Overview - EN ISO 9698:2019 (Water quality - Tritium - Liquid scintillation counting)
EN ISO 9698:2019 specifies a standardized liquid scintillation counting (LSC) method for determining tritium (3H) activity concentration in water. The scope covers marine waters, surface waters, ground waters, rain, drinking waters and tritiated water in effluents. The method is published by CEN as the European adoption of ISO 9698:2019 and supersedes earlier editions (EN ISO 9698:2015 / ISO 9698:2010).
Key topics and technical requirements
- Principle: Quantification of tritium using liquid scintillation counting after appropriate sample preparation.
- Sample types: Marine, surface, ground, rain, drinking waters and effluent tritiated water ([3H]H2O).
- Limitations: Not directly applicable to organically bound tritium-determination requires additional chemical processing (e.g., chemical oxidation or combustion).
- Detection capability: With suitable conditions, the detection limit may be as low as 1 Bq·l−1. Tritium activity concentrations below 10^6 Bq·l−1 can be measured without sample dilution.
- Standard content: Terms/definitions, reagents and equipment (including LSC counters and vials), sampling and sample storage, sample preparation (direct measurement and distillation procedures), counting procedure, calibration and quench control, expression of results, decision threshold and detection limit calculations, test reporting.
- Annexes: Informative guidance on numerical examples, distillation (small and large volumes), simplified distillation and internal standard methods.
Practical applications and users
Who uses EN ISO 9698:2019:
- Environmental laboratories conducting radioactivity monitoring of water bodies.
- Water utilities and public health agencies testing drinking water for tritium content.
- Nuclear facilities and industrial sites monitoring effluent tritiated water and compliance reporting.
- Regulatory bodies, consultants and researchers involved in radiological assessment and environmental impact studies.
Practical benefits:
- Provides a harmonized, reproducible procedure for tritium analysis, supporting regulatory compliance and public health protection.
- Enables reliable low-level measurements for trend monitoring and incident response.
- Offers validated procedures for sample preparation (including distillation) and quality control (calibration, quench correction).
Related standards and references
- Developed by ISO/TC 147 (Water quality) in collaboration with CEN/TC 230 (Water analysis).
- Endorsed as a European Standard: EN ISO 9698:2019.
- Supersedes prior EN/ISO editions (2015, 2010); users should consult the current edition for updated sampling and preparation requirements.
Keywords: water quality, tritium, EN ISO 9698:2019, ISO 9698:2019, liquid scintillation counting, tritiated water, detection limit, radiological monitoring, drinking water testing.
