Abstract: A method and a device for detection and removal of one or more misplaced boards (6) on an elevator for the separation of boards (6). The elevator comprises a frame (1) that supports carrier chains (2) that run over pulley wheels (3, 4) and demonstrate carriers (2.1) on which boards (6) are lifted. The elevator comprises removal devices (5.3, 5.4) for misplaced boards (6). Removal of two or more boards that have been lifted together on one row of equivalently placed carriers (2.1) is achieved with the aid of at least one laser-light detector (10.3, 10.4). Laser light is directed towards the long sides of the boards (6) and reflected laser light is received in the relevant detector (10.3, 10.4). The signals from each detector (10.3, 10.4) are processed in a computer and the boards (6) removed from the elevator with the aid of a removal device (5.3, 5.4) if misplaced boards (6) are registered by the computer.