Laminar Flow Hoods come in Vertical Laminar Flow (VLF) cabinets and Horizontal Laminar Flow (HLF) cabinets. They are designed to protect items in the work zone from particulate contamination using laminar airflow. Laminar flow is best described as airflow in which the entire body of air within a designated space is uniform in both velocity and direction. In other words, the airflow close to the solid surface is moving in straight lines parallel to that surface.
Laminar flow hoods are designed to deliver airflow that is uniform in both velocity and direction that sweeps particulates out of the enclosure. However, it is impossible to have true laminar flow within a ducted or ductless hood. The necessity of equipment and products on the work surface, in addition to arms/hands inside the hood, inevitably disrupt laminar airflow and create unintentional swirls within the workspace. These swirls can lead to contamination. High quality laminar flow hoods minimize turbulence from items inside the enclosure.
Keeping Laminar Flow Hoods Contamination Free
Air Science® laminar flow hoods go a step further by using an advanced filtration system to ensure laminar flow hoods are contamination-free. At the core of our laminar flow hoods and cabinets is the Air Science Multiplex™ ULPA filtration technology that creates a clean work environment over a wide range of applications.
The Air Science Multiplex Filtration System consists of a pre-filter and main filter to create a combination of chemical and physical architecture customized to each application. For example, in Purair® FLOW and Purair PCR hoods, the Multiplex System includes a disposable polyester fiber pre-filter with 85% arrestance, a main HEPA filter with 99.99% efficiency for 0.3-micron particulates and an optional ULPA safety filter with >99.999% typical efficiency for 0.12-micron particulates. Purair LF Laminar Flow hoods, however, use Multiplex ULPA Filtration Technology which features an ULPA main filter.
In short, the Multiplex option permits one or more filtration options to be combined to meet a wider range of particulate-capture needs. This helps ensure a contaminate-free environment for work sensitive to particulates.