ISO 19595:2017

Overview

ISO 19595:2017 - Natural aggregates for concrete defines the properties and requirements for natural aggregates (processed by crushing, washing, sieving) used in concrete. It applies to aggregates with an oven-dried particle density greater than 2.00 Mg/m³ (2 000 kg/m³) (see ISO 22965). The standard includes a general environmental requirement that aggregates must not release harmful substances above permitted national limits, and it allows national or project specifications to add or deviate from requirements.

Key topics and technical requirements

ISO 19595:2017 structures technical requirements around measurable properties and testing. Major areas covered:

• Geometrical requirements

  • Aggregate size designations and grading (coarse, fine, all-in)
  • Fines content and fines quality
  • Particle shape (flakiness index, shape index) and shell content

• Physical requirements

  • Resistance to fragmentation, wear and polishing
  • Particle density and water absorption
  • Bulk density and abrasion resistance (including for surface courses)
  • Specific tests referenced (e.g., Los Angeles, Micro‑Deval)

• Chemical requirements

  • Petrographic description and constituents that affect concrete performance
  • Sulfur compounds (acid‑soluble sulfate and total sulfur)
  • Chlorides and materials that alter setting/hardening

• Durability

  • Soundness, freeze–thaw resistance (including salt exposure), drying shrinkage
  • Alkali–silica reactivity screening and evaluation

• Conformity, designation and labelling

  • Evaluation of conformity, recommended designation formats and marking requirements for traceability

• Normative test references

  • The document refers to specific test methods such as ISO 6274, ISO 6782, ISO 6783 and ISO 7033.

Practical applications and who uses this standard

ISO 19595:2017 is essential for organizations involved in concrete materials and quality control:

• Aggregate producers - to certify products meet international requirements for concrete use.
• Concrete manufacturers and ready‑mix plants - for aggregate selection and quality assurance.
• Civil and structural engineers, specifiers and contractors - to specify appropriate aggregates for structural, precast or pavement concrete.
• Testing laboratories - to carry out and report required geometrical, physical and chemical tests.
• Regulators and procurement teams - to ensure materials meet environmental and safety thresholds.

Practical applications include selection and acceptance criteria for aggregates in structural concrete, road surface courses, precast elements, and durability‑sensitive projects where freeze–thaw, abrasion or alkali‑silica reactivity are concerns.

Related standards

• ISO 22965 (all parts) - requirements for end use of aggregates in concrete (referenced for particle density and use conditions)
• Test method standards: ISO 6274, ISO 6782, ISO 6783, ISO 7033

ISO 19595:2017 supports consistent specification, testing and supply of natural aggregates, helping ensure durable, safe and compliant concrete construction.