Some observations on airborne particles in blow-fill-seal filling rooms

Pharmaceutical products produced by blow-fill-seal (BFS) technology are manufactured in clean rooms of different cleanliness classes. Regulatory authorities set requirements on factors such as the maximum allowed airborne particle concentration in filling rooms with BFS machines. To meet the requirements of the authorities, the supply air is HEPA-filtered. The necessary flow of HEPA-filtered air depends on the particle generations from the BFS machines (source strength). One method of reducing the airborne particle concentration in the filling rooms is to install local exhaust systems in order to remove generated particles. Knowledge of particle dispersion and source strength are necessary to enable correctly dimensioned airflows. In this paper, the dispersion pattern of particles was studied at one filling machine. The partial source strength was determined for four different filling machines. The source strength is the total number of airborne particles per second generated by the BFS machine and the process. The value of the partial source strength will be dependent on the efficiency of the local exhaust system. Partial source strength is defined as the estimated theoretical quantity of particles per second emitted from the filling machine into the filling room. The results show that the partial source strength varies widely between the different filling machines. The source strength levels vary between 10(2) and 10(7) particles (> or = 0.5 microm) per second. Furthermore, the results show that the efficiency of the local exhausts can be improved by design adjustments.