The reactor building is 32m high and has the shape of a 40m x 40m square in its lower section and of an octagon in its upper part. It contains the beam tube reactor and all installations for being able to do research with neutrons. The reactor building includes the experimental hall with its instruments.
The neutron guide hall joins the reactor building - it is a hall of approx. 55m x 30m. It offers more area for experimental equipment and contains the major share of all instruments. Moreover the hall is ideal for experiments sensitive to background radiation due to the distance to the reactor.
The neutron guide hall occupies the space between the new and the old reactor - the Atomic Egg. The building of the old reactor offers additional place for experiments and experiments involving outstanding length may be extended into its area.
A second guide hall will house the target station of the fission accelerator and a station for neutron radiography and tomography. This hall will probably only be commissioned a few years after the start-up of the reactor.

Besides its function as a container for the experimental equipment the reactor building meets the high requirements of security. It provides full protection against earthquakes, airplane crashes, explosions, lightning discharge and flood - a new and unique feature worldwide for research reactors. Moreover special equipment is installed preventing the discharge of radioactive matter.