Overview
EN ISO 10195:2021 - Leather - Chemical determination of chromium(VI) content in leather - Thermal pre‑ageing of leather and determination of hexavalent chromium - is a CEN-adopted ISO method that defines a thermal pre-ageing procedure to indicate the tendency of chromium(III)-tanned leather to form hexavalent chromium (Cr(VI)). The standard is a predictive laboratory test (not a simulation of real use or production conditions) and is intended to be followed by chemical determination of Cr(VI) using ISO 17075‑1 (colorimetric) or ISO 17075‑2 (chromatographic).
Key topics and technical requirements
- Scope: Applies to all types of chromium-tanned leather to assess potential Cr(VI) formation after controlled thermal ageing.
- Pre-ageing conditions:
- Two temperature options: 60 ± 2 °C (general purpose) or 80 ± 2 °C (for leather exposed to critical conditions).
- Ageing duration: (24 ± 1) h in a closed vessel.
- Relative humidity (natural convection, oven closed): physically lower than 20% at 60 °C and lower than 10% at 80 °C.
- Specimen preparation & mass:
- Sampling per ISO 2418 (or described sampling if not possible).
- Specimen prepared per ISO 4044 and cut to 3–5 mm pieces.
- Test mass: (2.0 ± 0.1) g.
- Apparatus essentials:
- Static oven (no fan/air circulation) with ±2 °C control and inert interior.
- 250 ml Erlenmeyer flask (used during heating and to start ISO 17075 extraction).
- Temperature/humidity measurement and an analytical balance with 0.1 mg accuracy.
- Analysis: After cooling (2 h ± 15 min), determine Cr(VI) according to ISO 17075‑1 or ISO 17075‑2; calculate and report Cr(VI) content per those methods.
- Test report must include: reference to ISO 10195, leather description/sampling, chosen pre‑ageing method, Cr(VI) amount, and the analytical method used.
Applications and who uses it
- Useful for tanneries, leather chemical laboratories and quality control teams assessing risks of Cr(VI) formation in chromium‑tanned leather.
- Employed by product compliance officers, footwear and upholstery manufacturers, automotive interior suppliers, garment and glove makers, and testing laboratories to support safety declarations and supplier specifications.
- Relevant for authorities and certification bodies that require laboratory evidence of Cr(VI) behavior in leather components.
Related standards
EN ISO 10195:2021 provides a reproducible laboratory pre-ageing protocol to help stakeholders evaluate hexavalent chromium risk in chromium‑tanned leather and to ensure consistent Cr(VI) testing workflows.