Overview
EN ISO 8307:2018 - "Flexible cellular polymeric materials - Determination of resilience by ball rebound" is a CEN-endorsed adoption of ISO 8307:2018. The standard specifies a reproducible test method (ball rebound) to determine the resilience of flexible cellular polymeric materials (foams). It replaces EN ISO 8307:2007 and is intended for use in quality control, product development and comparative testing of flexible foams.
Key topics and technical requirements
- Test principle: A steel ball is dropped vertically onto a conditioned foam test piece from a fixed height; the rebound height is measured and expressed as resilience.
- Apparatus:
- Transparent vertical tube (inside diameter 30–65 mm) mounted truly vertical on a rigid baseplate.
- Steel ball: diameter 16.0 mm ± 0.5 mm, mass 16.8 g ± 1.5 g.
- Drop height: 500 mm ± 0.5 mm; release mechanism to avoid rotation and off-centre impacts.
- Manual-reading tube: graduated in percent with full circles every 5% to reduce parallax.
- Automatic systems allowed if demonstrated equivalent; electronic measurement must meet ±1% of total drop height (±5 mm).
- Test pieces:
- Plane, parallel faces; minimum thickness 50 mm and area at least 100 × 100 mm. Thinner samples may be plied (without cement) to reach 50 mm.
- For moulded products, top skin removed.
- Number and conditioning:
- Three test pieces per sample.
- Condition at least 16 hours in specified atmospheres (23 °C ±2 °C / 50% RH ±5% or 27 °C ±2 °C / 65% RH ±5%). Testing normally not less than 72 h after manufacture unless stability demonstrated earlier.
- Preflexing:
- Required for open‑cell foams: compress twice to 75–80% thickness at 0.4–6 mm/s, then recover 10 min ±5 min.
- Reference: Normative reference to ISO 23529 for preparation and conditioning procedures.
Applications and users
This standard is used by:
- Foam and flexible cellular polymer manufacturers for product specification and quality control.
- Materials testing laboratories and R&D teams comparing resilience across formulations or processing variants.
- Certification bodies and purchasers requiring standardized resilience data for seating, bedding, insulation or cushioning applications.
Practical uses include ranking comfort/performance, verifying batch consistency, and assessing material suitability for end-use requirements.
Related standards (if applicable)
Keywords: EN ISO 8307:2018, ISO 8307, ball rebound method, foam resilience test, flexible cellular polymeric materials, resilience by ball rebound, test apparatus, conditioning.
