Overview
EN ISO 3262-19:2021 / ISO 3262-19:2021 - "Extenders - Specifications and methods of test - Part 19: Precipitated silica" is the CEN-endorsed international standard that specifies requirements and corresponding test methods for precipitated silica as an extender/filler. Published in 2021 and endorsed by CEN, this second edition supersedes the 2000 version and aligns with the ISO 3262 series for pigments and extenders.
Key topics and requirements
The standard defines the scope, sampling and detailed laboratory test procedures that manufacturers and testing laboratories use to verify precipitated silica quality. Major technical topics covered include:
- Specification scope - Essential and conditional requirements for precipitated silica used as an extender/filler.
- Sampling - Guidance consistent with ISO 15528 for representative sampling of consignments.
- Analytical methods - Detailed procedures and apparatus for:
- Determination of silica content
- Determination of carbon content
- Determination of residue on sieve (fines/coarse fraction)
- General tests referenced from the ISO 787 series (e.g., volatile matter at 105 °C, oil absorption value, pH, tamped volume)
- Test reporting - Required information to include in laboratory reports to demonstrate compliance.
- Precision and reproducibility - Statements on repeatability and reproducibility for key determinations are included.
- Normative references - Cross-references to related standards such as ISO 3696 (lab water), ISO 5794‑1 (silica for rubber), and other parts of ISO 3262.
The document contains reagent and apparatus lists, procedural steps, and expression of results - ensuring harmonized quality control and comparability across laboratories.
Applications and users
EN ISO 3262-19:2021 is intended for anyone involved in the manufacture, testing, specification or procurement of precipitated silica:
- Manufacturers and suppliers - to specify product quality and create product data sheets.
- Quality control laboratories - for routine testing and release of silica-based extenders.
- Formulators in coatings, paints, adhesives, sealants, and rubber - to select appropriate precipitated silica grades based on particle size, silica content and surface characteristics.
- Procurement and compliance teams - to define acceptance criteria in supply contracts and conformity assessments.
- Standards bodies and test houses - for harmonized methodology when comparing materials across markets.
Related standards
- ISO 3262 (series) - Parts covering extenders and general test methods
- ISO 787 series - General methods of test for pigments and extenders
- ISO 5794-1 - Silica, precipitated, hydrated (non-rubber tests)
- ISO 15528 - Sampling for paints, varnishes and raw materials
Using EN ISO 3262-19:2021 ensures consistent, reproducible testing and clear specification of precipitated silica properties for industrial applications such as paints, coatings, rubber compounding and general filler use.