In this study, the present state of the air cleanliness in the drug preparation room at a hospital pharmacy was evaluated, and factors affecting airborne particle numbers (APN) such as the number and the movement of workers and the materials on working clothes and cloths were investigated. In addition, the effect of environmental conditions on air cleanliness on a clean bench was compared. APN was measured with an Aerosol Particle Counter.
The maximum 0.5μm APN values while working in the aseptic preparation room were 3, 610, 1, 312 (less than 10, 000 in GMP) and the non-aseptic room were 8, 008, 2, 660 (less than 100, 000) respectively. The conditions of all rooms were sufficiently suitable for drug preparation according to the criteria of GMP.
Concerning factors affecting APN, the movement of workers increased the APN much more than the number of workers. The degree of dispersing particles differed greatly depending on the materials of the working clothes and cloths. A decrease to less than 1 /100 can be obtained by the selection of suitable materials for working clothes such as Overall made of polypropylene non-woven fabric from which few of fibers disperse. It is remarkable that smaller particles are dispersed from clothes even after passing through an air shower. In addition, it was confirmed that the dispersing of particles from cloths and rags was also a problem.
As long as prescribed methods were used for the clean bench, the air cleanliness inside the clean bench was kept sufficient even through the external air conditions or locations were not so clean.
