SIST EN ISO 877-3:2026

Overview

SIST EN ISO 877-3:2026 establishes a standardized method for exposing plastics to intensified solar radiation to simulate accelerated weathering. By utilizing reflecting concentrators-commonly referred to as Fresnel reflectors-this method concentrates sunlight onto plastic specimens, multiplying the effects of natural weather exposures. This approach enables industries and researchers to rapidly assess the weathering resistance, durability, and long-term properties of plastic materials in much shorter time frames.

Weathering and aging due to sunlight are critical factors affecting the performance of plastics used in outdoor and automotive applications, construction, and packaging. By following the procedures outlined in this standard, organizations ensure consistency, reliability, and comparability in their weathering test results.

Key Topics

• Accelerated weathering of plastics: Using concentrated solar radiation to simulate and evaluate long-term environmental effects.
• Fresnel reflectors: Special arrays of mirrors to focus sunlight in a manner that resembles a Fresnel lens in cross-section, enhancing irradiance.
• Exposure stages: Defined in terms of total solar radiant exposure or solar UV radiant exposure, allowing precise simulation of years of natural exposure in weeks or months.
• Apparatus requirements: Test devices, environmental controls, and specimen mounting techniques are referenced from related standards such as ASTM G90.
• Measurement parameters: Includes temperature, relative humidity, irradiance level, and water spray cycles, all of which are reported for comprehensive data collection.
• Testing under glass: Procedures for simulating weathering behind glass (e.g., for materials used in windows or automotive applications).
• Result documentation: Detailed protocols for recording test results, exposure cycles, environmental conditions, and any deviations from standard procedures.

Applications

The methods in ISO 877-3 are applicable to a wide range of industries where plastics are exposed to weathering:

• Automotive Components: Headlight lenses, exterior trims, and interior panels benefit from accelerated testing to predict appearance changes, embrittlement, and loss of mechanical properties.
• Construction Materials: Siding, roofing, pipes, and insulation materials can be evaluated for weather resistance and lifetime performance.
• Outdoor Products: Playground equipment, garden furniture, and protective coatings are subjected to rigorous weathering simulations.
• Packaging: Ensures that plastic containers, films, and wraps retain their critical properties when exposed to sunlight over time.
• Research and Development: Material scientists and product developers use these methods to compare formulations and innovate for enhanced durability.

Related Standards

Testing according to SIST EN ISO 877-3:2026 often involves cross-referencing and compliance with other internationally recognized standards, including:

• ISO 877-1: General guidance on methods of exposure to solar radiation for plastics.
• ISO 877-2: Direct weathering and exposure tests behind window glass.
• ISO 4892-1: General guidance on laboratory methods for exposing plastics to light sources.
• ASTM G90: Procedures for accelerated outdoor weathering using concentrated sunlight.
• ASTM G179: Specifications for temperature devices in natural weathering tests.
• ISO 4582: Methods for determining changes in color and properties after exposure.
• ISO 9370: Guidance on instrumental determination of radiant exposure in weathering tests.

By adhering to these standards, organizations ensure that results are consistent, reliable, and internationally recognized. This accelerates product development cycles and validates the weathering performance of plastic materials for demanding end-use environments.

Keywords: accelerated weathering, plastics, solar radiation, Fresnel reflectors, outdoor exposure testing, concentrated sunlight, ISO 877-3, plastic durability, test methods, weather resistance.