Our staff: over 260 people from about 70 State Signatories

Working at the Provisional Technical Secretariat

The Provisional Technical Secretariat (PTS)

Former Executive Secretary Lassina Zerbo (left), Former Executive Secretary Tibor Tóth (middle) and Former Executive Secretary Wolfgang Hoffmann (right).

The PTS started its work in Vienna on 17 March 1997 under the auspices of Executive Secretary Wolfgang Hoffmann. He was succeeded by Tibor Tóth on 1 August 2005. On 1 August 2013, Lassina Zerbo became the organization’s third Executive Secretary. The fourth Executive Secretary, Robert Floyd, took office on August 1 2021. The Executive Secretary is the only PTS official appointed by the Commission and reports directly to the Commission on PTS operations.

The main function of the PTS is to assist the Preparatory Commission in the establishment of a global <lex>verification</lex> <lex>regime</lex> to monitor compliance with the comprehensive ban on explosive nuclear testing. This regime – sometimes referred to as a "global alarm system" – is being built up so that it will be operational as soon as the Treaty enters into force. Another PTS function is to promote the signing and <lex>ratification</lex> of the Treaty so that it enters into force as soon as possible.

The PTS staff is multinational in composition. However, only nationals of Signatory States are eligible to serve in the PTS.

The main function of the Provisional Technical Secretariat is to assist the Preparatory Commission in the establishment of a “global alarm system”, which will monitor compliance with the Treaty.

Working at the Provisional Technical Secretariat

Only nationals of Signatory States may work at the PTS.

The Organization considers its staff and their expertise to be its most important resource. The PTS is a non-career organization which means that there are limitations on the number of years that Professional staff may serve there.

There are two main categories of PTS staff:

Professional and General Service Staff.


Working at the PTS cont.

Professional-level (P) staff often come from backgrounds in the scientific, technical, academic or managerial disciplines; they may also be diplomats or international civil servants. These staff members are hired both internationally and locally (i.e. in Austria).

Staff members in the General Service (GS) category are locally recruited and usually provide support services. Within the GS category there are also a limited number of positions that  require international recruitment because the qualifications sought are hard to find. In such cases, internationally recruited GS staff may enjoy many of the P staff benefits. For example, their travel to Vienna upon appointment is paid by the organization and they are also entitled to home leave every two years, as well as education grants for their children.

Staff and the expertise they possess are the organization’s most important resource. Due to the technical nature of the organization, most work opportunities are either in the scientific or technical fields.

Staff members working at the PTS are subject to the CTBTO Staff Regulations and Rules, which outlines their conditions of service, as well as their basic rights, duties and obligations.

Under certain circumstances the PTS employs consultants; that is, a person, a consulting firm or an organization hired to carry out a clearly defined task. It also employs short-term staff to provide secretarial, clerical and administrative assistance when needed. Short-term staff can only be recruited locally (i.e. within Austria). Neither consultants nor short-term staff are considered regular staff and are thus only employed temporarily by the PTS. 

The PTS also offers a limited number of unpaid internships yearly. Prospective interns are usually under 30 years of age, are advanced in their studies towards a university degree or have already obtained a degree. As with consultants and short-term staff, they are also not considered as regular staff and are taken on only as/when the need arises.

Areas of work

International Data Centre (IDC) control room, part of the Operations Centre.

As the PTS is primarily technical in nature, it employs mostly staff with scientific and technical skills. Examples of interesting PTS jobs include work as seismologists, engineers, computer analysts, data analysts, infrasound, radionuclide and hydroacoustic officers and methodology officers, as well as an array of technicians.


Staff carry out various tasks, such as site surveys of prospective stations, as well as the build-up of seismic, infrasound, hydroacoustic and radionuclide stations. They can be analysts or technicians, handling the data that these stations register or preparing various field exercises, such as on-site inspection exercises.

Auxiliary Station AS106, Palmer Station, Antarctica

Many times staff have to travel to very remote, far-flung places or face hazardous situations in the course of carrying out these various tasks. Examples of remote places where IMS stations are under construction or negotiation include remote islands in the Atlantic and the Pacific oceans and on the continent of Antarctica.

Ship laying cable for hydroacoustic station HA04, Crozet Islands.

These staff members who are sent on duty travel also have rare opportunities to experience nature’s pristine beauty. For example, in the Crozet islands in the Southern Indian Ocean, IMS technicians laying cables for a hydroacoustic station in the spring of 2003 had occasion to marvel at the presence of some 25 million penguins that call these islands home. Staff also work with and meet people of many different nationalities, as well as experiencing vastly different cultures in the course of their travels.

For more read this story of a Radionuclide Officer's experience working in the field.

Still other PTS staff work behind the scenes to ensure that the activities of the organization continue to run smoothly. These include writers and editors, lawyers, computer specialists, information professionals, accountants, financial experts and conference service staff all working towards the same goal—that is, a world free forever of nuclear testing.

In terms of language skills, CTBTO staff are typically multi-lingual. This means that they speak two or more of the UN official languages (i.e. Arabic, Chinese, English, French, Russian, or Spanish).

Although the CTBTO has a presence in some 90 countries around the world, its daily business is usually carried out in English.

The daily business of the CTBTO is usually carried out in English, but knowledge of other UN languages is considered an asset. This is because the organization has a presence in some 90 countries around the world, most of them accustomed to languages other than English. Of course, at the Vienna-based PTS, knowledge of German is an additional asset, both for professional contacts and for life outside of office hours. Besides having well-balanced personalities and good communication skills, experience in a cross-cultural work environment is always considered an asset.

Next chapter: Geographical and gender distribution