ISO 4628-10-2024 PDF

Full title and description

St ISO 4628-10-2024 — Paints and varnishes — Evaluation of quantity and size of defects, and of intensity of uniform changes in appearance — Part 10: Assessment of degree of filiform corrosion. This international standard specifies procedures to assess the amount and severity of filiform corrosion developing from a scribed mark on coated substrates, using measured filament lengths and pictorial examples to support rating consistency.

Abstract

ISO 4628-10:2024 defines methods for assessing filiform corrosion by measuring the length of the longest filament (L) and the most frequent filament length (M) on a test panel, and by comparing results to illustrative photographs in Annex A. The pictorial examples are informative but do not replace the mandatory numerical assessment (method 1 or method 2) described in the standard. The document is part of the ISO 4628 family, which provides a uniform designation system for coating defects and uniform appearance changes.

General information

• Status: Published (International Standard).
• Publication date: March 2024 (official publication March 2024; various national catalogues list availability from 15 March 2024).
• Publisher: International Organization for Standardization (ISO), technical committee ISO/TC 35/SC 9 (Paints and varnishes).
• ICS / categories: 87.040 (Paints and varnishes).
• Edition / version: Edition 3 (2024), replaces ISO 4628-10:2016.
• Number of pages: 8 pages (ISO published technical text).

Scope

This part of ISO 4628 specifies a method to assess the degree of filiform corrosion that develops from a scribe (artificial defect) in organic coatings on metallic substrates. The standard provides numerical measurement procedures (methods 1 and 2) based on filament length (L and M) and includes pictorial reference images (Annex A) to help with visual grading. ISO 4628-10 is intended to be used together with ISO 4628-1, which defines the general designation system for defect quantity, size and intensity of uniform appearance changes.

Key topics and requirements

• Definition and measurement of the longest filament length (L) and the most frequent filament length (M) for filiform corrosion assessment.
• Two mandatory numerical assessment methods (method 1 and method 2) for reporting filiform corrosion severity.
• Annex A pictorial grading set (12 photographic examples) to illustrate rating classes — illustrative only and not a substitute for numerical measurement.
• Application of the ISO 4628 general designation system (ISO 4628-1) for expressing results in a consistent format.
• Requirements for test-panel preparation, scribing procedure and measurement conditions as necessary to ensure reproducible results (see normative clauses).

Typical use and users

Used by coating manufacturers, corrosion-test laboratories, quality assurance and R&D teams, specification writers, asset owners and consultants who evaluate coating performance against filiform corrosion. Typical applications include performance testing of anticorrosive coatings, acceptance testing after accelerated or natural exposure, comparative lab studies, and contract/specification compliance checks.

Related standards

ISO 4628 is a multipart series; related parts include ISO 4628-1 (general introduction and designation system), ISO 4628-2 (blistering), ISO 4628-3 (rusting), ISO 4628-4 (cracking), ISO 4628-5 (flaking/peeling), ISO 4628-6/7 (chalking), ISO 4628-8 (delamination and corrosion around a scribe) and other parts addressing specific defect types. Users routinely apply ISO 4628-10 together with ISO 4628-1 and relevant test/exposure standards (for example salt-spray or cyclic corrosion tests) when assessing coating durability.

Keywords

Filiform corrosion, coatings, paints and varnishes, evaluation, defect designation, filament length, L and M measurements, scribed mark, coating degradation, ISO 4628, visual grading, Annex A.

FAQ

Q: What is this standard?

A: ISO 4628-10:2024 is the part of the ISO 4628 series that specifies methods to assess the degree of filiform corrosion on coated substrates, using measured filament lengths and illustrative images to support grading.

Q: What does it cover?

A: It covers procedures to measure the length of filiform corrosion filaments originating from a scribe (longest filament L and most frequent filament length M), two numerical assessment methods (methods 1 and 2), and an Annex with pictorial examples to aid interpretation. The pictorial examples do not replace the mandatory numerical assessment.

Q: Who typically uses it?

A: Coating manufacturers, independent test laboratories, R&D and QA personnel, specifiers and engineers involved in durability testing and acceptance of protective and decorative coatings use this standard to report and compare filiform corrosion results consistently.

Q: Is it current or superseded?

A: Current — ISO 4628-10:2024 (Edition 3, published March 2024) supersedes ISO 4628-10:2016 (the 2016 edition was withdrawn when the 2024 edition was published).

Q: Is it part of a series?

A: Yes — it is Part 10 of the multipart ISO 4628 series (evaluation of degradation of coatings). The series provides a harmonized system (defined in ISO 4628-1) for designating defect type, quantity, size and intensity of uniform appearance changes across multiple defect types.

Q: What are the key keywords?

A: Filiform corrosion; filament length (L, M); scribed mark; coating defects; visual grading; numerical assessment; ISO 4628; paints and varnishes; coating durability.