Analysis of ALPS treated water as third-party



Regulatory standard value

Based on international recommendations, the amount of radioactive materials discharged into the environment from nuclear power stations and other sources is defined as the regulatory standard value for the amount that does not cause any effects on the human body.

More details.

Regulatory concentrations limits, Sum of ratios to regulatory concentrations

The concentration limit of radioactive materials that can be discharged into the environment is defined for each nuclide by the related law (Public Notice)*, which is called a regulatory concentrations limits. If the radioactive material contains multiple nuclides, evaluation will be conducted by adding up the ratios of activity concentration for each nuclide to the regulatory concentration limit. This added value is called the sum of ratios to regulatory concentrations.

*:“Notification Establishing Dose Limits, etc. Based on the Provisions of the Regulations, etc. Concerning the Refining Business of Nuclear Source Material or Nuclear Fuel Material”, Notice by the Nuclear Regulation Authority (August 31, 2015)

The Series of Environmental Radioactivity Measuring Methods

The Series of Environmental Radioactivity Measuring Methods is a manual* established by the government as methods to separate and quantify radioactive materials such as tritium in environment efficiently and accurately.

*“Tritium Analysis”, Ministry of Education, Culture, Sports, Science and Technology (revised in 2002)


In the analysis of ALPS treated water, the analysis results contain variation within certain range (uncertainty). Such variation is basically caused by each factor in the analysis process, such as the methods for sample fractionation, calibration and the usage environment of analysis tools and instruments, and the pretreatment methods. In addition to these factors, the variation is also caused by multiple factors such as human factors like proficiency of the technicians. Therefore, it is required to evaluate the extent of such variation. For the analysis of low concentration samples, since slight differences in factors tend to affect the analysis results, the uncertainty becomes larger. There is no uniform method for identifying factors that should be taken into consideration in evaluating uncertainty. Instead, uncertainty factors will be set based on the analysis method, facility, and analysis skill level by the person conducting the analysis.