EN ISO 3262-7:2023 PDF

Overview

EN ISO 3262-7:2023 (adopted by CEN as EN ISO 3262-7:2023) specifies requirements and corresponding methods of test for dolomite used as an extender. This second edition replaces the 1998 version and aligns dolomite specification and testing with the ISO 3262 series for pigments and extenders.

Key purpose:

• Provide clear composition limits and quality metrics for dolomite grades
• Reference harmonized test methods for consistent results across laboratories
• Define sampling and reporting requirements to support quality control

Key Topics

The standard covers essential and conditional requirements and refers to established test methods from the ISO 787 series and others. Important elements include:

• Definition: Dolomite is defined as natural calcium magnesium carbonate (CaMg(CO3)2).
• Grades and composition: Minimum CaMg(CO3)2 content for specified grades:
  • Grade A: ≥ 97 % (mass fraction)
  • Grade B: ≥ 90 %
  • Grade C: ≥ 80 %
• Fixed test properties (selected examples from the standard):
  • Matter volatile at 105 °C (ISO 787-2) - maximum 0.3 %
  • Loss on ignition (ISO 3262-1) - 46 to 48 %
  • Matter soluble in water (hot extraction) (ISO 787-3) - maximum 0.2 %
  • pH of aqueous suspension (ISO 787-9) - range 8 to 10.5
  • Matter insoluble in hydrochloric acid - limits to be agreed between parties for specific products
• Conditional requirements (to be agreed or tested as required):
  • Residue on 45 µm sieve (ISO 787-7)
  • Particle size distribution by laser diffraction (ISO 8130-13)
  • Colour, lightness, resistivity of aqueous extract (ISO 787-14)

Applications

EN ISO 3262-7:2023 is primarily intended to support quality control and specification of dolomite extenders in industrial formulations, including:

• Coatings and paints
• Pigment and extender blends
• Raw materials quality assurance for manufacturers and suppliers

Practical benefits:

• Harmonised acceptance criteria reduce disputes between suppliers and purchasers
• Clear test-method references enable reproducible laboratory results
• Defined sampling (ISO 15528) and test-report content improve traceability and conformity assessment

Related Standards

The document explicitly references and relies on other ISO standards for methods and terminology, including:

• ISO 3262-1 - Extenders: Introduction and general test methods
• ISO 787 series (Parts 2, 3, 7, 9, 14) - General methods of test for pigments and extenders
• ISO 8130-13 - Particle size analysis by laser diffraction
• ISO 15528 - Sampling for paints, varnishes and raw materials
• ISO 18451-1 - Terminology for pigments, dyestuffs and extenders

Notes on Use

• Sampling shall follow ISO 15528 to obtain a representative sample.
• Test reports must reference ISO 3262-7:2023 and include identification, methods used, results, deviations, anomalies and test date.

For procurement, laboratory implementation and product specification, EN ISO 3262-7:2023 provides a concise, harmonised framework to assess dolomite extender quality and ensure consistent performance in manufacturing and formulation contexts.