Plasma Surface Interaction (PSI) effects on plasma burn-through are compared for the carbon wall and the ITER-Like Wall (ILW) at JET. For the carbon wall, the radiation barrier and C2+ influx have a significant linear correlation whereas the radiation barrier in the ILW does not have such a linear correlation with Be1+ influx. The JET data are explained by the simulation results of the DYON code. The radiation barrier in the carbon wall JET is dominated by the carbon radiation, but the radiation barrier in the ILW is mainly from the deuterium radiation rather than the beryllium radiation.