For small coating drums, a single nozzle may be sufficient to cover the surface of the tablet bed. However, for larger, longer drums, multiple nozzles must be used to spray coating solution on to the surface of the bed, as shown in Fig. 6 and Fig. 7. When multiple nozzles are used, the sprays are located so they just touch each other. If they overlap, then local saturation may occur that may give rise to the formation of inter-particle bridges resulting in product agglomeration. This phenomenon may result in the formation of tablet doublets referred to as “twinning”. Alternatively, local wetting may result in the partial transfer of coating from one tablet to another giving rise to coating defects and unacceptable appearance. On the other hand, if the nozzles are too far apart coating uniformity will be adversely affected since some solids will not receive coating as they cascade down the surface of the bed. In general, spraying onto the top part of the bed is desirable to give maximum drying. However, if fill levels are low and baffles protrude through the bed then the spray zone should be focused at the middle of the bed to avoid depositing coating material on the surfaces of the baffles.