Overview
EN ISO 4918:2021 (ISO 4918:2016, incl. Amd 1:2018) specifies the castor chair test for resilient, textile and laminate floor coverings. The standard defines laboratory methods to determine changes in appearance, colour and structural stability - including detachment of layers, opening of joints or crazing - caused by the repetitive movement of a castor chair. EN ISO 4918:2021 is the CEN-adopted version of ISO 4918 and supersedes EN 425:2002.
Key topics and technical requirements
- Scope: Test procedures for textile, resilient and laminate floor coverings to assess appearance retention, colour change and structural damage under castor movement.
- Test principle: A specimen is subjected to a prescribed number of castor cycles using three castors moving in epicyclical paths with starts, stops and direction changes.
- Specified cycle counts (textile):
- Test A (appearance): assessment after 5 000 and 25 000 cycles (per ISO 9405).
- Test B (colour change): assessment after 750 cycles using grey scales.
- Test C (deterioration): assessment after 10 000 or 25 000 cycles.
- Resilient & laminate assessment: Focus on detachment of layers, opening of joints or crazing; specific criteria for click-joint floating installations are included.
- Apparatus details: Typical bench includes a rotating test platform (minimum 800 mm diameter), a castor assembly offset and three castors mounted at 120° intervals; tested area approx. 0.3 m². Loading and castor verification procedures are specified.
- Conditioning, sampling and mounting: Separate requirements for textile versus resilient/laminate specimens; conditioning per ISO atmospheres (e.g., ISO 139).
- Assessment & reporting: Defined assessment methods, calculations and mandatory elements for the test report.
Applications and who uses it
- Flooring manufacturers use EN ISO 4918 to validate product durability against office-chair traffic and to support product claims.
- Independent test laboratories apply the standard to provide accredited castor-chair test results.
- Specifiers, architects and facility managers use test data to select suitable floor coverings for offices, public spaces and contract environments.
- Procurement and quality assurance teams reference the standard when writing performance specifications or acceptance criteria.
Keywords: castor chair test, EN ISO 4918:2021, ISO 4918, floor coverings test, resilient floor coverings, textile floor coverings, laminate floor coverings, appearance retention, castor cycles.
Related standards
- ISO 9405 - Assessment of changes in appearance (referenced for Test A)
- ISO 139 - Standard atmospheres for conditioning and testing
- ISO 1957 - Selection and cutting of specimens
- ISO 2424 - Textile floor coverings - Vocabulary
- EN 12466 - Resilient floor coverings - Vocabulary
- CEN/TS 16354 - Laminate underlays - requirements and test methods
For manufacturers, test labs and specifiers seeking to evaluate castor resistance and product longevity, EN ISO 4918:2021 provides the harmonized, repeatable method for comparative and compliance testing.
