FAQs
Nuclear Testing
Who are the nuclear weapon States?
When did the nuclear weapon States test for the last time?
Have the five nuclear weapon States ratified the CTBT?
How many nuclear tests were conducted in the world before the CTBT opened for signature in 1996?
What was the name of the United States’ initial nuclear testing project and how did it evolve?
What was the only time that nuclear bombs have been used?
What was the world’s biggest nuclear bomb?
In which decade were the most nuclear tests conducted?
In which single year were the most nuclear tests conducted?
Are there other countries beside South Africa that have voluntarily relinquished their nuclear arms?
What is the Mutual Defense Agreement between the United Kingdom and the United States?
Where did France conduct its nuclear tests?
Which Nuclear Weapon State has articulated a “no first use” pledge?
Where have the major nuclear testing sites been located?
What provided a real-life opportunity to test the CTBTO’s global alarm system?
Treaty History
What was the “Atoms for Peace” programme?
Which statesman proposed an end to nuclear testing for the first time?
When was the idea of a nuclear-test-ban verification system first conceived?
Why was the 1963 Partial Test Ban Treaty (PTBT) important?
What was the PNET and what was its purpose?
How was nuclear testing progressively stopped, starting in the 1990s?
When did the Comprehensive Nuclear-Test-Ban Treaty open for signature?
When will the Comprehensive Nuclear-Test-Ban Treaty enter into force?
The CTBT, Signature and Ratification
What is a Treaty-based organization?
How does a State deposit its instrument of ratification?
How does a State become a member of the CTBTO?
How does a State become an accredited observer state?
How does a State sign the Treaty?
How does a State ratify the Treaty?
If a state signs but does not ratify the Treaty, what are they legally bound to?
What are the benefits of being a ratifying State of the CTBT?
What are the benefits of being a Signatory State of the CTBT?
What is the instrument of ratification?
The Organization
When was the CTBTO Preparatory Commission established and what is its main aim?
What is the difference between the CTBTO Preparatory Commission and the CTBTO?
What is the relationship between the CTBTO and the United Nations?
When will the Treaty enter into force?
What is the composition and structure of the CTBTO Preparatory Commission?
How are the activities of the CTBTO funded?
What is the split currency system all about?
What is the Provisional Technical Secretariat (PTS)?
What does it mean that the “PTS is mainly a technical organization”?
What are the working and official languages of the CTBTO?
What are the main criteria for working at the PTS?
What will be the main development once the Treaty enters into force?
International Monitoring System
What exactly is the global Verification Regime?
What comprises the Verification Regime’s International Monitoring System (IMS)?
In selecting the IMS technologies, was there consensus from the beginning?
What technologies and how many of each type were finally selected?
What kinds of challenges had to be overcome in building-up the IMS, starting in the late 1990s?
Can any State request International Monitoring System (IMS) data on any other State?
Exactly where are the monitoring stations located?
As set out in the Treaty, which countries have the most monitoring stations?
What countries have radionuclide laboratories?
How many monitoring stations and radionuclide laboratories are there at present?
How long will it take to install the complete International Monitoring System?
Who operates and maintains the International Monitoring System (IMS) stations?
Why are there so few hydroacoustic stations when the earth is primarily water?
What does infrasound detect that the other three technologies cannot?
What is the difference between a radionuclide laboratory and radionuclide station?
How can a nuclear explosion be verified?
Can the International Monitoring System data be used for any other purposes?
On-Site Inspections
What is an on-site inspection?
Why are on-site inspections called the final verification measure?
Can an on-site inspection be requested before the Treaty enters force?
Can a State refuse an on-inspection and, if so, what would be the result?
How long will an on-site inspection take?
How is an on-site inspection requested?
Who decides that an on-site inspection request is granted?
How large is an inspection team and who are its members?
How is the inspection area defined?
Can an inspected State Party restrict access during an on-site inspection?
