We study the problem of computing the vitality of edges and vertices with respect to st-max flow in undirected planar graphs, where the vitality of an
edge/vertex in a graph with respect to max flow between two fixed vertices s,t is defined as the max flow decrease when the edge/vertex is removed from
the graph. We show that a delta additive approximation of the vitality of all edges with capacity at most c can be computed in O(raccdeltan+nloglogn) time, where n is the size of the graph. A similar result is given for the vitality of vertices. All our algorithms work in O(n) space