Belgian National Data Center for the CTBT

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The Comprehensive Nuclear-Test-Ban Treaty (CTBT) prohibits all forms of nuclear testing worldwide. Belgium ratified the CTBT in 1999. In order to prevent clandestine nuclear testing, the treaty provides for an extensive verification regime. As part of this, more than 300 monitoring stations and 16 laboratories around the world are needed to detect possible nuclear tests, using four scientific methods: seismic, hydroacoustic, infrasound and radionuclides. These techniques permit the detection of nuclear explosions, whether they occur in the atmosphere, underground or underwater.

The information from the monitoring stations is centralized in Vienna, where the treaty organization (CTBTO) is located. The Member States of the CTBT have access to all collected data to assess a suspicious event. To this end, a national data center is being set up in each Member State, which brings together scientists from various sectors to analyze the data.

The data collected by the monitoring stations are not only used for the detection of nuclear tests. The data can have other scientific applications. They are used to send out early warning alerts of approaching tsunamis. They help accurately predict the start of monsoon rains, allowing for better timing of agricultural activities. They are also a source of information about climate change.

Founded in 2019, the Belgian National Data Center was named The analyzes the collected data and facilitates the interaction between the Belgian institutions and the CTBTO.


Activities of the

  • Writing analysis reports on suspicious observations that may indicate a nuclear explosion;
  • Supporting the Belgian contribution to CTBTO activities and meetings;
  • Conducting research in support of the CTBTO;  
  • Participation in simulations and exercises of the CTBTO;
  • International cooperation. In 2019, an agreement was concluded on cooperation and pooling of expertise between the NDCs of the BENELUX countries.


Examples of observations

Data collected by the international monitoring system of the CTBT

The data collected by the international monitoring system of the CTBT is surveilled by the national data centre of a member state to identify possible violations of the treaty. The figure shows the Xe-133, a radioisotope measured by the radionuclide network, activity concentration in the air, collected at a monitoring station in Japan, within 11 weeks after the third nuclear test conducted by the DPRK. The data points in red are suspicious detections that are likely to have originated from the nuclear test.


Atmospheric transport models

Atmospheric transport models can be used to determine the origin of anomalous radionuclide detections. The left panel shows possible source locations calculated from anomalous Xe-133 detections following the third nuclear test conducted by the DPRK. Furthermore, by performing multiple realizations of model runs (this is the so-called ensemble technique), uncertainty information can be obtained (right panel).


Composition of the

The founding members of the are:

  • The Federal Public Service Economy (DG Energy)
  • The Federal Agency for Nuclear Control (FANC-AFCN)
  • The Research Center for Nuclear Energy (SCK CEN)
  • The Royal Meteorological Institute (KMI-IRM)
  • The Federal Public Service Foreign Affairs  

The collaborates with other Belgian scientific institutions associated with its activities. The Royal Observatory of Belgium (ROB) is one of these institutions.


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