The Comprehensive Nuclear-Test-Ban Treaty (CTBT)


To date, over 2000 nuclear weapon tests have been carried out worldwide. The most recent test was conducted by North Korea in September 2017. It is therefore all the more urgent for the CTBT to enter into force as soon as possible. The Federal Government is doing its utmost to achieve this end.

Nuclear test
Nuclear test© Trinity Atomic Web Site

Every nuclear test is one too many – more than 2000 such tests have been carried out worldwide since 1945. The large number of tests led to the rapid development of this weapons technology, with the explosive power of a single bomb rising exponentially over the decades. “Tsar Bomba”, for example, detonated by the Soviets in 1961, was around 4000 times more powerful than the two atom bombs that were dropped on Japan in August 1945, claiming thousands of lives and rendering vast tracts of land uninhabitable. The German Government is therefore committed to ensuring that nuclear tests are prohibited around the world and that the tests conducted by North Korea since 2006 remain the last of their kind. This is also the objective of the Comprehensive Nuclear-Test-Ban Treaty (CTBT).

Ratification Status

The Treaty was adopted by UN Resolution 50/245 on 10 September 1996 and opened for signature by all states two weeks later, on 24 September 1996. Since being drawn up, it has been signed by 183 states, 166 of which have ratified it. The CTBT can only enter into force, however, when it has been ratified by all 44 states listed in Annex 2 of the Treaty. These are the states that possessed some degree of nuclear technology when the Treaty was being negotiated. Eight of these Annex 2 states have yet to ratify, namely Iran, Israel, Egypt, China, the United States, India, Pakistan and North Korea. The latter three have not yet signed the Treaty. They are also the only three states to have conducted nuclear tests since the CTBT was opened for signature in 1996.
Alongside Australia, Canada, Finland, Japan and the Netherlands, Germany is part of the Friends of the CTBT, a group that is strongly committed to ensuring that the Treaty enters into force.

A global monitoring system – for civilian purposes

Established to implement the Treaty, the Comprehensive Nuclear-Test-Ban Treaty Organization or CTBTO is based in Vienna. It operates on a provisional basis pending the Treaty’s entry into force. The CTBT provides for a global monitoring system to verify compliance with the test ban. Thanks to its International Monitoring System with over 300 monitoring stations (including 16 laboratories) to record seismic, infrasound and hydroacoustic variables as well as radionuclides, CTBTO is already in a position to detect even small underground nuclear detonations around the world. Five German monitoring stations are part of this system – two seismological and two infrasound stations operated by the Federal Institute for Geosciences and Natural Resources, as well as a radionuclide station operated by the Federal Office for Radiation Protection (BfS). With around 6.3 million euros in 2018, Germany is the fourth-largest contributor (assessed contributions) to the CTBTO budget after the US, Japan and China.
After the tsunami of 26 December 2004, the stations began to make their data available for civilian and research purposes as well. As in the case of the March 2011 earthquake and tsunami disaster in Japan, the CTBTO now also routinely transmits its monitoring data to disaster early warning organisations.

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