Food, beverage and pharmaceutical manufacturers regularly use blending of ingredients as part of their production process. This can apply also to chemical, rubber, and confectionery production. Blending usually occurs in a vessel, often of stainless steel construction which may be heated. There will be internal agitation or even rotation and tumbling of the vessel to apply a stirring action. The moment when ingredients are added is when the greatest risk to plant hygiene occurs as a vessel lid will be open at this time. The risk is of ingredient dust escaping is controlled when the vessel is kept under a slight suction by the connection of an extraction duct connected to a fume / dust extraction system. The RotoClone W and RotoClone N are ideal collectors especially if wet or sticky vapors are involved. If the blending applies only to dry powders then OptiFlo RC would be appropriate.