Drug preparations must be performed only with the view screen at the recommended access opening. Professionally accepted practices concerning the aseptic preparation of injectable products should be followed. All materials needed to complete the procedure should be placed into the biological safety cabinet before beginning work to avoid interruptions of cabinet airflow. Allow a two to three minute period before beginning work for the unit to purge itself of airborne contaminants. The proper procedures for use in the biological safety cabinet differ from those used in the horizontal laminar hood because of the nature of the airflow pattern.
Clean air descends through the work zone from the top of the cabinet toward the work surface.
As it descends, the air is split, with some leaving through the rear perforation and some leaving through the front perforation. The least efficient area of the cabinet in terms of product and personnel protection is within three inches of the sides near the front opening, and work should not be performed in these areas Entry into and exit from the cabinet should be in a direct manner perpendicular to the face of the cabinet. Rapid movements of the hands in the cabinet and laterally through the protective air barrier should be avoided. Compounding Procedures and Techniques Hands must be washed thoroughly before gloving and after gloves are removed. Care must be taken to avoid puncturing of gloves and possible self-inoculation.