Overview
ISO 18227:2014 - Soil quality: Determination of elemental composition by X‑ray fluorescence (XRF) defines a standardized procedure for quantitative analysis of major and trace elements in homogeneous solid waste, soil, and soil‑like materials using EDXRF (energy dispersive) or WDXRF (wavelength dispersive) spectrometry. The method relies on calibrations with matrix‑matched standards and covers a wide suite of elements (Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Y, Zr, Nb, Mo, Ag, Cd, Sn, Sb, Te, I, Cs, Ba, Ta, W, Hg, Tl, Pb, Bi, Th, U). Quantifiable concentrations range from approximately 0.0001% up to 100%, depending on element and instrument.
Key topics and requirements
- Scope and applicability: quantitative analysis for homogeneous solids; Annex A provides a semi‑quantitative screening method for wastes, sludges and soils.
- Instrumentation: requirements for EDXRF and WDXRF systems, detectors, source modifiers and operating conditions.
- Sample preparation: drying and dry‑mass determination, milling, preparation of pressed pellets, preparation of fused beads, and options for powder or liquid cups.
- Calibration: mandatory use of matrix‑matched standards for quantitative results; manufacturer matrix‑independent calibrations acceptable for screening (Annex A).
- Quality control: procedures for drift correction, blank tests, and use of certified reference materials (CRMs) and quality control samples.
- Interferences and error sources: inter‑element effects, absorption/augmentation, matrix effects and instrument‑specific limitations.
- Safety: handling hazardous waste/sludge and compliance with radiation protection regulations.
Applications and who uses it
ISO 18227:2014 is practical for:
- Environmental laboratories performing soil quality and contaminated land assessments.
- Waste characterization and regulatory compliance testing (waste, sludge).
- Remediation contractors and consultants needing rapid elemental screening or quantitative analysis.
- Mining and geochemical labs for bulk elemental composition.
- Manufacturers and service providers of XRF instrumentation developing validated methods and calibrations.
Benefits include rapid multi‑element analysis, flexibility across concentration ranges, and reproducible results when using matrix‑matched calibrations and proper QC.
Related standards
- ISO 11464 - Pretreatment of samples for physico‑chemical analysis
- ISO 11465 - Determination of dry matter and water content
- ISO/IEC 17025 - Competence of testing and calibration laboratories
- EN 14346, EN 15002 - Waste characterization and sample preparation
Keywords: ISO 18227:2014, XRF, EDXRF, WDXRF, soil quality, elemental composition, matrix‑matched calibration, fused beads, pressed pellets, sample preparation, environmental analysis.