Overview
ISO 11093-2:2025 - Paper and board - Testing of cores - Part 2: Conditioning of test samples specifies the conditioning atmospheres and practical steps for preparing paper and board cores prior to testing. Aligned with ISO 187, this standard defines the temperature and relative humidity regimes, apparatus requirements and the conditioning procedure needed to establish a stable moisture equilibrium in test pieces. It replaces the earlier 1994 edition and updates terminology (e.g., “conditioning rooms” in place of “climatic chambers”).
Key topics and requirements
- Conditioning atmospheres (Table 1):
- 23/50: 23 ± 1 °C and 50 ± 2 % RH - preferred (default unless agreed otherwise)
- 27/65: 27 ± 1 °C and 65 ± 2 % RH - for tropical countries
- Apparatus: conditioning room with automatic control of temperature and relative humidity, and air circulation ensuring uniform conditions; atmospheric verification in accordance with ISO 187:2022 (Annex A).
- Pre-drying: predry test pieces for 48 h at 40 °C ± 2 °C and 20–35 % RH to ensure adsorption-based moisture adjustment before conditioning.
- Conditioning procedure:
- Position samples for free air access (no stacking; avoid overcrowding).
- Consider moisture equilibrium reached when two consecutive weighings (minimum 48 h apart) differ by ≤ 0.1 % of mass.
- Ensure pre-conditioning air moisture content is lower than the conditioning atmosphere.
- Conditioning report: include reference to ISO 11093-2:2025, specimen type, place/date, number of specimens, conditioning atmosphere and duration, and any deviations or relevant circumstances.
Applications and users
ISO 11093-2:2025 is intended for laboratories, manufacturers and quality assurance teams involved with:
- Paper and board core manufacturing and testing
- Converter or rewind operations using paper cores for reels and rolls
- Independent testing laboratories performing mechanical or dimensional tests where moisture state affects results
- R&D and process engineering groups validating material performance under standard atmospheres
Using ISO 11093-2 ensures reproducible, comparable test conditions and reliable test data for contract testing, quality control, acceptance testing and regulatory compliance.
Related standards
- ISO 187:2022 - Standard atmosphere for conditioning and testing; procedure for monitoring atmosphere and conditioning of samples (normative reference)
- ISO 554:1976 - Standard atmospheres for conditioning and/or testing - specifications (referenced for tolerance values)
- Other parts of the ISO 11093 series for additional core testing methods
Keywords: ISO 11093-2:2025, conditioning of test samples, conditioning atmosphere, paper and board cores, ISO 187, pre-drying, moisture equilibrium, conditioning room.
