A laminar flow cabinet or tissue culture hood is a carefully enclosed bench designed to prevent contamination of biological samples, semiconductor wafers, or any particle sensitive materials. In a biosafety cabinet version air is drawn through a HEPA filter and blown in a very smooth laminar flow in a narrow vertical curtain, separating the interior of the cabinet from the environment around it. The cabinet is usually made of stainless steel with no gaps or joints where spores might collect.[1]