High-efficiency ductless fume hoods utilize redundant HEPA filters to capture and remove particles produced during nonsterile hazardous drug compounding. This containment ventilated enclosure provides operator and environmental protection from particles, aerosols, and gases from HDs. The system’s powerful fan pulls powders and particles into the filtration system and releases filtered air into the surrounding room. The redundant HEPA filters meet requirements for a USP 800 compliant containment primary engineering control for nonsterile HD preparations.