ASTM C1785-24 PDF

Full title and description

ASTM C1785-24 — Standard Test Method for Concentration of Pinhole Detections in Moisture Barriers on Metal Jacketing. This test method defines a procedure to detect and quantify pinholes (holiday defects) in moisture-barrier films or coatings applied to the interior face of electrically conductive metal jacketing used with thermal insulation systems.

Abstract

This standard specifies an electrical detection technique for locating and counting pinholes in nonconductive moisture-barrier films or coatings that are applied to conductive metal jacketing. The method depends on completion of an electrical circuit through the jacketing and is therefore applicable only when the metal jacketing is electrically conductive and the barrier is nonconductive. Results are reported as concentration of pinhole detections per unit area; inch‑pound units are the standard.

General information

• Status: Active.
• Publication date: September 1, 2024 (designation C1785-24).
• Publisher: ASTM International.
• ICS / categories: 29.035.01 (Insulating materials in general); 91.100.60 (Thermal and sound insulating materials).
• Edition / version: C1785-24 (2024).
• Number of pages: 6.

Scope

The standard covers determination of the concentration of pinhole detections in a moisture‑barrier film or coating applied to the interior surface of metal jacketing. Because the method requires electrical continuity through the metal jacketing, it applies only to electrically conductive jacketing with a nonconductive moisture barrier. The procedure includes guidance on test setup, area measurement, detection, counting, and reporting of pinhole concentration; customary inch‑pound units are primary.

Key topics and requirements

• Principle: electrical holiday/pinhole detection by completing a circuit through conductive jacketing to locate barrier defects.
• Sample preparation and defined test area measurement to report concentration as defects per unit area.
• Instrumentation and test parameters (high‑voltage detector settings, probe technique and grounding) necessary to reliably locate pinholes.
• Counting and calculation rules for converting detection events to a concentration metric (number per unit area) and reporting conventions.
• Limitations and applicability: only for conductive jacketing with nonconductive barriers; safety precautions for high‑voltage testing are required.
• Precision summary available from an interlaboratory study (Research Report RR:C16‑1048) that supports the method’s precision statement.

Typical use and users

Used by materials and coatings manufacturers, insulation and jacketing producers, independent testing laboratories, quality‑control/assurance personnel, inspection agencies, and engineers/specifiers involved in thermal insulation systems to verify integrity of moisture‑barrier films and to quantify pinhole concentrations for acceptance criteria and product development.

Related standards

Commonly referenced or used alongside other ASTM C16 committee documents and jacketing/insulation standards, for example ASTM C1729 (aluminum jacketing), ASTM C1767 (stainless steel jacketing), ASTM C1775 (laminate protective jacket and tape), and guidance such as ASTM C1423 (selecting jacketing materials for thermal insulation), among others. These related documents address jacketing materials, installation, and complementary test methods.

Keywords

pinhole, holiday detection, moisture barrier, metal jacketing, jacketing, cladding, lagging, moisture retarder, thermal insulation, concentration, electrical detection, C1785.

FAQ

Q: What is this standard?

A: ASTM C1785-24 is a standardized test method for detecting and quantifying pinholes (holiday defects) in moisture‑barrier films or coatings applied to the interior surface of electrically conductive metal jacketing.

Q: What does it cover?

A: It covers the electrical detection technique, test setup, instrument considerations, counting and reporting of pinhole concentration (defects per unit area), and notes applicability limits (conductive jacketing with nonconductive barrier).

Q: Who typically uses it?

A: Manufacturers of jacketing and moisture barriers, independent test laboratories, insulation contractors, quality assurance/inspectors, and engineers/specifiers use the method for product verification and acceptance testing.

Q: Is it current or superseded?

A: The C1785-24 edition is the current active designation (2024 edition) as published by ASTM International.

Q: Is it part of a series?

A: It is part of the ASTM C16 committee’s body of standards covering thermal insulation and jacketing systems; it is commonly used with related C16 standards addressing jacketing specifications and selection (for example C1729, C1767, C1775, C1423).

Q: What are the key keywords?

A: Pinhole, holiday detection, moisture barrier, metal jacketing, jacketing, insulation, concentration, electrical detection.