ISO 4892-3: Testing Methods for Plastic Weathering
ISO 4892-3 is an internationally-recognized test standard for exposing plastic specimens to fluorescent UV lamp radiation, heat, and water. This standard includes several different cycles intended to accelerate and simulate outdoor forces of weathering to test materials for physical property degradation and color change.
ISO 4892-3 was revised in 2024 to include new, high-irradiance test cycles and update language on temperature control that allows the use of insulated black panels.
Test Parameters
ISO 4892-3 includes a variety of different test cycles that vary in lamp type, irradiance level, temperature, and water delivery, allowing users to customize their cycle based on their testing goals, materials, and service environments.
Method A: UVA-340 lamps
UVA-340 lamps provide the most realistic simulation of the shortwave portion of natural outdoor sunlight. ISO 4892-3 features four primary cycles that use UVA-340 lamps.
- Cycle 1:
- Exposure period: 8 hour Light, 4 hour Condensation
- Irradiance: 0.76 W/m2/nm @ 340 nm
- Black panel temperature: 60 °C (Light); 50 °C (Condensation)
- Cycle 2:
- Exposure period: 8 hour Light, 0.25 hour Water Spray, 3.75 hour Condensation
- Irradiance: 0.76 W/m2/nm @ 340 nm
- Black panel temperature: 50 °C (Light and Condensation); not controlled in Spray step
- Cycle 3:
- Exposure period: 5 hour Light, 1 hour Water Spray
- Irradiance: 0.83 W/m2/nm @ 340 nm
- Black panel temperature: 50 °C (Light); not controlled in Spray step
- Cycle 4:
- Exposure period: 5 hour dry, 1 hour water spray
- Irradiance: 0.83 W/m2/nm @ 340 nm
- Black panel temperature: 70 °C (Light); not controlled in Spray step
Method B: UVA-351 lamps
UVA-351 lamps simulate shortwave UV from sunlight behind window glass, and can be used for materials in indoor environments. ISO 4892-3 has one cycle that uses UVA-351 lamps.
- Cycle 5:
- Exposure period: 24 hour Light (no moisture)
- Irradiance: 0.76 W/m2/nm @ 340 nm
- Black panel temperature: 50 °C
Method C: UVB-313 lamps
UVB-313 lamps deliver irradiance at wavelengths even shorter than those experienced on Earth's surface. This can accelerate degradation, making them good for quality control purposes, but can also produce failure modes not observed in real life. ISO 4892-3 includes two cycles for UVB-313 lamps, including the recently-added, higher-irradiance, Cycle 7.
- Cycle 6:
- Exposure period: 8 hour Light, 4 hour Condensation
- Irradiance: 0.48 W/m2/nm @ 310 nm
- Black panel temperature: 70 °C ± 3 °C (Light); 50 °C (Condensation)
- Cycle 7:
- Exposure period: 8 hour Light, 4 hour Condensation
- Irradiance: 0.71 W/m2/nm @ 310 nm
- Black panel temperature: 60 °C (Light); 50 °C (Condensation)
Method D: UVA-340 lamps with higher irradiance
UVA-340 lamps provide the most realistic simulation of the shortwave portion of natural outdoor sunlight. ISO 4892-3 was revised in 2024 to include two optional cycles for UVA-340 lamps, with higher "two sun" and "three sun" irradiance
- Cycle 8:
- Exposure period: 8 hour Light, 4 hour Condensation
- Irradiance: 1.36 W/m2/nm @ 340 nm
- Black panel temperature: 60 °C ± 3 °C (Light); 50 °C ± 3 °C (Condensation)
- Cycle 9:
- Exposure period: 8 hour Light, 4 hour Condensation
- Irradiance: 2.04 W/m2/nm @ 340 nm
- Black panel temperature: 60 °C ± 3 °C (Light); 50 °C ± 3 °C (Condensation)
Q-Lab customers can log in to their Q-Portal account for in-depth information regarding ISO 4892-3.
Why Test Using ISO 4892-3
ISO 4892-3 is iused widely to evaluate the weatherability performance of plastic materials. This testing method ensures that applications maintain functionality in outdoor conditions where materials are exposed to sunlight, heat, and moisture. Although the standard is maintained by the Plastics committee of ISO, the test cycles are used across many industries that perform UV fluorescent testing, including automotive and packaging, Very similar cycles are found in ISO 16474-3, which is designed for testing paints and coatings, which speaks to the broad applicability of these test conditions.
This internationally-recognized standard allows manufacturers to perform quality control testing, meet regulatory requirements, and guide R&D teams during product development, ultimately improving the overall longevity and quality of their product.
Pros and Cons of ISO 4892-3
- Great for comparative testing of materials for UV degradation
- The test methods used in ISO 4892-3 often provide strong correlation with material failures experienced in natural outdoor environments
- Use of hot condensation
- ISO 4892-3 delivers continuously reforming condensation at elevated temperatures, providing the most realistic way to accelerate moisture attack
- Variety of lamps defined in test cycles to meet individual testing needs
- Depending on the material or application you are testing, ISO 4892-3 recommends test conditions using various lamp types to meet your particular test goals
- New, higher-irradiance optional cycles can accelerate testing even further
- For materials primarily sensitive to light, higher-irradiance conditions can effectily shorten material test times
- Realism of testing
- The added shortwave of UVB lamps in Method C and very high irradiances in Method D can reduce test times, but also may cause some polymers to degrade differently than they would outdoors
- The lack of full-spectrum sunlight, as with any UV fluorescent testing, may not reproduce all color change effects
- Excess water spray
- Water spray periods of up to 1 hour are longer than necessary for thermal shock effects, and less effective than hot condensation
How Q-Lab Can Help
QUV Accelerated Weathering Tester
Q-Lab’s QUV accelerated weathering tester fully complies with ISO 4892-3. It is the simplest, most reliable, and easiest-to-use weathering tester available. With thousands of testers in use worldwide, it is the world's most widely-used weathering tester.
Testing Services
If a new tester is not part of the budget, we offer contract testing at either of our two accelerated testing laboratories – Florida or Germany. Both labs are ISO 17025 accredited to perform ISO 4892-3, using the very same QUV test chambers built at our manufacturing plant. In addition to accredited testing, our laboratories are qualified to perform a suite of different evaluations, including color change, gloss retention, tensile hardness, and much more.
More ISO 4892-3 Resources
Standards Tool
Review setup and performance information on key international and OEM test standards from ASTM, ISO, SAE, JIS, GB, and more.
Document Library
Browse Q-Lab’s extensive library of weathering testing literature and technical content.
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