Belgian Reactor 2 - BR2

BR2 reactor buildingThe BR2 reactor was first operated in January 1963. This Materials Testing Reactor is SCK•CEN's most important nuclear facility. It was operated during the past fifty years within the framework of many international programmes concerning the development of structural materials and nuclear fuels for various types of nuclear fission reactors as well as for fusion reactor research.The BR2 reactor also plays an important role for the development and production of materials for nuclear medicine and electronics and (renewable) energy applications worldwide.

BR2 is to undergo a thorough maintenance and modernisation operation until mid-2016. To guarantee a safe and efficient operation, various systems and components will be replaced as a precaution.

Research & Development

The qualities and particular features of the BR2 reactor also allowed experiments to be performed that are aimed at assessing and demonstrating the safety of nuclear cores.

Today, the reactor plays an essential role in the national and international programmes related to:
  • The safety of nuclear reactors, plant lifetime evaluations and ageing of components
  • The safety of nuclear fuels, the increase of their burn-up and MOX fuels
  • The development of new fuels with reduced risk of proliferation of nuclear weapon technology
  • The evolution and assessment of safety problems
  • Production activities related to medical and industrial applications
BR2 core view 

Production of radioisotopes and neutron transmutation doped silicon

Besides its scientific R&D objectives, the BR2 reactor has a second mission: it plays an important role in the support of medicine, by the production of radioisotopes used for diagnostics, the fight against cancer and palliative care. Thus, the reactor is not only used fot scientific research within SCK•CEN's own programmes and for external clients; it is also used for the production of radio-elements and for the production of Neutron Transmutation Doped (NTD) silicon (Si).

BR2 is one of the best performing reactors in the world and it is becoming more important as the number of such research reactors is declining worldwide.

Irradiation services

Neutron transmutation doped silicon

Technical specifications

The capabilities and the design of the BR2 are particularly well suited to R&D options, offering:
  • A core with a central vertical 200 mm diameter channel, with all its other channels inclined to form a hyperboloidal arrangement around it. This geometry combines compactness leading to high fission power density, with easy access at the top and bottom covers, allowing complex irradiation devices to be inserted and withdrawn.
  • A large number of experimental positions of 84 mm with in addition 4 peripheral 200 mm channels for large irradiation devices. Experiments can be installed through penetrations in the top and bottom covers of the vessel.
  • A remarkable flexibility of utilisation: the reactor core configuration and operation mode are adapted to experimental requirements.
  • Irradiation conditions representative of those of various power reactor types - including neutron spectrum tailoring.
  • High neutron fluxes, both thermal and fast (up to 1015 n/cm2.s).
  • Operation cycles of 3 or 4 weeks.



Br2 cross section

Contact: Van Dyck Steven

Projects & Devices

A range of permanent or reloadable experimental devices is available for R&D or production activities. 

  • Experimental rigs for MTR's (BR2, JHR, MYRRHA)  
  • MISTRAL: Multipurpose Irradiation System for Testing of Reactor ALloys 
  • PWC/CCD: Pressurised Water Capsule/Cycling and Calibration Device
  • LIBERTY: LIfting Basket in the Experimental Rig for BR2 Thimble tube sYstem for material irradiation  
  • ROBIN: ROtating Basket with Instrumented Needles
  • SMIRNOF: A versatile in-pile reactor irradiation facility for radiation assessment of optical fibres in fission-reactor environment
  • POSEIDON: Silicon Doping
  • EVITA: Enhanced Velocity Irradiation Test Apparatus for the qualification of JHR driver fuel elements 
  • PRF: a reloadable facility for the production of radioisotopes
  • Nuclear in-pile instrumentation