ASTM D618-21 defines several specific procedures (Procedures A through E) to simulate various service environments: Condition at Relative Humidity. Duration: 40 hours for thickness ≤is less than or equal to 7 mm, 88 hours for > 7 mm. Procedure B (Oven Conditioning): Conditioning in an oven at for 48 hours, followed by cooling in a desiccator.
is the definitive standard for the conditioning of plastic materials before they undergo mechanical, electrical, or thermal testing. Because the physical properties of plastics are highly sensitive to environmental factors, this practice ensures that test results are reproducible and comparable across different laboratories. astm d618-21 pdf