Overview
EN ISO 1522:2022 - Paints and varnishes - Pendulum damping test (ISO 1522:2022) specifies two standardized methods for measuring the damping behaviour of coating films using pendulum instruments. The test gives an indication of the surface “hardness” (resistance to deformation) of single-coat and multicoat paint and varnish systems by recording how quickly the amplitude of a pendulum oscillation is reduced when contacting the coated surface.
This European adoption (CEN) of ISO 1522:2022 supersedes the 2006 edition and aligns test practice across laboratories and manufacturers.
Key topics and requirements
- Two pendulum methods: the standard defines procedures for the König and Persoz pendulums, which differ in geometry, mass and sensitivity. Only one pendulum type should be used within a measurement series.
- Apparatus and calibration: detailed apparatus requirements and calibration procedures are provided (normative Annexes for König and Persoz), including checks for deformation and instrument performance.
- Sampling and test panels: requirements reference preparation and conditioning of test panels, film thickness control and substrate considerations. The recommendation for metal or glass panels was removed to permit other substrates (e.g., plastics).
- Test procedure: steps for instrument calibration, ambient condition control (temperature, humidity, absence of draughts), and the determination of pendulum damping time are specified.
- Expression and precision of results: methods for reporting results and the standard’s precision data (repeatability and reproducibility limits) are included for both pendulum types.
- Environmental sensitivity: the standard highlights that damping times depend on viscoelastic properties, film thickness and substrate, and therefore require controlled test conditions.
Applications and users
This standard is practical for:
- Coatings manufacturers - quality control of formulation and production batches.
- Independent test laboratories - reproducible laboratory testing for specification compliance.
- R&D teams and formulators - comparing hardness-related performance across formulations and curing conditions.
- Specifiers and purchasers - including pendulum damping results in technical specifications and acceptance criteria.
- Certification and compliance bodies - harmonized method for inter-laboratory comparison.
Use cases include routine QC checks, evaluation of curing or aging effects, comparative product testing, and research into viscoelastic film behaviour.
Related standards
Normative references within EN ISO 1522:2022 include:
Keywords: EN ISO 1522:2022, pendulum damping test, paints and varnishes, König pendulum, Persoz pendulum, coating hardness, coatings testing, quality control.