Radionuclide Laboratory RL03, Seibersdorf, Austria

Radionuclide Laboratory RL03,
Seibersdorf, Austria

Thumbnail profile: Lower Austria

Lower Austria is one of Austria’s nine federal states. With a land area of almost 20,000 km² and a population of 1.6 million, it is Austria’s largest state. In terms of population, it ranks second only to Vienna, which also is a federal state but is completely encircled by Lower Austria.

Geography and Climate

The name Austria means "eastern realm" and is derived from the Old German word Ostarrîchi.  “Lower” Austria designates where this state is situated on the Danube River, which flows from west to east . This state borders on Slovakia, the Czech Republic and the other Austrian states of Upper Austria, Styria and Burgenland.

Although Austria is mountainous, the high alpine chains to the west gradually recede as one travels eastwards down into the Danube Valley, Lower Austria and onwards towards the country’s capital, Vienna.

In the east of the country, in the Pannonian Plain and along the Danube valley, the climate shows continental features with less rain than the alpine areas. Although Austria is cold and snowy in winter, summer temperatures can be rather warm, reaching 35ºC.

Laboratory Location

Radionuclide laboratory ATL03 is located in the small town of Seibersdorf in the province of Lower Austria, about 35 km southeast of Vienna, on the premises of the Austrian Research Centers, Seibersdorf (ARCS). ATL03 is part of the radionuclide network making up the CTBTO's International Monitoring System (IMS).

This site was dedicated by the Austrian Government as a nuclear research centre soon after the country re-acquired its post-World War II independence in the mid-1950s. The aim was to designate a site close enough to Vienna to accommodate commutes to/from the city while still remaining outside the city limits. The first operating licenses were granted in 1958. The International Atomic Energy Agency (IAEA) also has its laboratories here, adjacent to the ARCS complex.

ARCS hosts other nuclear research fields as well, such as biogenetics, biomedical engineering, energy, radiation safety and applications, life sciences, nano-system technologies, nuclear engineering and technology transfer.


ATL03 is the only IMS facility located on Austrian territory. Austria is host to the CTBTO's headquarters in Vienna.


Learn more about Austria and the CTBT.

Laboratory Profile

ATL03 is located within the Health Physics Division of the Austrian Research Centers. A company that is majority-owned by the Republic of Austria, ARCS’s purpose is to conduct research and provide services in a broad range of technological areas. In terms of the CTBTO's Provisional Technical Secretariat (PTS), the primary task of these laboratories is to provide analyses of samples from the radionuclide network.

As regards ATL03’s analytical systems, the laboratory is certified to perform gamma spectrometry measurements. Gamma spectroscopy is a method used to measure radionuclides. Unlike a Geiger counter that determines only the count rate, a gamma spectrometer determines the energy and the count rate of gamma rays emitted by radioactive substances.

The detection system established for IMS sample analysis comprises a hyper-pure germanium (HPGe) detector, a state-of-the art instrument to measure radioactivity. The detector and shielding are contained in a purposely built enclosure within a room that is dedicated to CTBT-related functions. The associated electronics and computer system for spectral acquisition and analysis are in the same room. Access to these areas is restricted to personnel authorized to carry out IMS analyses.

Testing, Evaluation and Certification

The service provided to CTBTO also includes: dedicated communication through a Very Small Aperture Terminal (VSAT), data authentication, and sample handling. Transport of samples between a radionuclide station and the Austrian laboratory is done following appropriate procedures to ensure optimum sample safety and tracking. Special seals are used to guarantee the sample’s physical integrity.

An on-site certification visit took place in May 2001. The certification team responsible for ATL03 assessed the facility for compliance with the certification requirements to conduct the analyses of IMS samples by means of non-destructive, high-resolution gamma spectroscopy.

It is considered an extremely important method because most radioactive sources produce gamma rays and when these emissions are collected and analyzed with a gamma spectroscopy system, a gamma energy spectrum can be produced.

Detailed analyses of these spectra are typically used to determine the identity and quantity of gamma emitters present in the source. With this method, the laboratory can determine whether certain radioactive particles stem from a nuclear explosion or from other sources.

Having carried out the technical assessments, the certification team determined that ATL03 met the certification requirements under the Treaty. Thus, the Seibersdorf Facility was certified on 8 November 2001 and enjoys the distinction of being the first radionuclide laboratory to be certified as an IMS facility.


Learn more about how the radionuclide technology works.