Overview
EN ISO 19397:2024 (ISO 19397:2024) defines a standardized method for determining the film thickness of coatings using an ultrasonic gauge. The method applies to coatings on metallic and non‑metallic substrates and replaces ISO/TS 19397:2015 and supersedes CEN ISO/TS 19397:2018. The European adoption (EN ISO 19397:2024) was approved in November 2024 and is to be implemented as a national standard by CEN members.
Key Topics and Requirements
- Scope and purpose: Measurement of coating film thickness by ultrasonic pulse-echo techniques on diverse substrates.
- Principle and physical background: Use of ultrasonic waves (longitudinal/compressional) and echo detection; interpretation of A‑scan presentations and echo signals.
- Apparatus and materials:
- Ultrasonic film thickness measuring device (probe/sensor, electronics).
- Couplant (medium such as water, glycerine or oil) to enable acoustic coupling.
- Calibration standards for setting up and validating the instrument.
- Calibration, adjustment and verification: Procedures to calibrate and adjust the gauge and to check ongoing accuracy before and during measurement campaigns.
- Measurement procedure: Steps for performing film thickness readings, including handling multi‑layer systems (coating numbering convention).
- Environmental factors: Consideration of temperature influence during measurement.
- Precision and metrology:
- Requirements and reporting for repeatability and reproducibility limits.
- References to metrology concepts and uncertainty (ISO Guide 99).
- Reporting: Mandatory content for the test report to ensure traceability and reproducibility.
- Informative annexes: Guidance on personnel competence and methods for determination of precision.
Applications and Who Uses It
EN ISO 19397 is intended for:
- Quality control laboratories and production QA in paint, varnish and coatings manufacturing.
- Field inspectors and maintenance teams assessing protective coatings on structures (steelwork, pipelines, infrastructure, marine vessels).
- R&D teams validating coating application and multi‑layer systems.
- Specification writers and certification bodies needing a harmonized, repeatable non‑destructive film thickness method.
Practical benefits include non‑destructive inspection, improved traceability of coating application, compliance with procurement/specification requirements, and consistent data for corrosion protection assessments.
Related Standards
- ISO 4618 (paints and varnishes vocabulary) - referenced for terminology.
- ISO Guide 99 (VIM) - metrology vocabulary and measurement uncertainty.
- ISO/TS 19397:2015 (withdrawn) and ISO 2808 (noted for alternate coating enumeration conventions).
Keywords: EN ISO 19397:2024, ISO 19397, ultrasonic gauge, film thickness measurement, paints and varnishes, coating inspection, calibration, couplant, A‑scan, repeatability, reproducibility.