UV lamps under controlled environmental conditions (temperature, humidity, and/or water). Different types of fluorescent UV lamps can be used to meet all the requirements for testing different materials. Sample preparation and results evaluation are covered in other international standards for specific materials. General guidance is provided in EN ISO 4892-1. Fluorescent UV lamp exposures for paints, varnishes, and other coatings are described in ISO 11507.
In principle, fluorescent UV lamps can be used to simulate the spectral irradiance of global solar radiation in the short-wavelength ultraviolet (UV) region of the spectrum, provided the manufacturer's recommendations for lamp maintenance or rotation are followed. Samples are exposed to varying levels of UV radiation, temperature, and humidity under controlled environmental conditions.
Exposure conditions vary depending on:
Wetting usually occurs by condensation of water vapor on the exposed sample surface or by spraying demineralized/deionized water onto test samples. Procedures may include measuring the irradiance intensity and irradiance exposure at the sample plane. To provide a standard for comparison, simultaneous exposure of a similar material of known performance (a control) with the test samples is recommended. Comparison of results obtained from samples exposed to different types of equipment or different types of lamps should not be made unless a suitable statistical relationship has been established between the different types of equipment for the material to be tested.
Samples are exposed to a filtered open-flame carbon arc lamp under controlled ambient conditions (temperature, humidity). Various filters are described. Sample preparation and evaluation of results are covered in other international standards for specific materials. General guidance is provided in EN ISO 4892-1.
In principle, material samples to be tested are exposed to glass-filtered open flame carbon arc light, heat and humidity in continuous or repetitive cycles.
Exposure conditions vary depending on:
The effect of humidity is usually achieved by controlling air humidity, spraying demineralized/deionized water on test samples, or condensing water vapor on the sample surfaces. The procedure may include measuring the irradiance and radiation exposure at the surface of the samples. Simultaneous exposure of a similar material (control) with known behavior to the test samples is recommended to provide a reference standard for comparison. Comparison of results obtained from samples exposed in different instruments should not be performed unless a suitable statistical relationship between the instruments for the specific material being tested has been established.
In short, the EN ISO 4892 series of standards is important because it defines methods for exposing plastic materials to laboratory light sources to assess their resistance to weathering and aging caused by light, heat, and humidity. This is critical for assessing the durability and performance of materials used outdoors or in light-exposed environments.
This set of standards is considered important for the following reasons:
As a result, the EN ISO 4892 set of standards is essential for ensuring the durability, safety, and performance of plastic products in light. These standards are the cornerstone of quality assurance, product development, and compliance across a variety of industries, from automotive and construction to electronics and packaging.
Our organization, which has been operating for many years and meticulously follows global developments in science and technology, employs a team of experienced professionals and a broad infrastructure to conduct testing, measurement, and analysis in a wide range of areas for businesses across all sectors. In this context, we also provide testing services in accordance with the EN ISO 4892 Plastics - Methods of Exposure to Laboratory Light Sources standard.
To get an appointment, to get more detailed information or to request an evaluation, you can ask us to fill in our form and reach you.
