Cleanroom Solutions

Laminar Flow Cabinets

What is a laminar flow cabinet?

A laminar flow cabinet, also known as a laminar flow unit or laminar flow hood, uses laminar airflow to remove contaminating particles from an enclosed space with a primary function of providing a controlled, clean environment for handling materials, samples, or products that are sensitive to contamination. It is a crucial piece of equipment utilised in various industries, including pharmaceuticals, microbiology, electronics, and food processing.


Laminar Flow Cabinet NHS

How does a laminar flow cabinet work?

The laminar flow cabinet works by directing filtered air either vertically or horizontally in a uniform, laminar (parallel) flow over the work surface. This airflow creates a barrier that prevents airborne particles, dust, and microbes from entering the workspace, thereby maintaining a clean environment suitable for tasks requiring a high degree of cleanliness.

Vertical Laminar Flow Cabinet

A vertical laminar flow cabinet is designed with a vertical airflow pattern, where the air is filtered through a HEPA or ULPA filter and drawn from the top of the cabinet, flowing vertically down onto the work surface. This configuration is ideal for applications that involve working with delicate samples or equipment, such as cell culture work, PCR preparation, or electronics assembly.


  • Easy access for filter changes and servicing
  • Reduced cross-contamination of items on the work surface due to the absence of parallel airflow
  • Can accommodate tall and large products and materials due to the taller design


  • May require overhead clearance for filter changes and servicing
  • Increased turbulence on the work surface due to vertical air hitting perpendicular surfaces
  • The presence of stacked products and materials can obstruct airflow

Vertical laminar flow hoods are popular due to their compact size, layout, and enhanced operator safety. With the filter at the top of the unit, they require less floor space but can be taller to accommodate larger products and materials. Additionally, as the laminar air is not blowing towards the operator, the risk of contaminants reaching sensitive materials is reduced.


Horizontal Laminar Flow Cabinet

Vertical Laminar Flow Cabinet

In contrast, a horizontal laminar flow cabinet features a horizontal airflow pattern, where the HEPA/ULPA filtered air is blown parallel to the work surface from the back of the cabinet towards the user. This setup is commonly used in industries where larger equipment or materials need to be processed, such as in microbiology labs or pharmaceutical production facilities.


  • Low turbulence on the work surface due to parallel airflow
  • Easy positioning of products and materials close to the filter on the work surface
  • Minimal contamination from hands or gloves as the operator remains downstream from the products and materials


  • Requires hood repositioning for rear access during filter changes and servicing
  • Objects can obstruct the airflow and contaminate downstream materials
  • Improper use of the sash can lead to fume or powder contaminants blowing at the operator

Horizontal laminar flow hoods provide the highest protection against contaminating particles by sweeping the air across the work surface towards the operator. This design eliminates the turbulence caused by vertical air striking perpendicular surfaces or the operator’s hands, as they are always downstream from the materials they are working on.


How to choose the right laminar flow cabinet

Both horizontal and vertical laminar flow cabinets effectively reduce contamination in workspaces involving sensitive products and materials. However, certain applications are better suited to one configuration over the other. Factors such as process location, clearance requirements, material size, work surface design, and operator safety are crucial in determining the ideal choice.

Vertical laminar flow hoods are also an excellent choice for large or potentially hazardous materials applications. Whereas horizontal laminar flow cabinets are generally recommended for applications requiring minimal work surface turbulence and a high level of object contamination control.

For more information and advice regarding laminar flow cabinets, contact us today and a member of our team will be happy to assist you.


If your cleanroom requires laminar flow hoods, our team can provide expert advice so you can select the option that seamlessly meets your classification and industry requirements. You can choose from our standard sizes or speak to us about bespoke requirements.