Overview
EN ISO 7965-2:1996 - Sacks - Drop test - Part 2: Sacks made from thermoplastic flexible film (ISO 7965-2:1993) specifies a standardized method for vertical impact testing (sacks drop test) of filled sacks made from thermoplastic flexible film. The standard defines the drop-test principle - raising a filled sack and releasing it to strike a rigid surface after free fall - and details test procedures, reporting and acceptance criteria. It can be used as a single-impact investigation or as part of a sequence simulating distribution systems that include vertical impact hazards.
Key topics and technical requirements
- Scope and principle: Vertical impact testing of filled thermoplastic-film sacks by free-fall drop onto a rigid surface.
- Apparatus requirements:
- Lifting arrangement that does not damage the sack.
- Means to hold the sack prior to release and a release mechanism that does not obstruct the fall.
- Impact surface: one-piece, mass at least 50× the heaviest test sack, flat (surface variation ≤ 2 mm), rigid (≤ 0.1 mm deformation under 10 kg/100 mm²), and large enough to ensure the entire sack falls on it.
- Sampling and conditioning: Sampling per ISO 7023 and conditioning of filled, closed sacks per ISO 2233 (designated atmospheres).
- Drop modes: Flat (face/back), side (left/right), and butt (bottom) drops with defined starting heights and increments:
- Flat/side progressive start: 0.85 m, increment 0.15 m.
- Butt progressive start: 0.30 m, increment 0.05 m.
- Test methods:
- Progressive drop-height method (incrementing height until breakage).
- Constant drop-height method (selected height producing ~10 drops to rupture).
- Limit-height method (calculate lowest height causing first-drop failure).
- Failure definition: A sack is considered broken when spillage of contents occurs; slight discharge (e.g., through closures) is not necessarily a failure if no further leakage follows.
- Reporting: Full details of sack construction, filling mass, drop heights, number of drops to breakage, method of holding, location/type of failures, and other test parameters. Annex C provides a report format.
Applications and users
- Practical uses: qualification and quality control of flexible-film sacks for agricultural, chemical, mineral, food and industrial commodities subjected to handling and transport impacts.
- Who uses it: packaging engineers, quality assurance teams, manufacturers of thermoplastic film sacks, testing laboratories, shippers and logistics professionals assessing packaging performance under vertical impact hazards.
Related standards
- ISO 7965-1 / EN ISO 7965-1 - Drop test for paper sacks (companion Part 1)
- ISO 2248 - General vertical impact test principles referenced
- ISO 2233 - Conditioning of filled transport packages
- ISO 7023 - Sampling of empty sacks
Keywords: EN ISO 7965-2:1996, sacks drop test, thermoplastic flexible film, vertical impact testing, drop height, butt drop, packaging test methods, sack performance.
