Overview
EN ISO 6270-2:2025 - "Paints and varnishes - Determination of resistance to humidity - Part 2: Condensation (in-cabinet exposure with heated water reservoir)" - defines reproducible test conditions and procedures for exposing coated test specimens to condensation-water atmospheres inside a climatic cabinet with a heated water reservoir. The standard establishes how to create constant or alternating condensation atmospheres so results from different laboratories are comparable. It does not cover specimen shape, preparation, test duration or result assessment.
Key topics and requirements
- Test atmospheres (designation):
- CH - Condensation with constant humidity
- AHT - Alternating humidity and air temperature
- AT - Alternating air temperature
- IC - Intermittent condensation (newly included from ISO 11503)
- Apparatus and setup: requirements for a climatic chamber, installation, and a heated water reservoir; devices for accommodating specimens and ensuring chamber ventilation and loading are appropriate.
- Procedure elements: start-up, specimen arrangement and spacing (now recommendations rather than strict requirements), filling of floor trough, verification of condensation formation (simplified procedure included), defined test sequences (CH, AHT, AT, IC), permitted interruptions and end-of-test handling.
- Evaluation and precision: guidance on recording conditions and reporting to support reproducibility between laboratories; normative references and annex for condensation-water comparison quantity.
- Normative references and terminology: references include ISO 3270 (conditioning temperatures/humidities) and ISO 4618 (vocabulary).
Practical applications
- Assessing humidity resistance of coatings and varnishes used on metal, wood and other substrates.
- Quality control and batch verification in paint manufacturing.
- Comparative performance testing during product development and R&D.
- Supporting claims for corrosion protection and environmental durability.
- Providing standardized conditioning prior to further evaluation (e.g., visual assessment using ISO 4628 series or contract-specific assessment methods).
Who should use this standard
- Coating and paint manufacturers (quality, R&D, product development).
- Independent testing and certification laboratories performing humidity/condensation tests.
- OEMs and specifiers who require validated humidity-resistance data for material selection.
- Regulatory bodies and procurement teams needing harmonized test methods for tendering and compliance.
Related standards
- ISO 3270 - Conditioning temperatures and humidities for paints and varnishes
- ISO 4618 - Paints and varnishes - Vocabulary
- ISO 4628 series - Examples of visual evaluation methods (assessment methods often used after conditioning)
Keywords: EN ISO 6270-2:2025, resistance to humidity, condensation test, in-cabinet exposure, heated water reservoir, paints and varnishes testing, climatic chamber, humidity resistance testing, intermittent condensation.
