The PharmaGard NTE797 creates a negative pressure clean air [ISO Class 5] total exhaust controlled environment for the aseptic compounding of hazardous drugs. The HEPA filtered work area maintains a negative air pressure relative to the interchange compartment, which operates at a negative air pressure relative to the surrounding room. These levels of protection minimize the possibility of chemotherapy agents or other hazardous materials migrating from the work area into the surrounding room as well as minimizing the possibility of contamination migrating into the work zone.