The CODEX-B4C bundle test has been successfully performed on 25th May 2001 in the
framework of the COLOSS project of the EU 5th FWP. The high temperature degradation
of a VVER-1000 type bundle with B4C control rod was investigated with electrically
heated fuel rods. The experiment was carried out according to a scenario selected in
favour of methane formation. Degradation of control rod and fuel bundle took place at
temperatures ~2000 oC, cooling down of the bundle was performed in steam atmosphere.
The gas composition measurement indicated no methane production during the
experiment. High release of aerosols was detected in the high temperature oxidation
phase. The on-line measured data are collected into a database and are available for code
validation and development
