Identification of electromagnetic leakage from seams and joints and their prevention

In the absence of an enclosure manufactured from a monolithic piece of metal, the shielding effectiveness of the realistic enclosures is more often than not limited by the presence of seams and joints. These mating members are the weak spots in an electromagnetically shielded enclosure. Thus, such breach of shield integrity causes EM field leakage from outside of the enclosure to inside and vice versa. The problems associated with such screwed, riveted or welded joints are discussed in this paper along with the different techniques employed to enhance the performance of such enclosures.