Call Find an International or Domestic Terra RepresentativeFor the best experience on our site, be sure to turn on Javascript in your browser.Copyright 1999 - 2020 Terra Universal. We have a complete range of Desiccator cabintes, Glove boxes, Vertical Laminar Flow hoods, Horizontal Laminar Flow Hoods, Cleanroom Laminar Flow Storage Cabinets, Laboratory Exhaust Fume Hoods etc. There are compelling reasons to choose either airflow system, depending on clearance requirements, process location, work surface design, and operator safety.Room air (in red) enters the system from above the HEPA filter; 99.99% particle-free air is forced downward toward the work surface.Vertical laminar flow hoods are often chosen because they resemble, on a small scale, the design of a laminar flow cleanroom, in which fan/filter units are typically positioned in the ceiling.

Horizontal Laminar Flow Diagram Although both airflow designs provide effective sweeping action near the filter face, their respective flow patterns eventually encounter disruptions that often tip the scale in favour of one or the other configuration. These clearance requirements necessitate a deeper bench and more floor space than a vertical flow system.Although both airflow designs provide effective sweeping action near the filter face, their respective flow patterns eventually encounter disruptions that often tip the scale in favor of one or the other configuration.

These fans are rated based on the volume of air that they produce at zero static pressure in cubic feet per minute (CFM). As long as hands and other contamination sources move up and down, not sideways above a sample, sensitive materials will remain clean.Finally, consider the effects on operators of air exiting the laminar flow hood. A laminar airflow cabinet is a working station that comes with Prefilters and HEPA Filters/ULPA Filters. A deeper workbench and floor space will be required due to fan and filter placement.When working with smaller particle applications such as the pharmaceutical industry a vertical flow hood may be desired. Company Registration No. This design ensures that the cleanest (and most germ-free) area will always be the upstream area closest to the filter face.

Clean benches do not offer personnel protection. Laminar Flow hood-Vertical Airflow Diagram. A perforated or rod-top work surface allows the laminar air stream to pass through the hood with minimal obstruction, but these tops can be a problem in operations involving liquids or small parts. They do not protect the operator as the airflow pushes aerosols or particulates from the work surface toward the operator.Where biological safety is required, the Purair BIO offers a Class II, Type A2 NSF certification for personnel, work surface and environmental protection from airborne particulates and biologicals. A vertical flow hood will move air from the top of the unit through filters and down to the work surface.Things to consider before purchasing a flow hood is the direction the air should flow, operator safety, clearance requirements, work surface required.Fans and filters are positioned at the top of a vertical configuration hood. If you’re working with these materials and want to avoid picking up parts off the floor, a horizontal flow design may be preferable.Yet even a solid top may not rule out vertical flow if work is performed above the work surface. Laminar flow hoods are designed to protect samples and parts from particulate contamination. Room air (in red) enters the system from behind the HEPA filter; 99.99% particle-free air is forced in a back-to-front direction across the work surface. By directing the laminar flow downward, vertical laminar flow reinforces the effect of gravity and sweeps particles out of the enclosure, generally through a front access area. Air is drawn through a HEPA filter and blown in a very smooth, laminar flow towards the user. The module may be used as an independent unit or may be combined with the EVL enclosure to form a Class 100, Federal Standard 2090 horizontal … Work is generally done in that clean zone, as far as possible from obstructions that create turbulence.Vertical laminar flow cabinets are often chosen because they resemble, on a small scale, the design of a cleanroom, in which fan/filter units are typically positioned in the ceiling. If sterile or particle-sensitive processes are performed in a clean, sterile zone midway between the work surface and the filter face, a vertical flow cabinet is generally acceptable. Since the fan and filters sit at the top of the unit the flow hood can be installed on a standard lab bench.

Due to the direction of air flow, the sample is protected from the user but the user is not protected from the sample. The air flows down to the work surface in a laminar flow pattern where it splits and re-enters the plenum, Here, 70% of the air is recirculated and 30% is passed through another HEPA filter to be exhausted to the room.For assistance in choosing the right product for your application, ©2020 Air Science® USA LLC. Begin at the back of the unit and work your way to the front; In a vertical-flow cabinet, the obvious obstacle is the work surface. Laminar airflow is defined as air moving at the same speed and in the same direction, with no or minimal cross-over of air streams (or “lamina”).

A perforated work surface allows the laminar air stream to pass through the cabinet with minimal obstruction, but these tops can be a problem in operations involving liquids or small parts. Start by cleaning the laminar flow hood ceiling; Clean the side walls, use a sweeping motion from left to right moving from top to bottom; And lastly, clean the work surface.