Pdf | Astm D618-21

A: The 2021 revision tightens humidity tolerances, clarifies test time limits, and updates referenced standards.

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. astm d618-21 pdf

A: For Cycle A (standard), a minimum of 40 hours, but moisture equilibrium may take longer (e.g., 4 days for thick nylon bars). A: The 2021 revision tightens humidity tolerances, clarifies

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. Plastics are hygroscopic or hydrophobic to varying degrees

ISO 291 is more forgiving on humidity tolerance but requires longer conditioning. ASTM D618-21 is stricter on RH but shorter on time. Never assume compliance with one means compliance with the other. 10 Frequently Asked Questions (FAQ) Q1: Can I get ASTM D618-21 for free? A: Not legally unless your employer subscribes to ASTM Compass or you have academic access.

Accreditation bodies (A2LA, UKAS, NABL) now reference D618-21. If your quality manual says "D618-13," you are non-conforming. Comparing ASTM D618-21 to ISO 291 If you work globally, you may know ISO 291:2008 ( Plastics – Standard atmospheres for conditioning and testing ). The two are technically harmonized but not identical.