ASTM D2126-25 PDF

Full title and description

ASTM D2126-25 — Standard Test Method for Response of Rigid Cellular Plastics to Thermal and Humid Aging. This test method specifies procedures for artificial thermal and humid exposure of rigid cellular (foam) plastics and for measuring resulting dimensional changes to assess relative dimensional stability under accelerated aging conditions.

Abstract

This standard (designation D2126-25) provides agreed exposure conditions and measurement procedures to evaluate how rigid cellular plastics respond to elevated temperature and humidity. The method is intended for comparative assessment, quality control, and specification verification rather than for direct prediction of full end‑use performance. It also notes equivalence in sampling and calculation to ISO 2796 in defined sections.

General information

• Status: Active (current ASTM designation D2126-25).
• Publication date: 2025 (current version D2126-25; ASTM store lists the active standard last updated Mar 12, 2025).
• Publisher: ASTM International.
• ICS / categories: 83.100 (cellular materials).
• Edition / version: D2126-25 (current active version).
• Number of pages: 3 pages (concise test method).

Scope

Specifies procedures for thermal and humid exposure of rigid cellular plastics; users (purchaser and supplier) select the exposure conditions to match intended applications. Includes a list of commonly used exposure conditions (see Table 1 in the standard) and states SI units as standard. The standard clarifies that results are suitable for comparing material stability and establishing acceptance criteria but are not adequate for predicting detailed end‑use performance or for engineering design calculations.

Key topics and requirements

• Purpose: evaluate dimensional change (shrinkage/expansion) of rigid cellular plastics after controlled thermal and humid exposure.
• Exposure conditions: the standard provides a range of recommended temperatures and relative humidity conditions from which users choose; common practice in industry uses severe exposures such as 70 °C / ~97% RH for accelerated comparison (examples shown in industry literature and related specifications).
• Specimen preparation and measurement: dimensional measurements are made before and after exposure (final measurements may be after return to room temperature unless otherwise specified).
• Intended use: comparative performance evaluation and stability acceptance criteria; not a direct predictor for all field conditions.
• Relationship to other documents: sampling/calculation sections noted equivalent to ISO 2796 (but procedure sections differ).

Typical use and users

Used by materials and product manufacturers (rigid foam insulation and other cellular plastics), independent testing laboratories, quality/acceptance engineers, specification writers, and regulatory or code bodies to document dimensional stability and to support product specifications, supplier verification, and comparative R&D screening. Laboratories offering D2126 testing also cite this method when reporting accelerated stability data.

Related standards

ISO 2796 (sampling and calculation equivalence in parts of the method), and various ASTM standards commonly referenced alongside D2126 in insulation and foam specifications (for example ASTM D1621, D1622, D2842 and other test methods for physical properties and water absorption). D2126 is also cited within material specifications and product standards that set dimensional‑change limits for spray polyurethane foam and board insulations.

Keywords

rigid cellular plastics; foam; thermal aging; humid aging; dimensional stability; accelerated aging; ASTM D2126-25; ISO 2796; dimensional change.

FAQ

Q: What is this standard?

A: ASTM D2126-25 is a standardized test method for assessing the response (primarily dimensional change) of rigid cellular plastics when exposed to elevated temperature and humidity under controlled, accelerated conditions.

Q: What does it cover?

A: It covers specimen preparation, recommended exposure conditions (a selectable set of temperature/humidity conditions), measurement procedures and calculation/sampling rules to report dimensional change; it emphasizes comparative assessment rather than predicting complete end‑use performance.

Q: Who typically uses it?

A: Manufacturers of rigid foam products, independent test laboratories, quality engineers, product specifiers, and bodies that write material or product specifications—anyone needing a repeatable method to compare dimensional stability under thermal and humid stress.

Q: Is it current or superseded?

A: The current active designation is D2126-25 (the 2025 revision). ASTM lists the standard as active and notes the active version was last updated on Mar 12, 2025.

Q: Is it part of a series?

A: D2126 is maintained by ASTM Committee D20 (Subcommittee D20.22) and has previous published versions (for example D2126‑20, D2126‑15, etc.); it is often used in combination with other ASTM tests for foam physical properties in product specifications.

Q: What are the key keywords?

A: Dimensional stability, thermal aging, humid aging, rigid cellular plastics, foam insulation, accelerated aging, ASTM D2126-25.