ASTM C1908-21 (2025) PDF

Full title and description

ASTM C1908-21 (reapproved/confirmed 2025) — Standard Test Method for Pummel Adhesion Testing of Two‑ply Laminated Architectural Glass. This qualitative test method describes manual and semi‑automatic pummel procedures and a visual rating system to assess the relative adhesion between an interlayer and glass substrates (including inks, coatings, frits and other surface treatments) for two‑ply laminated architectural glass.

Abstract

This standard defines a pummel adhesion test used to evaluate the relative bond strength at the interlayer‑to‑glass (or interlayer‑to‑coating/ink/frit) interface for two‑ply laminated architectural glass. The method produces a qualitative pummel rating (for example: high, medium, low, or zero adhesion) based on controlled impact of a hammer or automated pummeling device and visual inspection of post‑failure residue and glass fragmentation. It is intended for production control, comparison of interlayer systems, and assessment of likely post‑breakage behavior but is not a precision, quantitative adhesion test.

General information

• Status: Active (current edition designated C1908‑21; reapproved/confirmed 2025).
• Publication date: Original edition approved Sept 1, 2021 and published in 2021; reapproval/confirmation issued in 2025 (designation shown as C1908‑21(2025)).
• Publisher: ASTM International (American Society for Testing and Materials).
• ICS / categories: 81.040.20 — Glass in building (Laminated glass testing and evaluation).
• Edition / version: Designation C1908‑21 (current edition); referenced as C1908‑21(2025) where reapproval year is indicated.
• Number of pages: 12 pages (standard length for the test method document).

Scope

Defines a qualitative test method to determine the relative strength of the adhesive bond between interlayers and glass substrates (and surface treatments such as inks, frits, coatings or low‑E layers) in two‑ply laminated architectural glass. Applicable to flat and patterned, annealed or heat‑treated glass, decorated or undecorated surfaces. The method covers specimen preparation, pummeling procedure (manual or semi‑automatic), containment and lighting for inspection, and a visual rating scale for post‑pummel residue and glass retention. It is not intended to provide numerical precision for adhesion strength but to provide comparative grading and production control information.

Key topics and requirements

• Definition of specimen types and permitted surface conditions (coatings, inks, frits, tempered/annealed).
• Manual and semi‑automatic mechanical pummeling procedures (hammer type, impact location, number of impacts, and specimen fixturing).
• Construction and use of a pummel box (containment, lighting, and backer panel for visual evaluation).
• Visual pummel rating system with qualitative grades (for example: high, medium, low, zero adhesion) and criteria for assigning ratings based on retained glass vs. interlayer exposure.
• Guidance on safety, sample handling, and documentation of test conditions and observations.
• Notes on applicability and limitations — method for relative comparison rather than absolute bond‑strength measurement.

Typical use and users

Used by laminated glass manufacturers, interlayer material suppliers, quality control and testing laboratories, façade and architectural glazing specifiers, and research groups assessing laminate durability and post‑breakage behavior. Typical uses include production quality checks, comparative evaluation of interlayer formulations, acceptance testing for coated or printed glass interfaces, and investigation of delamination or impact performance issues.

Related standards

Standards commonly referenced alongside or relevant to C1908 include ASTM C1172 (Specification for Laminated Architectural Flat Glass), ASTM C162 (Terminology of Glass and Glass Products), ASTM C1914 (Bake and Boil Testing of Laminated Glass), EN 14449 (lami­nated glass product standard/evaluation), and ISO standards on laminated glass (for example ISO 12543 series). These provide complementary definitions, product specifications and additional test methods for laminated glass performance and durability.

Keywords

pummel test, pummel adhesion, laminated glass, two‑ply laminate, interlayer adhesion, glass substrate, visual rating, pummel box, quality control, architectural glazing

FAQ

Q: What is this standard?

A: ASTM C1908‑21 is a test method that describes how to perform pummel adhesion testing to qualitatively assess the bond between an interlayer and the glass (or coated/printed surfaces) in two‑ply laminated architectural glass.

Q: What does it cover?

A: It covers specimen preparation, manual and semi‑automatic pummeling procedures, containment and lighting for inspection, and a visual rating scheme to grade the amount of glass retained versus exposed interlayer or coating after pummeling. It is intended for comparative and production control purposes rather than absolute bond‑strength measurement.

Q: Who typically uses it?

A: Manufacturers of laminated glass and interlayers, testing laboratories, façade engineers, product specifiers, and quality managers use this standard to compare interlayer adhesion and to monitor production consistency.

Q: Is it current or superseded?

A: The designation is C1908‑21 (indicating approval in 2021). The document has been reapproved/confirmed in 2025 (often shown as C1908‑21(2025)) and is treated as current/active for use; check with ASTM International for the most recent confirmation or revisions if precise status is required for procurement or regulatory citation.

Q: Is it part of a series?

A: It is a single ASTM test method under Committee C14 (Glass and Glass Products). It is commonly used with related ASTM specifications and methods for laminated glass (for example ASTM C1172 and ASTM C1914) and complements regional product standards such as EN 14449 and ISO laminated glass standards.

Q: What are the key keywords?

A: Pummel adhesion, laminated glass, interlayer adhesion, two‑ply laminate, pummel box, visual rating, glass substrate, adhesion testing.