Vertical Laminar Air Flow

A vertical laminar flow cabinet (or clean bench) is a workspace enclosure that directs HEPA-filtered air downward in a uniform, “laminar” stream to create an aseptic work area. It prevents airborne particles from settling on the work surface. Unlike biosafety cabinets (which protect the user), vertical laminar flow hoods protect only the product/samples from contamination. Air enters through the top (or back) HEPA filter and is expelled vertically through the work surface.

Type of Product
Key distinctions in laminar flow units include:

• Vertical vs Horizontal Flow: A vertical flow unit directs air downward from the top (as in question); a horizontal flow hood directs air toward the user from the back. Both use HEPA filters for cleanliness. Vertical flow benches typically have a perforated work surface so filtered air can pass down.
• Enclosure Size: Small bench-top models vs large walk-in enclosures (cleanrooms). Some are benchtop units on stands; others are integrated tables or cabinets.
• Flow Rate and Filter Class: They vary by air velocity (typically ~0.3–0.5 m/s) and HEPA/ULPA filter ratings (e.g. 99.97% at 0.3 µm for ISO Class 5 clean air).
• Features: May include UV sterilization lamps, antimicrobial surfaces, and vibration-free designs. Some built-in hoods have sinks or lighting.

Applications in Various Industries
Vertical laminar flow cabinets are used wherever sterile or particulate-free conditions are needed for the workpiece:

• Pharmaceutical and Medical Labs: Aseptic filling, media preparation, or sample handling (not involving biohazards to user).
• Electronics: Clean assembly or inspection of sensitive components (circuit boards, semiconductors) to avoid dust contamination.
• Biotechnology and Research: Tissue culture work (non-hazardous) where contaminants must be kept out of cell cultures.
• Optics and Precision Parts: Assembly of optical lenses, laser parts or precision instruments.
• Food and Cosmetics: Filling and packaging of sterile products (dry filling of nutritional bars, etc.) where product must remain uncontaminated.
  
  
  

Material Selection Consideration
Surfaces must be cleanroom-compatible:

• Construction Materials: Cabinets are usually made of powder-coated steel or stainless steel for easy cleaning and corrosion resistance. Work surfaces and interiors are often stainless steel (304 or 316) to avoid off-gassing and allow sanitizing.
• Filter Media: HEPA filters are made of borosilicate glass fiber. Filter frames are metal or plastic.
• Windows and Panels: Clear panels (if present) use tempered glass or acrylic for chemical resistance and visibility.
• Seals and Gaskets: Silicone or EPDM rubber seals maintain the airflow integrity. All materials meet cleanroom standards to avoid particle shedding.