Mobile tip waste rack and methods thereof

A method of wasting tips in an automated processing module is disclosed, which includes at least three positions for holding sample racks. One of the positions is a tip waste rack position holding a tip waste rack, which includes tip receiving openings. Furthermore, it includes a SWAP rack holding mechanism for temporarily holding a sample rack. The method includes transferring the tip waste rack from the tip waste rack position to an adjacent sample rack position. Once the tip waste rack is placed in the adjacent sample rack position, the error pipette tip is discarded into one of the tip receiving openings of the tip waste rack. Following this, the tip waste rack is transferred back to the tip waste rack position. The sample rack temporarily placed in the SWAP rack holding mechanism is transferred from the SWAP rack holding mechanism to the adjacent sample rack position.