Phebus PF, international major programme in nuclear safety: the last test

For the last test Phebus P.F. (the fifth one), it is expected a fast degradation of the boron carbon pencils, leading to a fast release of boron and carbon gas species. Among the carbon gas produced, it is expected to a presence of methane susceptible to interact with iodine to form organic species. The conditions of tests should lead to observe a contribution of containment sump to volatile iodine generation. (N.C.)