ISO 17892-4:2016

Overview

ISO 17892-4:2016 - Geotechnical investigation and testing - Laboratory testing of soil - Part 4: Determination of particle size distribution - specifies accepted laboratory procedures to determine the particle size distribution (PSD) of soils. It covers methods by sieving, sedimentation (hydrometer and pipette methods), or a combination of both for non‑cemented soils with particle sizes less than 125 mm. The standard underpins soil classification and many geotechnical and geohydrological property assessments used in site investigation and design. ISO 17892-4:2016 also fulfils particle size testing requirements in accordance with EN 1997-2.

Key topics and technical requirements

• Scope and applicability: Laboratory determination of PSD by sieving and/or sedimentation for geotechnical investigations; excludes advanced instrumental counting (laser, x‑ray) and cemented soils.
• Test methods:
  • Sieving for coarse fractions (recommended sieves: 63, 20, 6.3, 2.0, 0.63, 0.20, 0.063 mm).
  • Hydrometer method for fine fractions: specifies hydrometer characteristics (range ~0.9950–1.0300 g/ml, graduations ~0.0005 g/ml), sedimentation cylinders, temperature control and mixing.
  • Pipette method for fine sedimentation sampling: pipette volume calibration, sampling containers and handling.
• Equipment and accuracy: Balance accuracy (0.01 g or 0.1% for sieving/hydrometer; 0.001 g for pipette), ovens, timing, thermometers, test sieves per ISO 3310, sedimentation cylinders and mechanical mixers/shakers.
• Pre‑treatment and corrections: Guidance on chemical pre‑treatment (carbonate, salts, organics) and sample separation to avoid altering PSD.
• Quality checks and reporting: Calibration, maintenance (Annex A), required test data (masses retained, % passing, hydrometer readings, computed equivalent diameters) and presentation of PSD curve.

Applications and users

ISO 17892-4:2016 is used by:

• Geotechnical and geohydrological engineers for soil classification, foundation and slope design, permeability and settlement assessments.
• Construction and site investigation laboratories performing standardized PSD testing.
• Consulting firms, contractors and regulators requiring reproducible laboratory PSD data for design verification and compliance.

Practical benefits include consistent PSD curves for soil classification, improved comparability between labs, and methods aligned with EN 1997 design codes.

Related standards

• EN ISO 14688-1 (soil identification/classification)
• ISO 3310 series (test sieves)
• ISO 386 (thermometers)
• EN/ISO 17892 series (other laboratory soil tests)
• EN 1997-1 / EN 1997-2 (geotechnical design standards)

Keywords: ISO 17892-4:2016, particle size distribution, PSD, geotechnical investigation, sieving, hydrometer method, pipette method, laboratory testing of soil, soil classification.