False. ASTM D618-21 explicitly covers electrical, optical, and even thermal testing.

That night she dreamed in numbers: 23 ± 2°C, 50 ± 5% relative humidity, twelve hours, twenty-four hours — the standard’s rhythm. When she woke, she wrote them on index cards and pinned them above the bench like prayer flags. Practicality and reverence twined: she would run a series of validation runs to match these provisional conditions to her instruments.

This pragmatic approach makes the standard usable for general purchase specifications and product control tests, where consistency and speed are essential.

If you are looking for specific, in-depth technical details from the standard, the official ASTM D618-21 PDF is the definitive source.

Because the physical, electrical, and mechanical properties of plastics are highly sensitive to temperature and moisture, failing to condition specimens correctly can lead to inaccurate test results, product failures, and compliance issues. What is ASTM D618-21?