Abstract: A safety pressure relief device having a rupture disc with a conical central portion. The relief device comprises inlet and outlet support members wherein the rupture disc is positioned therebetween. The rupture disc has an annular outer flange portion with a conical central portion disposed radially inwardly therefrom. When positioned in the relief device, a tip of the conical portion is directed toward the inlet support member. Scoring is provided on the conical portion for defining at least one line of weakness thereon. In one embodiment, a plurality of linear scores extend radially on the conical portion and are spaced from the tip and base thereof. In another embodiment, the scoring includes a curvilinear score forming an incomplete circle adjacent the base, either spaced therefrom or contiguous therewith. With all embodiments, the rupture disc is adapted for rupturing at relatively low pressures without fragmentation.