Design, development and qualification of a microbiological challenge facility to assess the effectiveness of BFS aseptic processing.

A programme of work has been initiated to further the understanding of the impact of the environment surrounding a Blow/Fill/Seal (BFS) machine upon the microbiological quality of processed product. A dedicated facility (Challenge Room) has been constructed and qualified to provide for the production and containment of dispersions of micro organisms in air of a room housing an operating BFS machine of a given style and configuration. The facility achieves homogeneous distribution of generated dispersions throughout the Challenge Room air, including that within and close to the critical area in which aseptic BFS operations occur. Generated microbial dispersions can be maintained in the room over extended time periods (up to 600 min) at a desired concentration within the range 10(1) to 10(7) cfu m(-3). They can also be produced employing different cell types, including bacterial endospores, Gram-positive and Gram-negative vegetative cells and yeast cells. Effective containment of dispersions is achieved while 'cards of product' (vials in sets) are conveyed from the Challenge Room to an adjacent Packing and Storage Area. Decontamination of the room and the housed BFS machine is accomplished through exposure to chlorine dioxide gas at a concentration of 1.0 mg dm(-3) for 120 min at room temperature (approximately 23 degrees C).