Abstract: Apparatus for housing a rotatable disk used in an information storage apparatus having a disk as the memory storage member. The housing comprises a disk cartridge for holding the disk, the disk cartridge having an aperture which allows the transducer to access the disk, and further comprises a contamination shield interposed in the aperture for smoothing air flow through the aperture. In the absence of the shield, vortices of air form at the aperture which sweep air-borne contaminants into the cartridge and thereby expose the disk to contamination. The shield prevents the vortices from forming, thus eliminating a major cause of disk contamination.