EN ISO 3385:2014 PDF

Overview

EN ISO 3385:2014 (ISO 3385:2014) defines a laboratory method - constant-load pounding - for assessing fatigue of flexible cellular polymeric materials (notably polyurethane and rubber-latex foams) used in load-bearing upholstery. The standard specifies how to measure loss in thickness and loss in hardness after repeated indentation cycles, helping characterize foam performance under simulated service loading. It applies to both slabstock test pieces and shaped components and is adopted by CEN as EN ISO 3385:2014.

Key topics and technical requirements

• Measured properties: Loss in thickness and loss in hardness (results are indicative of service performance but not necessarily identical to in-service losses).
• Test principle: Repeated indentation (pounding) using an indentor smaller than the test piece; maximum load each cycle controlled within specified limits.
• Apparatus types:
  • Type A: Simple crank/suspended-weight mechanism where full force acts for ≤10% of each cycle.
  • Type B: Fully controlled electro-mechanical, pneumatic or hydraulic machine with load cell and automatic control; force measurement precision ±1%.
• Indentor and platen details: Indentor diameter 250 mm ±1 mm with a 25 mm ±1 mm lower-radius edge; maximum force 750 N ±20 N; platen should be vented (≈6 mm holes at ~20 mm pitch) to allow air escape.
• Operational parameters: Stroke rate 70 ±5 strokes/min; indentor peak force applied for no more than ~10% of cycle. For Type B machines, peak force must be maintained within tolerance throughout the test.
• Test pieces & conditioning: Standard test piece dimensions 380 mm ±20 mm sides, thickness 50 mm ±2 mm; three specimens tested; conditioning requirements include waiting at least 72 h after manufacture and conditioning for ≥16 h at specified temperature/humidity (23±2 °C / 50%±5% RH or 27±2 °C / 65%±5% RH).
• Referenced standard: ISO 2439 (hardness - indentation technique) is normatively referenced.

Applications and users

Who benefits:

• Foam and rubber-latex manufacturers for product development and quality control
• Testing laboratories performing performance and comparative fatigue tests
• Furniture and upholstery manufacturers specifying load-bearing foam performance
• Procurement/specification writers requiring comparative data for supplier evaluation
• R&D teams comparing formulations, processing or aging effects

Practical uses:

• Benchmarking foam formulations for durability in seating and cushioning
• Routine QC to detect batches with poor fatigue resistance
• Comparative testing of shaped components and slabstock used in upholstery

Related standards

• ISO 2439: Flexible cellular polymeric materials - Determination of hardness (indentation technique) - normatively referenced.
• EN ISO 3385:2014: European adoption of ISO 3385:2014.

This standard provides a repeatable laboratory method to assess pounding-induced fatigue in upholstery foams, supporting product development, QC and procurement decisions related to foam durability.