Overview
EN ISO 534:2011 - "Paper and board - Determination of thickness, density and specific volume" (CEN adopted) defines standardized methods for measuring the dimensional and volumetric properties of paper and board. The standard specifies two measurement approaches (single sheet thickness and bulking thickness), the required apparatus and calibration, sampling and conditioning, and the calculations to derive apparent density and apparent specific volume from thickness and grammage data. It is not applicable to corrugated fibreboard or tissue products (use ISO 12625-3 for tissue).
Key topics and technical requirements
- Two measurement methods
- Single sheet thickness: direct measurement of one sheet under a specified static load.
- Bulking thickness: measurement of a pack of sheets (typically ten) to determine bulk properties of paper.
- Apparatus
- Use a dead-weight micrometer with two plane, parallel circular faces; pressure during measurement: (100 ± 10) kPa.
- One pressure face specified as (16.0 ± 0.5) mm diameter; micrometer must meet performance requirements (e.g., indication error: ±2.5 µm or ±0.5%, repeatability: 1.2 µm or 0.5%, parallelism error: 5 µm or 1%).
- Thickness gauges approximating 10%, 30%, 50%, 70%, 90% of full scale for calibration.
- Sampling and preparation
- Condition samples per ISO 187 and sample per ISO 186.
- Single-sheet test pieces: minimum 60 × 60 mm, up to 100 × 100 mm for board; prepare at least 20 test pieces.
- Bulking test pieces: sheets preferably 200 × 250 mm (machine direction noted), packs normally of 10 sheets, prepare at least 4 test pieces.
- Calculations
- Procedures to compute apparent sheet density, apparent bulk density, apparent specific sheet volume, and apparent specific bulk volume from measured thickness and grammage (referenced ISO 536 for grammage).
- Calibration & precision
- Annexes include micrometer verification/calibration and precision data for method reproducibility.
Applications and users
EN ISO 534:2011 is used by:
- Paper and board manufacturers for quality control and product specification.
- Packaging designers and converters assessing board or paper bulk and density for performance and cost.
- Printing houses and papermaking labs evaluating sheet thickness consistency and printability.
- Procurement, specification writers and testing laboratories for compliance, acceptance testing and R&D.
Practical benefits include reliable comparison of materials, consistent procurement specs, and inputs to converting and printing process control.
Related standards
- ISO 187 - conditioning and testing atmosphere
- ISO 186 - sampling for average quality
- ISO 536 - determination of grammage
- ISO 12625-3 - tissue paper thickness methods (for tissue products)
- ISO 4046-3 - definitions related to “board”
Keywords: EN ISO 534:2011, ISO 534:2011, paper thickness, bulking thickness, apparent density, specific volume, dead-weight micrometer, paper testing, standards for paper and board.
