Overview
ISO 10136-1:1993 sets out the international standard procedure for the determination of silicon dioxide (SiO₂) in extract solutions from glass and glassware using molecular absorption spectrometry. Developed by ISO Technical Committee 48/SC 5, this standard provides a reliable, sensitive method for analyzing silica levels - a critical factor in the chemical durability and safety of glass products across industries. The standard applies to all types of glassware, including laboratory, pharmaceutical, food and drink packaging, as well as tableware and kitchenware.
Key Topics
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Scope and Applicability
- Suited for extract solutions obtained from any glass or glassware type, particularly useful in laboratory, pharmaceutical, and food contact materials.
- Applicable to both finished products (glass articles) and raw glass materials.
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Analytical Principle
- Determination based on forming a blue silicomolybdate complex via reaction with ammonium molybdate and a reducing solution.
- Measurement involves a molecular absorption spectrophotometer set at 800 nm with 10 mm optical cells.
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Technique Highlights
- Sensitive detection of low silica concentrations, suitable for stringent quality assurance.
- Standardizes measurement methodology, ensuring reproducibility and comparability across laboratories.
Applications
ISO 10136-1:1993 is essential for sectors where glass quality and durability are paramount. Its main applications include:
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Laboratory Glassware Analysis
Ensuring chemical resistance and low extractable silica for lab applications, crucial for accurate analytical results and contamination prevention.
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Pharmaceutical Packaging Testing
Verifying glass neutrality and safety for medicines, preventing contamination by silica leaching and assuring compliance with regulatory requirements.
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Food and Beverage Packaging
Assessing the chemical durability of containers to maintain food safety and product quality over time.
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Kitchenware and Tableware Assessment
Evaluating resistance to acidic or basic contents, supporting consumer safety and product lifespan.
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R&D and Quality Control
Comparing new glass formulations or batches for silica release, aiding in product development and batch release testing.
Related Standards
For comprehensive quality and safety evaluations, refer to these related international standards:
- ISO 10136-2: Analysis of sodium oxide and potassium oxide in extract solutions (flame spectrometry)
- ISO 10136-3: Determination of calcium oxide and magnesium oxide (flame atomic absorption spectrometry)
- ISO 10136-4: Determination of aluminium oxide by molecular absorption spectrometry
- ISO 10136-5: Determination of iron(III) oxide by molecular absorption and flame atomic absorption spectrometry
- ISO 10136-6: Determination of boron(III) oxide by molecular absorption spectrometry
- ISO 4802: Hydrolytic resistance testing of glass containers
- ISO 719 and ISO 720: Hydrolytic resistance of glass grains
Summary
By following ISO 10136-1:1993, organizations can ensure consistent, accurate determination of silicon dioxide in glass extract solutions-contributing to product safety, regulatory compliance, and improved quality assurance in glassware manufacturing and usage. This standardized spectrometric method is a valuable tool across laboratory, pharmaceutical, food, and consumer product industries.
Open preview (PDF)Glass and glassware — Analysis of extract solutions — Part 1: Determination of silicon dioxide by molecular absorption spectrometry