Find an open room where trays can be stored without being too near the walls or the ceiling. Walls are going to have varying microbial and insect life near them, the ceiling may leak. Even in secure environments, both areas are weak points to a room’s sterility. Consider tray idiosyncrasies as well. There are certain trays that cannot be stacked one atop the other, as they’ll end up compromising each other’s sterility. The last thing to consider is how accessible said packages are. You’re going to need to monitor them before they go to surgery.