Primary Engineering Controls in Pharmaceutical Compounding, Part 2: Biosafety Cabinets.

Minimizing contamination by airborne particulates is essential in pharmaceutical compounding, and biosafety cabinets have long been among the most effective types of equipment used to achieve that goal. In this article, which is the second of a 2-part series on primary engineering controls, the 3 classes and various types of biosafety cabinets are reviewed. In those units, directed airflow and high-efficiency particulate air filtration sweep airborne contaminants away from the operator, the preparation, and/ or the environment. Factors to consider before operating a Class-2 biosafety cabinet (the unit most often used in compounding) are briefly discussed, information about technician certification and training is reviewed, and diagrams demonstrating the mechanism of operation of several Class-2 units are provided. In part 1 of this series, other types of primary engineering controls used in compounding (unidirectional airflow workstations, compounding aseptic isolators, and compounding aseptic containment isolators) are discussed.