Glass and Ceramics Standards Summary – September 2025

Looking back at September 2025, the Glass and Ceramics Industries sector experienced targeted standardization activity, with a notable focus on the durability and reliability of raw optical glass. During the month, a key international standard—ISO 9689:2025—was published, reflecting a broader trend towards enhanced material performance and rigorous testing in specialty glass applications. For industry professionals, quality managers, compliance officers, and technical specialists, this retrospective overview presents essential insights into this standard, why it matters, and what it means for ongoing compliance efforts and quality assurance.

The value of this monthly summary lies not just in catching up on what was published, but in analyzing how these developments signal industry priorities, advancements in testing methodology, and ongoing commitments to safety and performance. With one significant standard covered this month, the following analysis provides clarity for those seeking to remain informed and proactive within the ceramics and glass field.

Monthly Overview: September 2025

September 2025 saw the release of a single, but highly pertinent, standard for the Glass and Ceramics Industries. The publication of ISO 9689:2025 signals a deepening industry focus on the resilience of optical materials, in line with global demands for higher precision, longevity, and chemical resistance in optical componentry.

This standard emerged in a context where optical glass suppliers and manufacturers are facing increasing scrutiny regarding product consistency and environmental resistance, particularly as applications in photonics, imaging, and high-performance optics continue to grow. The updated requirements within the 2025 edition respond to both longstanding challenges—such as mitigating chemical degradation during cleaning—and emerging needs prompted by advances in industrial washing processes and stringent environmental controls.

Comparing September 2025's standardization activity to previous periods, where broader material and process standards were common, this month's focus underscores an evolution towards more specialized, test-driven, and application-specific requirements. This publication suggests the industry is doubling down on end-use reliability, customer trust, and international harmonization.

Standards Published This Month

ISO 9689:2025 – Raw Optical Glass: Resistance to Attack by Phosphate Detergents Testing and Classification

Raw optical glass – Resistance to attack by aqueous alkaline phosphate-containing detergent solutions at 50 °C – Testing and classification

Scope and Purpose: ISO 9689:2025 describes a precise laboratory test method for evaluating the resistance of raw optical glass to attack by aqueous alkaline phosphate-containing detergent solutions at 50 °C. The standard further prescribes a classification system for optical glasses based on their demonstrated resistance (termed phosphate resistance) under these conditions. The primary purpose is to ensure that glass materials used in optical applications can withstand aggressive cleaning and maintenance regimes without significant degradation or loss of functionality.

Key Requirements and Specifications: The standard details the following core requirements:

• Preparation, polishing, and cleaning procedures to obtain accurate, repeatable results
• Exposure of glass samples to a rigorously formulated alkaline phosphate detergent solution at a controlled temperature (50 °C)
• Measurement of material loss as a function of time, calculating the duration required to remove a 0.1 µm surface layer
• Categorization of glasses into phosphate resistance classes (PR) according to these measured results
• Stringent requirements for reagents, apparatus—especially the use of corrosion-resistant test vessels and precise thermostatic controls—and analytical measurement techniques

Who Needs to Comply: This standard is directly applicable to:

• Optical glass manufacturers and their suppliers
• Laboratories conducting raw materials testing and quality assurance
• Optical component producers requiring third-party verified material properties
• Quality managers responsible for documentation and certification
• Procurement specialists evaluating and specifying materials for high-reliability applications

Broader Regulatory Context: ISO 9689:2025 both aligns with and complements foundational standards such as ISO 3585 (Borosilicate glass 3.3 — Properties) and surface texture requirements found in ISO 10110-8. By stipulating rigorous test and classification protocols, it fills a crucial gap for users needing assurance of stable glass performance under repeated exposure to alkaline phosphate-based solutions—which are prevalent in modern cleaning and sterilization procedures.

Notable Features and Changes: This second edition introduces several technical updates over the previous (1990) version, including:

• Updated polishing and lapping methods for improved reproducibility
• Addition of Annex A covering enhanced guidance for glass processing
• Refined procedures for preparing and purifying phosphate test solutions
• More precise definitions of test apparatus and environmental controls
• Recalibrated classification criteria reflecting contemporary glass compositions

Key highlights:

• Sets forth a reference test method for phosphate detergent resistance of optical glass at 50 °C
• Mandates classification of glass into resistance categories, aiding in material selection and specification
• Provides clarified, updated guidance on sample preparation, solution chemistry, and apparatus

Access the full standard:View ISO 9689:2025 on iTeh Standards

Common Themes and Industry Trends

While September 2025 saw a single standardization event, the themes visible here are widely relevant. Several industry trends are reinforced by the release of ISO 9689:2025:

• Rising stringency in quality control: The move towards test-driven classification of glass reflects heightened customer demands for traceable, repeatable performance, especially in sectors like photonics, precision optics, and specialty imaging.
• Durability and end-use reliability: The ability of glass to withstand aggressive cleaning without deterioration is critical in environments ranging from healthcare and analytical laboratories to defense and aerospace.
• Harmonization and interoperability: The alignment of procedures and definitions across related standards makes it easier for global supply chains to ensure compatibility, reduce disputes, and accelerate certification processes.

The focus on a single, highly targeted standard points towards further regulatory specialization—where precise material behaviors, rather than generic properties, are prioritized as differentiators in global markets.

Compliance and Implementation Considerations

For organizations impacted by ISO 9689:2025, practical steps for compliance—and timelines for implementation—should be carefully planned. Consider these recommendations:

1. Gap analysis: Identify existing processes and specifications that may require revision in light of new polishing, lapping, and sample preparation protocols or tighter requirements for solution preparation and testing apparatus.
2. Training and laboratory validation: Ensure laboratory technicians and quality staff understand updated procedures, terminologies, and classification methods. Validate equipment for temperature control, reagent purity, and analytical balances.
3. Documentation and traceability: Update technical files, supplier specifications, and purchasing documentation to reference the latest standard edition. Ensure laboratory reports and certificates acknowledge compliance with ISO 9689:2025.
4. Material selection and sourcing: Work proactively with suppliers to source certified optical glass meeting the updated resistance classifications.

Timeline Considerations: While immediate compliance may not be mandated, regulatory or supply chain requirements may require adoption within 6 to 12 months following publication. Early adoption provides competitive and risk reduction advantages.

Resources for Getting Started:

• Secure access to the full standard via iTeh Standards
• Review cross-referenced standards (ISO 3585, ISO 10110-8) for upstream and downstream alignment
• Consult with industry associations, certification bodies, and technical experts for interpretation support

Conclusion: Key Takeaways from September 2025

September 2025’s sole standardization event for the Glass and Ceramics Industries—ISO 9689:2025—offered targeted, yet impactful, guidance for all professionals concerned with optical glass durability and reliability. By updating and refining laboratory testing and material classification protocols, the standard reinforces industry-wide priorities around end-use resilience and supply chain transparency.

In summary, those involved in procurement, specification, research and development, and laboratory quality will benefit from:

• Understanding updated resistance classification for raw optical glass
• Immediate guidance for aligning testing, documentation, and purchasing protocols
• Long-term value in standardized approaches to durability verification

Staying up to date with rigorous standards such as ISO 9689:2025 is essential for ensuring product quality, safety, and competitiveness in the international glass and ceramics market.

Access the standard in full:View ISO 9689:2025 on iTeh Standards

For a comprehensive resource on Glass and Ceramics Industries standards and ongoing updates, visit iTeh Standards.