Chemical Fume Hood and Biosafety Cabinet

Side-by-side comparison diagrams of a chemical fume hood and a biosafety cabinet.

Left: The chemical fume hood draws room air inward through the front opening, across the work surface and hazardous materials, then exhausts contaminated air through a duct to the outside.

Right: The biosafety cabinet shows room air entering through the front grille, contaminated air circulating inside the cabinet, and HEPA-filtered air moving through internal filters and out the top exhaust. Labels A–D identify airflow and filtration components.