Pan size, shape, baffles and angle Spray nozzle diameter, Air cap design Drying air system Exhaust air system A slight negative pressure inside pan Stirring mechanism for bulk suspension Good air handling unit for the area Flame and explosion proofing where ever necessary Tablets High hardness Low friability Good surface adhesion property Coating Suspension Stir 40 - 50 mins prior to spraying Low particle size of suspended pigments & opacifiers Low settling rates Good flowability Process Variables Tablet load size Pan RPM Quantity and temp. of drying air Quantity and temp. of exhaust air Tablet bed temp. Profile Atomisation pressure The spray rate The spray pattern The spray distance