A new choked flow criterion based on the system eigenvalues derived by the characteristic analysis of a hyperbolic nonequilibrium two-fluid model is employed in the RELAP5/MOD3 code. A modification of the choked flow model produced by the earlier works of Trapp and Ransom is elaborated so that better predictions of choked flow rate can be made in the two-phase bubbly flow. Marviken choked flow tests on the large-scale break of pipes are assessed by using the present criterion. The assessment results demonstrate more accurate predictions of choked flow rate in the bubbly flow regime without any adjustment than those of the earlier calculations by using the equilibrium choked flow criterion.