Background note for the fifth
anniversary of the Provisional
Technical Secretariat (PTS)

The Provisional Technical Secretariat of the Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) celebrates its fifth anniversary this year. On 17 March 1997, the Secretariat started work in Vienna with a handful of staff members under the Executive Secretary, Mr. Wolfgang Hoffmann. Today, the organization has developed into a fully-fledged international Secretariat with 271 staff members from 69 Member States, successfully implementing an ambitious plan to establish a global verification regime to monitor compliance with the Comprehensive Nuclear-Test-Ban Treaty (CTBT). The Secretariat provides technical, analytical, legal, operational and administrative support to the Member States. Comprehensive Nuclear-Test-Ban Treaty The opening for signature of the Treaty on 24 September 1996 was the culmination of more than 40 years of negotiations aimed at bringing to an end nuclear test explosions in all environments. The CTBT is not only recognized for its role in bringing to an end a period that witnessed over 2000 nuclear test explosions worldwide, but also for its contribution to nuclear non-proliferation and nuclear disarmament and the enhancement of international peace and security. The Treaty enjoys the support of an overwhelming majority of the international community, which is evident in the 165 signatures and 90 ratifications it has attracted to date. This includes ratifications by 31 of the 44 States listed in Annex 2 to the Treaty, whose ratification is necessary for the Treaty to enter into force. CTBTO Preparatory Commission Two months after the Treaty was opened for signature, the Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization was established on 19 November 1996 at a meeting of States Signatories at the United Nations in New York. It focuses its activities in two areas: the establishment of a global verification regime which must be capable of detecting nuclear explosions underground, in water and in the atmosphere, and the promotion of Treaty signature and ratification. In carrying out its functions, the Commission is assisted by the Provisional Technical Secretariat.

Main elements of the verification regime The verification regime consists of an International Monitoring System (IMS) supported by an International Data Centre (IDC), and a consultation and clarification process to clarify and resolve matters concerning possible non-compliance with the basic obligations of the Treaty. As a final verification measure, on-site inspections are provided for in the Treaty to clarify whether a nuclear explosion has been carried out in violation of the Treaty and to gather facts which might assist in identifying a possible violator. Lastly, confidence-building measures contribute to the timely resolution of compliance concerns arising from possible misinterpretation of verification data relating to chemical explosions, and to the calibration of the IMS. International Monitoring System The IMS comprises a global network of 321 monitoring stations and 16 laboratories located in some 90 countries around the world. Four verification technologies - seismic, infrasound, hydroacoustic and radionuclide - are used to monitor the Earth for evidence of a nuclear explosion. Since the establishment of the IMS network began in 1997, important progress has been achieved. The site survey programme is rapidly approaching conclusion, with 84% of the site surveys now completed. In the past year, 24 additional stations were installed and 12 more facilities, including the first radionuclide laboratory, were certified. This brings the total number of stations meeting all the technical requirements of the Preparatory Commission to 24. By the end of February 2002, installations had been completed at 122 stations. Currently a total of 55 stations in the four technologies and 20 additional auxiliary seismic station are under construction. During 2001 the Commission also began to lay the groundwork for the operation and maintenance of IMS stations.

International Data Centre (IDC) and Global Communications Infrastructure (GCI) The data transmitted by the IMS stations through the Global Communications Infrastructure are processed and analysed in the IDC. Together with other IDC products relevant for Treaty verification, the data are then released to Member States for judgement. By the end of 2001, 53 secure signatory accounts had been established, with a total of 387 authorized users. On average, 21,000 IDC products are being made available to authorized users each month. Managed by the IDC Division, the GCI is the first global satellite communications network based on very small aperture terminals (VSATs) technology. Designed to be cost-effective and to provide data within seconds from origin to final destination, the network became functional in mid-1999. The GCI coverage continued to expand in 2001 with the installation of 42 additional VSATs. As of February 2002, 150 GCI site surveys had been completed and VSATs installed at 87 IMS stations and/or National Data Centres.

On-Site Inspections (OSI) The major elements of an OSI regime are the Operational Manual, inspectors and equipment. The Preparatory Commission has given high priority to the development of the OSI Manual, and an initial draft rolling text of the Manual was completed in 2001. To strengthen practical knowledge about OSI activities, field experiments were held in Kazakhstan (1999) and in Slovakia (2001) to test passive seismic equipment for aftershock monitoring, as well as equipment related to other techniques. A workshop was held in Beijing from 15-19 October 2001, focusing on OSI field experiments and tabletop exercises. The Commission has also acquired inspection equipment for training and testing purposes and has held several training courses for inspectors. International Cooperation Under the terms of the Treaty, States Signatories undertake to promote cooperation among themselves and to facilitate information-sharing. This enables States Signatories to strengthen national implementation of verification measures and to benefit from the application of verification technologies for civil and scientific purposes. The verification regime provides a comprehensive set of information about the Earth’s crust, seas and atmosphere, using state-of-the-art technologies. In addition, the Commission offers assistance to Member States in the establishment of National Data Centres (NDCs) and provides access to the Experts Communication System (ECS). International cooperation is thus an important vehicle through which States may maximize benefits of membership in the Treaty regime. The Preparatory Commission has organized a wide range of international cooperation activities such as workshops and training programmes. International cooperation workshops have been held in Vienna (Austria), Cairo (Egypt), Beijing (China), Lima (Peru), Istanbul (Turkey) and Dakar (Senegal). A seminar on CTBT legal and technical issues for States in the Pacific was held in Wellington (New Zealand) as part of the United Nations Asia Pacific Regional Disarmament Conference. In total 128 States have taken part in the workshops and have actively contributed to advancing understanding of the Treaty and to enhancing national capacities in CTBT verification related areas.

For further information on the CTBTO, please see or contact:
Annika Thunborg, Chief, Public Information  
T    +43 1 26030-6375  
E    [email protected]
M    +43 699 1459 6375