A laminar air flow workstation is a sealed cabinet equipped with HEPA filtered air flow system. The air flow velocity ranges between 0.3 m/s to 0.5 m/s. The primary purpose of using such workstation in laboratory is to set up particle and bacteria free working environment in order to execute specialized work. As these units release air towards user, they bestow no peculiar protection but product protection from impurities present in the room. Laminar flow hoods render a filtered airflow across the work area that safeguards the sample from airborne contamination. Laminar flow hoods are perfect for a variety of applications and especially where pureair and sterile environment is compulsory, for instance numerous medical and research laboratories, assembly workplace of sterile equipment or electronic devices.
Functions of Laminar air flow:
Laminar air flow systems are used in variant applications such as life science research, microbiology, IVF, IUI, pathology lab, plant tissue and cell culture and pharmaceutical and electronics industry and much more.
There are two different types of laminar air flow cabinets- horizontal and vertical. The dissimilarity between vertical and horizontal laminar flow hood is direction of air flow and installation of HEPA filter. These cabinets are made with either horizontal or vertical air flow systems and have two stages filtration. It is the type of application, which is perfect to use.
Uses of vertical and horizontal laminar flow hood are mentioned below-
- Vertical laminar flow hood-
Vertical laminar flow hoods are perfect for operations that demand the use of large equipment on the work surface as the workspace is taller and larger with less turbulence caused by the vertical airflow. Vertical laminar flow hoods are often preferred for multiple applications due to their similarity with cleanroom setups. So it is the most used type of laminar air flow.
In this type of cabinet, room air is allowed to enter in working area through HEPA filter fitted on top of the cabinet. So in vertical flow hoods, clean filtered air progresses in downward direction from the filter surface on the top to the work surface and leaves the cabinet wiping out particles and bacteria.
- Horizontal laminar flow hood-
In horizontal air flow cabinet, room air is entered in working area through HEPA filter equipped on the back portion of the cabinet. In this type of cabinets pure air progresses from a fliter located behind the work surface towards the operator. Filtered air thus flows horizontally towards the user creating clean working ambience.
Additionally, a horizontal laminar flow hood comprises of a filter pad, a fan and a HEPA filter too. The fan extracts the air through the filter pad where dust is trapped. After that the filtered air has to pass through the HEPA filter where harmful fungi, bacteria and dust particles are eradicated. In fact, horizontal laminar flow hood have a taller and a larger working area which support the internal placement of instruments like microscopes.
So air flow direction depends on the type of procedure, operator security, and clearance exigencies too.