Overview
ASTM G113-22: Standard Terminology Relating to Natural and Artificial Weathering Tests of Nonmetallic Materials provides universally recognized definitions and clarifies terminology used in the durability testing of nonmetallic materials. Developed by ASTM Committee G03 on Weathering and Durability, this standard ensures consistency and clarity in describing natural and artificial weathering testing methods and conditions. The terminology is widely referenced by manufacturers, laboratories, and standards organizations engaged in evaluating material performance against weathering-induced degradation.
Key Topics
ASTM G113-22 covers essential concepts and vocabulary to support reliable communication and reporting in weathering tests, including:
- Accelerated and Natural Weathering: Defining laboratory-simulated (artificial) vs. real-world outdoor (natural) weathering test methods and the conditions under which they are performed.
- Exposure and Instrumentation: Terms describing specimen orientation, exposure angles, irradiance, and the use of devices such as black box enclosures and black panel thermometers.
- Environmental Parameters: Clarifying measures of ambient temperature, relative humidity, time-of-wetness, and illumination characteristics (UV, visible, and IR solar irradiance).
- Material and Test Definitions: Standardizing distinctions between specimens, controls, reference materials, and weathering reference material (WRM).
- Measurement Uncertainty: Acknowledging the importance of quantifying and reporting uncertainties in measurements of environmental variables and material responses.
- Specific Testing Terms: Including detailed definitions for concepts such as photodegradation, solar azimuth angles, fading units, and operational control points in exposure devices.
ASTM G113-22 does not replace similar definitions in other standards but draws together terms in widespread use within ASTM’s weathering and durability standards.
Applications
The standardized terminology in ASTM G113-22 is essential for:
- Material Testing Laboratories: Ensuring clear, consistent protocols for natural and artificial weathering testing of plastics, coatings, textiles, and construction materials.
- Product Development: Supporting engineers and designers in the evaluation of new nonmetallic materials by enabling accurate interpretation and comparison of weathering test data.
- Quality Assurance: Assisting manufacturers in documenting and verifying durability claims for products subjected to environmental exposure, from outdoor appliances to automotive components.
- Standards Harmonization: Providing common language for international and cross-industry technical documents, supporting trade and regulatory compliance per WTO Technical Barriers to Trade (TBT) Committee guidelines.
- Research and Reporting: Facilitating reproducibility in scientific studies on weathering effects by establishing a shared set of definitions for environmental parameters and degradation mechanisms.
Related Standards
ASTM G113-22 references and complements a network of related standards to support comprehensive weathering testing:
- ASTM D9: Terminology Relating to Wood and Wood-Based Products
- ASTM E41 & E772: Terminology for conditioning and solar energy conversion
- ASTM G84, G90, G201: Practices for time-of-wetness measurement, accelerated outdoor weathering, and outdoor glass-covered exposure
- AATCC Method 16: Colorfastness to Light testing
- ANSI/NCSL Z540-2: Guidelines for measurement uncertainty
- ISO 9370: Guidance on measuring radiant exposure in weathering tests
- CIE 17.4: International Lighting Vocabulary
- Guide to the Expression of Uncertainty Measurement (GUM): Uncertainty assessment in measurements
Organizations and professionals working in durability assessment, product certification, and R&D will find ASTM G113-22 an indispensable reference for precise, internationally accepted terminology in the field of nonmetallic materials weathering tests.