Baker SterilGARD SG303 Operator's Manual

Contents

Baker SterilGARD SG303 Operator's Manual Manual pdf 6 page image

4Positive and Negative Pressure AreasOne of the many features that sets the SterilGARDIII Advance apart from other biosafety cabinets is theinteraction of positive and negative pressure areas. The small positive pressure plenum is completelysurrounded by a negative pressure area so that any particle passing through is bound to be drawn through theblower and trapped in a HEPA filter.From the small positive pressure plenum, which is shown in Figure 1, a portion of the cabinet airflow isexpelled through the exhaust HEPA filter. The remaining air is re-circulated through the supply HEPA filterwhere it re-enters the work area at better than Class 10 air. Because the cabinet must take in air to replacethe air expelled through the exhaust filter, the same volume of room air enters the cabinet through the frontaccess opening and the high velocity return air slots. This air, which does not reach the work area untilpassing through the supply HEPA filter, completes the air barrier at the front access opening.All air is combined under the work surface. From here, the contaminated air is pulled, under negativepressure, through a plenum up the rear of the cabinet into the motor-blower, which blows it into a positivepressure plenum. Please note again that the positive pressure plenum is completely surrounded by negativepressure areas. If a leak should occur in a contaminated negative pressure plenum, such as the side wall orrear wall, the negative pressure will create suction and pull air in, not allowing it to escape into the operator'sarea. If there is a leak from the positive pressure plenum, the surrounding negative pressure area willrecapture the contaminated air and re-circulate it through a HEPA filter.Access to the Work AreaFor easy entry of apparatus into the work area, SterilGARDIII Advance has a sliding viewscreen. Its ¼”safety plate glass allows excellent visibility and may be opened to a height of 18-1/4” to permit placement ofitems in the work area. The window should be set at a height of 8”. An alarm is provided to remind theoperator if the window is above the maximum position for using the cabinet (see Section III, ProperCabinet Use for how to use the viewscreen correctly while the cabinet is in use).As with other Baker cabinets, the GFCI protected electrical outlets inside the work area are protected by aseparate circuit breaker so that an electrical overload by ancillary equipment won’t affect air handling.Overloading with electrical equipment should, of course, be avoided in any case (see “Using AncillaryEquipment” in Section III, Proper Cabinet Use).Design DetailsPerformance assuranceMeticulous care in manufacturing is followed by more than 14 separate performance tests prior toshipment of this cabinet. In addition, a complete factory test report on the performance of this cabinet isincluded with this manual.Ergonomic enhancementsThe Baker Company has also included ergonomic enhancements into the design of the SterilGARDIIIAdvance for improved operator comfort and safety. A 10-degree sloped front feature has been