A modular system of medical article containers is used to form enclosures of selectable storage space. The containers are each RF shielded and include an interconnect wall for connecting to another container to form the enclosure. The interconnect walls have a complementary design. The interconnect seam of two containers includes an electrically conductive component that also interconnects the RF shields of the two containers together. The interconnect seam also includes a tortuous path seal for greater RF shielding of the enclosure. The walls of the containers include a substrate of non-electrically conductive material for weight reduction and an electrically conductive element that is coextensive with the substrate. One embodiment is a plastic substrate with a metallic mesh. The enclosure provides a Faraday cage about the interconnected containers. Enclosures of differing heights and sizes can be made, and they may be stacked or otherwise assembled.