ISO 18227:2025

Overview

ISO 18227:2025 - Environmental solid matrices - Determination of elemental composition by X-ray fluorescence spectrometry - provides a standardized procedure for assessing the concentrations of both major and trace elements in homogeneous solid waste, soils, soil-like materials, and sludge. The standard, developed by ISO, covers the use of energy dispersive (EDXRF) and wavelength dispersive (WDXRF) X-ray fluorescence spectrometry for accurate, quantitative analysis, employing matrix-matched calibration standards. Additionally, an optional XRF screening method for solid and liquid materials is included for rapid, semi-quantitative elemental characterization.

This standard addresses the needs of laboratories, environmental monitoring agencies, waste management companies, and researchers, ensuring consistency and reliability in the determination of elements ranging from sodium (Na) and magnesium (Mg) to uranium (U) across a wide concentration spectrum, from as low as 0.0001% up to 100%, depending on the element and instrument capabilities.

Key Topics

• Applicable Matrices and Elements:
  ISO 18227:2025 is designed for homogeneous solid waste, soil, soil-like materials, and sludge. The technique is validated for a range of elements such as 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, and U.

• Analytical Methods:

  • EDXRF and WDXRF spectrometry utilizing matrix-matched calibration
  • Quantitative and semi-quantitative (Annex A) procedures
  • Requirements for sample preparation via pressed pellets or fused beads
  • Calibration methods considering matrix effects and interferences

• Sample Preparation:

  • Procedures for drying, milling, and particle size reduction
  • Preparation of pressed pellets (best for trace and volatile elements)
  • Preparation of fused beads (ideal for non-volatile major and minor elements)

• Quality Control:

  • Use of reference materials and internal standards
  • Drift correction and performance validation
  • Procedures to minimize errors from sample container materials and matrix effects

• Safety and Compliance:
  Adherence to national regulations for hazardous waste handling and radiation safety is emphasized, ensuring the protection of laboratory personnel and environmental integrity.

Applications

• Environmental Monitoring:
  Facilitates reliable analysis of contaminated soil, waste, and sludge for regulatory compliance, remediation planning, and ongoing monitoring efforts.

• Waste Management:
  Supports classification, treatment, and recycling of solid waste by determining the content of hazardous or valuable elements.

• Soil Science and Research:
  Provides essential data for agronomy, geochemistry, and environmental impact assessments regarding elemental concentrations.

• Laboratory Analysis:
  Standardizes methodologies for commercial and government testing laboratories conducting XRF analyses, improving comparability of results across different facilities.

Related Standards

• ISO 11464: Soil quality - Sample pretreatment for physical and chemical analyses
• ISO 12677: Chemical analysis of refractories by XRF - Fused cast-bead method
• ISO 11465: Soil quality - Determination of dry matter and water content
• ISO/IEC 17025: General requirements for the competence of testing and calibration laboratories

ISO 18227:2025 aligns with broader environmental testing and laboratory quality standards, facilitating integration into multi-method analytical workflows.

For organizations, laboratories, or regulatory bodies involved in environmental analysis, compliance with ISO 18227:2025 ensures rigorous, repeatable determination of elemental composition in environmental solid matrices, supporting informed decision-making and environmental protection.