Overview
ISO 4802-1:2023 - Glassware - Hydrolytic resistance of the interior surfaces of glass containers - Part 1: Determination by titration method and classification defines a standardized laboratory test and classification scheme for the hydrolytic resistance of interior glass surfaces. The method exposes filled containers to water at (121 ± 1) °C for (60 ± 1) min, measures released alkaline species in the extraction solution by titration with hydrochloric acid, and classifies containers (HC 1, HC 2, HC 3, HC B, HC D) according to the measured response. The procedure is intended for as-produced containers and aligns key aspects with the European Pharmacopoeia for improved reproducibility.
Key technical topics and requirements
- Test principle: Surface test where containers are filled with specified water, loosely capped, autoclaved under defined conditions, then analyzed by titration of an aliquot of the extraction solution. Hydrolytic resistance is inversely proportional to the acid volume required.
- Autoclaving conditions: Precisely defined cycle at 121 °C for 60 minutes to simulate hydrolytic attack (document specifies detailed cycle to increase interlaboratory reproducibility).
- Sample preparation: Requirements for sample size, determination of filling volume (procedures for different container geometries such as ampoules, syringes, round- or flat‑bottomed containers), and cleaning prior to testing.
- Analytical method: Titration reagents and apparatus, aliquoting, and calculation of released alkali-reacting ions; expression of results and reporting.
- Classification and designation: Defined container classes (HC 1, HC 2, HC 3, HC B, HC D) and guidance on distinguishing classes (notably HC 1 vs HC 2), including applicability to parenteral and non-parenteral preparations.
- Quality aspects: Requirements for test reporting, reproducibility data, and a formal classification table for container-specific limits.
Practical applications - who uses this standard
- Pharmaceutical glass-container manufacturers (bottles, vials, ampoules, syringes, cartridges) for product development and quality control.
- Medical device and packaging engineers specifying primary packaging for parenteral and non-parenteral formulations.
- Quality control and analytical laboratories performing hydrolytic-resistance testing and batch release.
- Regulatory and compliance teams relying on objective classification (HC classes) to demonstrate suitability of glassware for specific pharmaceutical applications.
- Procurement and materials specialists selecting glass types (e.g., borosilicate, soda-lime-silica) and surface treatments.
Related standards
ISO 4802-1:2023 is a practical, reproducible reference for assessing hydrolytic durability of glass containers and ensuring suitable packaging performance for pharmaceutical and medical applications.