In Formas Class II, Type A/B3 cabinets, the airflow descends from the top of the cabinet through a supply HEPA filter. As this vertical airstream approaches the work surface the airflow splits with approximately 50% being drawn into the cabinets rear intake grille and the rest meeting ambient room air at the front intake grille. The air is then drawn into a plenum surrounding the work area by the blower located in the top of the cabinet. The blower pressurizes this air into a positive pressure plenum. The pressurized air is split, with 30% being exhausted through the exhaust HEPA filter and the remaining 70% recirculated through the supply HEPA filter.
The air being drawn into the side, back and front grilles, combined with the laminar HEPA filtered downflow air, provides a sterile work area and cross contamination protection.
The area where room air and HEPA filtered air meet, produces an air barrier that provides personnel and product protection.The HEPA filtered exhaust air provides environmental protection.
Class II, Type B3 cabinets may be used with agents assigned to biosafety levels 1, 2, or 3 treated with minute quantities of volatile toxic chemicals and tracer amounts of radionuclides required as an adjunct to microbiological studies that will not interfere with the work when recirculated in the downflow air.
For personnel protection, air is pulled into the 4.0" (10.2cm) wide intake grille. This air meets the uniform, downward, HEPA filtered air and keeps unfiltered air out of the work area. Exceptional product protection is achieved because the directed airflow minimizes the chance of cross contamination along the work surface. High velocity momentum air curtains are not required.
Forma's Vortex Channels (U.S. Patent 5,295,902) create high velocity air at the window corners to inhibit the escape of particulates. The downward, HEPA filtered air behind the viewscreen meets the multi-directional inward flowing air. This multi-directional air at the corners of the window opening can create turbulence, which increases the risk of particulates escaping from or entering the cabinet work area. Our Vortex Channels, located at each end of the intake grille, provide high velocity air that sweeps the turbulent air into the return air system before it reaches the work area. Product and personnel protection are increased.
Reliable, rocker style switches on the control panel are easy to use. Independent service organizations have indicated that customers prefer our control panel design because it is easy to use and inexpensive to replace if service is required. Microprocessor controls used by other manufacturers can cost hundreds of dollars to replace if a problem occurs.
The blower continues to operate when the sliding window is closed. This feature lowers the ambient sound level and saves setup time while keeping the work area purged and ready for immediate use. Other manufacturers blowers automatically shut off when the window is closed.
Return air slots, located just above the work surface on each side wall, provide increased sample cross contamination protection. Forma Scientific is the only manufacturer to offer this additional sample protection.
Dual-wall construction design allows us to surround the entire work area with a negative pressure air plenum. This design feature provides the following benefits: an added measure of safety to the environment; return air slots for enhanced sample cross contamination protection; sturdy, aesthetically appealing units; and the ability to locate all utility plumbing connections inside the wall where they are out of the way and out of sight.
Forma Biological Safety Cabinets feature an all-metal, positive pressure plenum (enclosed within negative pressure air) with a patented hook and loop connection (U.S. Patent 6,036,737) to the exhaust damper. This unique design accommodates quick and easy filter changes for lower maintenance costs. All maintenance functions, including HEPA filter replacement, can be performed from the front of the biological safety cabinet. Positive feedback from certification companies attests to the success of Forma's innovative plenum attachment system.
Forma Type A/B3 Cabinets can handle a 100% increase in filter loading without adjustment and at least a 230% increase in filter loading with voltage and damper adjustments, while still maintaining 90% of the total CFM.
Weight: 450 lbs
Warranty: 30-Day Warranty, 100% Parts and Labor
Includes: Power Cord