Gentek 3940221 User Manual

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Chapter 4: High Performance Features and Safety

Figure 4-2

HEPA Filtered Enclosure Airflow Diagram


Chapter 4: High Performance Features and Safety

1.Aerodynamic Clean-Sweep™Air Foilhas a unique shape that allows air to sweep the work surface for maximum containment. The Clean-Sweep™ openings create a constant protective barrier from contaminants. Should the operator inadvertently block the airflow entering the air foil, air continues to pass under the air foil and through the Clean-Sweep openings. See Figures 4-1 and 4-3.

Figure 4-3

2.Containment-EnhancingUpper Sash Foilincludes an open air passage directly atop the sash foil to bleed air into the hood chamber and direct chemical, powder and particulate materials away from the sash opening. The radiused sash foil sweeps airflow into the hood with minimal turbulence. See Figures 4-1 and 4-4.

Figure 4-4


Chapter 4: High Performance Features and Safety

3.Upper Dilution Air Supply provides bypass air from above the work area. This feature constantly bathes the inside of the sash with clean air and reduces powders, particulate materials and chemical fumes along the sash plane, near the critical breathing zone. Five to seven percent of the required air volume is introduced through the upper dilution air supply. The upper dilution air supply also reduces stagnant pockets of air in the upper interior. See Figure4-2.

4.Zoned Rear Perforated Baffle directs horizontal laminar air streams to thethree-zonedsections of the perforated baffle. Thethree-zonedsections have increasingly more open area at the bottom that help form laminar airflow. This minimizes the potential for air to roll forward preventing contaminants from moving toward the sash opening. The majority of contaminants are highly diluted, captured and removed on the first pass through the enclosure. See Figures4-1and4-2.

5.Side-Entry Air Foils allowturbulence-freeair to enter the enclosure from the sides and allow clean air to sweep the interior walls of the enclosure. See Figures4-1and4-2.

6.Ergonomic Slope of 10 degrees provides maximum visibility, and comfort reduces glare, thereby minimizing operator fatigue. See Figure4-1.

7.Internal Depth of 23" provides necessary depth to support modern balances and other auxiliary equipment without extending outside the enclosure or resting on the lower air foil. See Figure4-1

8.Safety Glass Sash with Spring-LoadedLatchhas a wiping seal to contain contaminants and features a springloaded latch to secure sash open for loading and cleaning. The sash must be down for normal operation. See Figure 4-1.

9.Utility Ports with Iris allows electrical cords and data cords to pass through the back of enclosure without leaving a large hole for contaminants to escape. The enclosure ships with solid plugs. Iris plugs are included with the User’s Manual. See Figure4-1and4-2.

10.Accessory Guardian Airflow Monitor or Guardian™ 1000 Digital Airflow Monitor continuously monitors airflow. An audio/visual alarm alerts the user to low airflow conditions. The Guardian 1000 Digital Airflow


Chapter 4: High Performance Features and Safety

Monitor also displays a face velocity value, provides an RS232 output, a night setback mode and several auxiliary relay ports. Both airflow monitors are available options on all XPert models. See Figure 4-1and4-2.

11.Inherently Safe Impeller has a negative pressure plenum that surrounds the positive pressure impeller so that if a leak should occur, the unfiltered air is captured and refiltered. See Figure4-2.

12.Vibration-IsolatedMotorized Impellerhas vibration isolation supports, which eliminates transfer of vibration to the work surface. This is extremely useful in weighing operations with precision balances. The impeller wheel is also dynamically balanced. See Figure 4-2.

13.Speed Control regulates the speed of the motorized impeller and is used by the certifier to validate and adjust the inflow velocity. Located behind the front panel. See Figure4-2.

14.Space-Saving Design increases effective laboratory workspace, because the impeller and HEPA filter are contained within the enclosure, a separate filtered blower module is not required. See Figure4-1

15.Fluorescent Lamp is located above the work area, out of contact with contaminated air. A safety glass window beneath the lamp distributes the light evenly across the work surface. See Figure4-1.

16.Filter System Pressure Gauge indicates the total system pressure across the HEPA filter and pressurized plenum to help predict HEPA filter loading. See Figure 4-1.

17.Filter Clamping Bolt evenly seals the HEPA filter to the frame of the enclosure. See Figure4-1and4-2.

18.Sash. The sash is constructed of 1/4 inch tempered safety glass. It pivots up for loading and cleaning. See Figure4-1

19.Control Panel. The control panel, which is located above the sash, contains the filter system pressure gauge, control switches and the electronics. See Figure4-1.


Chapter 4: High Performance Features and Safety

20.HEPA (High Efficiency Particulate Air) Filter is rated to remove 99.99% of all particles 0.3 micron in size. See Figure 4-2.

21.Lamp Ballast (Not Shown) for the fluorescent lamp is located behind the control panel.

22.Accessory Work Surface (not shown) is dished and contoured to fit the dimensions of the enclosures to contain spills.

23.XPert Filtered Balance Station Exhaust Collar (Not shown) provides a 6" diameter transition to a remote blower or house exhaust system. See figure 3-2 in Chapter 3.

