Abstract: Racks (20) supported on a transfer cart (38) in a decontamination area (18) are loaded with contaminated articles. The carts are wheeled to a washer (14) into which the racks of contaminated articles are placed for washing. After washing, the racks are removed from the washer in a preparation and packing or clean room (12) and unloaded. The empty racks are moved through a rack return (28) back to the decontamination area. The rack return includes a rack supporting surface (32) on which glide strips (42) are mounted for sliding the racks from the clean room to the decontamination area. Guide strips (44) guide the racks to a pair of vertically pivoted polycarbonate doors (34) which the racks push open by engaging bumpers (58). After the rack has passed through the doors, a self-closure mechanism (60) closes the doors automatically. The rack return assembly includes stops (76, 78) on both sides for aligning a rack carrying cart of any of a plurality of sizes accurately with the rack return assembly.