Self closing tank lid

In a safety receptacle having a housing part and a lid part, said housing part including a side wall terminating in an upper marginal edge defining an opening in the housing part, a hinge connecting said lid part to said housing part, said lid part being shiftable about said hinge between a closed position spanning said opening and an open position, linkage means operable by a receptacle user for shifting said lid part between said closed position and said open position, said lid part normally being shiftable from its open position into its closed position by the weight of the lid part, the improvement wherein said linkage means includes a linkage member overlying said lid part, a connector carried by said lid part, a heat sensitive actuator means attaching said linkage member to said connector wherein said lid part is shiftable between its open and closed position upon operation of said linkage means, said heat sensitive actuator means for releasing said connector from said linkage member in the presence of a fire when the lid part is held by said linkage means in its open position whereby the lid part can shift into its closed position by its own weight.