Generally described herein are apparatus, systems and methods related to a pre-loaded septum insertable in an access port housing for increasing the control of the compression within the septum and the interference between the septum and the housing. For example, a pair of washers having mating portions may be positioned on respective sides of a rubber septum and bent such that the mating portions of one of the washer are interlocked with the mating portions of the other washer, the interlocked portions forming a tight ring about the septum and generating lateral compression on the septum, thereby “loading” the septum. In addition, fluid seals made of a rubber material with lower durometer than the rubber septum may be used at the interface between the rubber septum and the housing to enhance the fluid sealing functionality while promoting the self-sealing features of the rubber septum.