For pharmaceuticals that cannot be given terminal sterilization at the end of production, the alternative of aseptic fill is available, requiring sterile materials placed in sterile containers in a cleanroom. Nonviable particles >10 μm and viable particles must be kept away from the product. Part of contamination control involves wiping the walls, tables, and equipment so as to remove contamination. Another part is disinfection. The cleaning of aseptic fill areas must be done in a systematic manner, described here, and audited for effectiveness. Removal of contaminants aids disinfection and is usually carried out by chemical means, using sterile wiping materials.
Advanced methods of contamination control are essential to successful pharmaceutical manufacturing, especially pharmaceuticals that do not receive terminal sterilization but rather are packaged using aseptic fill techniques in cleanrooms. The rooms typically contain automated equipment and some personnel, filling vials, IV pouches, etc., with measured amounts of a given drug. The strategy is simple: sterilize the containers, sterilize everything that enters the containers, then perform the filling in a virtually sterile environment.
Planning and building such cleanrooms was covered in a recent article by Hansz and Linamen. Useful details and standards concerning various aspects of sterilization are available in the recent book by the Association for the Advancement of Medical Instrumentation, covering ethylene oxide, steam, other chemical sterilants; gamma radiation; and electron beam radiation. Background information on cleanroom microbiology is available in a new book by Carlberg.