Do not rely on worn-out photocopies or outdated revisions. Purchase the official PDF from ASTM International, save it to your laboratory’s quality server, and build your conditioning protocols directly from the source. Your test results—and your reputation—depend on it. Prices and standard statuses are subject to change. Always verify the current revision at www.astm.org. This article is for informational purposes and does not constitute legal or accreditation advice.
A: Yes, except for tests where the standard test method (e.g., ASTM D638 for tensile) specifies a different condition. astm d618-21 pdf
For laboratory managers, quality engineers, and technicians searching for the , you are not just looking for a file—you are looking for the key to reproducible test results. This article explains everything you need to know about the standard, why the 2021 revision matters, and how to obtain a legitimate copy of the document. What is ASTM D618-21? ASTM D618-21 is the standard practice for conditioning plastics for testing. Officially titled "Standard Practice for Conditioning Plastics for Testing," this document establishes uniform environments (temperature and relative humidity) and time periods that plastic specimens must be exposed to before mechanical, electrical, or optical testing. Do not rely on worn-out photocopies or outdated revisions
A: Use: "Conditioned per ASTM D618-21, Cycle A (23°C ± 2°C / 50% RH ± 5%) for 72 hours." Prices and standard statuses are subject to change
| Feature | ASTM D618-21 | ISO 291 | | :--- | :--- | :--- | | Standard Temp | 23°C ± 2°C | 23°C ± 2°C | | Standard RH | 50% ± 5% | 50% ± 10% (looser) | | Conditioning Time | 40 hours min | 88 hours (for most materials) | | Test Time Limit | Immediate | Within 15 minutes |
The "21" denotes the year of last approval—2021. While the standard is reaffirmed periodically, the 2021 version currently contains the most up-to-date requirements for humidity control, temperature tolerances, and testing timelines. Plastics are hygroscopic or hydrophobic to varying degrees. Nylon absorbs moisture from the air, becoming more flexible and impact-resistant. Polycarbonate, on the other hand, can become brittle if too dry. Without a standard like ASTM D618, one laboratory might test "dry-as-molded" nylon while another tests nylon conditioned at 50% RH. The results would disagree by 50% or more.