Step-by-step guides for conditioning specimens at standard atmospheres, in desiccators, or at elevated temperatures. It also outlines how to determine when "equilibrium" has been reached (typically when consecutive weight differences are less than 0.1%).
Plastics experience internal stresses during molding or extrusion. Controlled conditioning allows the polymer chains to relax, ensuring the test reflects the material's true properties rather than processing anomalies. Core Conditioning Procedures in ASTM D618-21
Lists companion standards, including ASTM E41 (Terminology Relating to Conditioning) and ISO 291.
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