<p>A spraying system comprises a conveyor for conveying a series of boards (5) through a spraying station with nozzles (13, 14, 15) and means for controlling spraying from the nozzles onto the board at the spraying station. The control means comprises a sensor (3) for sensing the speed of the conveyor, a photoelectric cell (4) for sensing the presence of a board (5) on the conveyor and a logic unit which includes means for calculating the length of the board in response to signals from the sensor (3) and photoelectric cell (4). The logic unit activates the spraying means when the leading edge of the board reaches the spraying station and the nozzles are reciprocated across the conveyor as the board is advanced. Sensors (11, 12) control the nozzles so that spray is delivered only onto the board and is stopped as the nozzles reach the side edges of the board. The system is primarily intended for the flux spraying of printed circuit boards but is not restricted to this use. <IMAGE></p>
