Essentially, the Coolgardie Safe is a cupbord made with a wood frame, wire mesh, a galvanized iron tray on top with a hessian bag (canvas) attached from one end into the tray. The safe works by placing it in a shaded, preferably breezy, area. Water is then poured into the metal tray to allow the hessian bag to soak up the water and become saturated. As air passes through the wet hessian bag evaporation occures which cools the passing air and thus cools the food within the safe.