EN ISO 22515:2021 PDF

Overview

EN ISO 22515:2021 / ISO 22515:2021 specifies a standardized laboratory method for determining the activity concentration of the radionuclide iron-55 (55Fe) in all types of water using liquid scintillation counting (LSC). Endorsed by CEN, this test method is intended for environmental and radiological water monitoring and provides procedures from sample preparation through measurement, calibration, calculation and reporting.

Key topics and requirements

• Scope and applicability: Measurement of 55Fe in surface water, groundwater, seawater, drinking water and effluents using LSC. Laboratories are responsible for verifying method suitability for their samples.
• Measurement range: With commonly available liquid scintillation counters, activity concentrations from the limit of detection up to ~120 mBq·L⁻¹ can be measured.
• Typical measurement parameters: Achievable performance reported for counting times between 7 200 s and 10 800 s and sample volumes 0.5–1.5 L; higher activities can be measured by dilution or smaller aliquots.
• Dependence on matrix and equipment: Detection limits and performance are influenced by the amount of stable iron, dissolved material in the water, counter background count rate, and counting efficiency.
• Technical content covered:
  • Principle of LSC measurement for 55Fe
  • Required reagents and carriers (stable iron, quench agents)
  • Sample collection, preparation and chemical separation/isolation of iron
  • LSC setup: region setting, background determination, calibration and detection efficiency
  • Quality control measures, iron recovery assessment, decision threshold and detection limit calculations
  • Expression of results and required test report items
• Supplementary material: Informative annexes include iron isolation/purification procedures and an analysis flow chart.

Practical applications and users

• Environmental and radiological monitoring programs tracking radionuclide contamination in water.
• Laboratories performing compliance testing for regulatory agencies, nuclear facilities, coastal and marine monitoring programs.
• Research institutions studying radionuclide transport, isotope behavior and environmental radioactivity.
• Water utilities and consultants assessing radiological quality of drinking water and effluents.

Related standards and references

• EN ISO 22515:2021 is the CEN-adopted version of ISO 22515:2021.
• Users should consult other ISO/CEN water quality and radionuclide measurement standards and national regulations for sampling, reporting and laboratory accreditation requirements.

Keywords: EN ISO 22515:2021, ISO 22515, Iron-55, 55Fe, liquid scintillation counting, LSC, water quality, radionuclide measurement, detection limit, activity concentration.