A series of MAAP3.0 calculations was made with varying parameters to simulate a postulated large-break loss-of-coolant accident at the Kuosheng plant with a boiling water reactor-6 and MARK III containment. Analyses showed that uncertainties in the corematerial eutectic temperature and the degree of flow blockage will result in a large uncertainty in the predicted in-vessel hydrogen generation. The pressure variations caused by hydrogen burns, which are related to the preceding in- and ex-vessel hydrogen generation, may force some suppression-pool water into the pedestal cavity where most of the corium remains. This will further affect the possibility and the extent of corium/concrete interactions and thus the rate and the amount of ex-vessel hydrogen generation. Burns would occur at a very low hydrogen concentration if the compartment (gas) temperature were high and the flame temperature criteria were used for burn determination. If burns were to occur after containment failure, the hydrogen burns could have a significant impact on the release of fission product to the environment.