ISO 12625-9:2015

Overview

ISO 12625-9:2015 describes a standardized laboratory method to determine the ball burst strength (resistance to mechanical penetration) of tissue paper and tissue products. The test measures the maximum force required for a polished stainless-steel ball to penetrate a clamped tissue specimen. The standard uses a 50 mm clamping device (internal diameter (50.0 ± 0.2) mm) to ensure compatibility with common sample sizes and consistency with ISO 12625-11 (wet ball burst).

Keywords: ISO 12625-9, ball burst strength, tissue paper testing, burst index, tissue product quality

Key Topics and Technical Requirements

• Scope and applicability: Applies to tissue papers and tissue products (single- or multi-ply as supplied); not intended for other paper types unless agreed.
• Clamping system: Two concentric rings with rubber-covered clamping surfaces (1.0–2.0 mm thick, 70–85 IRHD), inner diameter 50.0 ± 0.2 mm. Clamping pressure must prevent slippage without damaging the specimen.
• Penetration (burst) ball: Highly polished stainless-steel sphere, diameter (16 ± 0.2) mm, sphericity better than 1 µm; rod diameter smaller than the ball and centered on the clamps.
• Drive and speed: Static uniaxial testing machine moving at (125 ± 5) mm/min perpendicular to specimen plane.
• Force measurement: Load cell accuracy ±1% of reading or ±0.1 N (whichever greater); measuring range 0.1 N to 50 N; calibration per ISO 7500-1.
• Sampling and conditioning: Sampling per ISO 186; condition specimens in standard atmosphere per ISO 187 and maintain atmosphere during testing.
• Procedure and data: Test at least 10 conditioned specimens, record maximum bursting force (F) to three significant figures. Calculate mean F, standard deviation and burst index X = F_mean / grammage (g, from ISO 12625-6).
• Reporting: Include reference to ISO 12625-9, test date/place, conditioning, sample ID, mean bursting force, standard deviation, min/max values and methodology.

Applications and Users

• Quality control: Manufacturers of toilet tissue, facial tissues, paper towels and converted tissue products use this test to monitor mechanical strength and product consistency.
• Product development: R&D teams evaluate the effect of fiber mix, processing, creping and lamination on resistance to puncture.
• Supplier/customer agreements: Provides an objective method for contractual testing and specification compliance.
• Regulatory and certification labs: Independent testing labs and certification bodies use ISO 12625-9 for benchmark comparisons and performance claims.

Keywords: tissue strength test, puncture resistance, burst index calculation, tissue product QC

Related Standards

• ISO 12625-1 (terms), ISO 12625-6 (grammage), ISO 12625-11 (wet ball burst)
• ISO 186 (sampling), ISO 187 (conditioning), ISO 7500-1 (force-measuring calibration)
• ISO 287 and ISO 638 (moisture determination referenced in guidance)

This standard delivers a repeatable, calibrated method to quantify tissue resistance to penetration-critical for product performance assessment, specification setting, and manufacturing control.