Conditioning is rarely about reaching "perfect" equilibrium, as some plastics might require 20 to 100 days to fully stabilize. Instead, ASTM D618-21 provides a practical framework to:
The "21" in the designation indicates that the most recent major revision was approved in . You can view or purchase the official document at the ASTM International website or through authorized distributors like the ANSI Webstore and Accuris Standards Store . Core Significance and Purpose astm d61821 pdf
: Variations are strictly limited. For example, if a temperature tolerance of is required, the humidity tolerance must be within Core Significance and Purpose : Variations are strictly
The standard outlines several specific procedures (A through E) tailored to different material types and testing requirements. Conditioning Environment Primary Use Case 40 hours ( thick) or 88 hours ( Standard laboratory atmosphere for general testing. Procedure B in an oven 48 hours, followed by cooling in a desiccator Accelerated drying and thermal conditioning. Procedure C distilled water Procedure B in an oven 48 hours, followed
: Predict how a material will perform under specific "abnormal" conditions, such as extreme heat or high humidity.