Blow-Fill-Seal (BFS) technology is a pharmaceutical filling process in which containers are formed from a thermoplastic granulate, filled with product, and then sealed in a continuous, integrated, automatic operation. The two most common types of BFS machines are the Shuttling machine (with Parison cut) and the Rotary machine (Closed Parison) types. The equipment design, operation, and therefore controls for these differ.
For Shuttling systems the processes of container extrusion and filling occur at two separate locations within the machine. The extrusion of the container parison occurs adjacent to the filling zone, the extruded plastic is collected from underneath the extruder head, is cut and formed and automatically transferred (usually by horizontal shuttling) to the filling and sealing zone. For Rotary design machines the filling needles are enclosed within the extruded parison and therefore there is limited exposure of the inner surfaces of the container to the external environment.
Source: GMP Draft Annex 1