Abstract: An improved rupture disk assembly for a pressure relief system is disclosed. The rupture disk assembly is sealed between an inlet support member and an outlet support member, each of which define a central fluid pathway. A rupture disk that includes a flange connected to a dome-shaped rupturable portion by a transition area is sealed between the support members. The rupturable portion may include an indentation positioned at the apex of the dome and a score line having a first and a second end. A safety member that has a hinge including a knuckle and a tongue is positioned between the rupture disk and the outlet support member. The knuckle extends downwardly into the dome and extends laterally across the dome to a point that is inside the area circumscribed by the score line or inside the area circumscribed by an arc connecting the two ends of the score line.