24.Accessory Odor Control Carbon Filters are available for nuisance odor control. Accessory carbon filters are designed to remove trace amounts of noxious fumes; capacity is not adequate to remove continuous fume generation. The carbon filters are supported above the HEPA filter and the gasket side is down and compressed by the weight of the carbon filter. Carbon filters are listed in Chapter 7. See Figure 4-2.

25.Accessory Exhaust Connection Kits are available to duct integral blower models including the XPert Filtered Balance System to the outside. The exhaust connection allows the operator additional protection from hazardous fumes or vapors and should be used if the carbon filter capacity is not adequate. Each kit includes an epoxycoated steel exhaust transition adapter with manual adjustable damper designed for 6" diameter PVC duct. See Figure 3-3 in Chapter 3.

26.Upper Diffuser Screen provides protection for the HEPA Filter and (LED) airflow sensor. See Figure4-1and4-2.

27.HEPA Filter Access Port to access HEPA filter during filter changing procedures. For harmful powders and particulates, the truebag-in/bag-outprocedure is used to properly dispose of the contaminated HEPA filter. See Figure4-2.

28.Utility Shelves (not shown) allow the user to hold utensils and printers on shelves inside the enclosure. See Chapter 7.


Chapter 4: High Performance Features and Safety

Safety Precautions

1.Although the enclosure has been engineered to maintain optimum operator safety, caution should always be used while working. Prior to using the enclosure, check to make sure that the exhaust blower is operating and that air is entering the enclosure at its specified face velocity. The use of an airflow monitor is recommended to alert the user to a problem with airflow.

2.Use good housekeeping in the enclosure at all times. Clean up spills immediately. Periodically clean enclosure interior.

3.Do not overload the work surface with apparatus or work material. The safe operation of the enclosure is based upon having proper airflow through the structure. Do not place large objects directly on the work surface. Instead, elevate the object 3/4" on blocks to allow a flow of air under the object and into the rear baffle exhaust slots. Ensure blocks are level and secured in place.

4.Blocking large portions of the rear baffle will change the airflow pattern in the enclosure causing turbulence. (Do not store containers or supplies against the rear baffle, as this will affect airflow).

5.Always work with your hands as far back into the enclosure as possible. Keep all powders, chemicals and apparatus inside the lower air foil of the enclosure.

6.Do not work in this enclosure without the exhaust system running.

7.Perchloric acid use in this enclosure is prohibited.

8.High-levelradioisotope materials are prohibited in this enclosure. Consult your Safety Officer.

9.Avoid cross drafts and limit traffic in front of the enclosure. Air disturbances created may draw contaminants out of the enclosure.

10.A qualified certification technician should test the enclosure before it is initially used. The enclosure should be validated whenever it is relocated.

11.The use of safety goggles, protective clothing, gloves and any other personal protective equipment recommended by your safety officer should be used.


Chapter 4: High Performance Features and Safety

12.The sash must remain in the down position while using the enclosure.

13.Proper performance of the enclosure depends largely upon its location and the operator’s work habits. Consult the references in Appendix D.

14.The enclosure should be recertified whenever it is serviced or at least annually thereafter.

15.The HEPA filter provides personnel and environmental protection from particulate matter. Because room air is drawn over the work surface during operation, this enclosure should not be used for operations requiring product protection from environmental contamination.

16.Avoid the use of flammable gases or solvents in the enclosure if possible. Care must be taken to ensure against the concentration of flammable or explosive gases or vapors. Use of an open flame should be avoided in the enclosure. Open flames may disrupt the airflow patterns in the cabinet, burn the HEPA filter and damage the filter’s adhesive. Gases under high pressure should not be used in the enclosure as they may disrupt the airflow patterns of the cabinet.

17.HEPA filters are only effective for entrapment of particulate matter. Manipulations that generate gases or vapors from toxic chemicals or radionuclides, must be evaluated carefully from the standpoint of buildup to dangerous levels, the decontamination of the enclosure and compliance with applicable regulations.

18.The surface of the HEPA filter is fragile and should not be touched. Care must be taken to avoid puncturing the HEPA filter during installation or normal operation. If you suspect that a HEPA filter has been damaged DO NOT use the enclosure; contact a local certification agency or Labconco.

19.The HEPA filter in the enclosure will gradually accumulate airborne particulate matter from the room and from work performed in the enclosure. The rate of accumulation will depend upon the cleanliness of the room air, the amount of time the enclosure is operating and the nature of work being done in the enclosure. With normal usage, the HEPA filters will last two to five years before requiring replacement.


Chapter 4: High Performance Features and Safety

20.Ensure that the filtered enclosure is connected to an electrical service in accordance with local and national electrical codes. Failure to do so may create a fire or electrical hazard. Do not remove or service any electrical components without first disconnecting the filtered enclosure from electrical service.

21.Use of an open flame must be avoided with the enclosure. Open flames may disrupt the airflow patterns in the enclosure and cause a fire hazard with volatile solvents.

22.Increase the face velocity by adjusting the speed control of the motorized impeller on the XPert Filtered Balance System or change the HEPA filter when the face velocity falls below acceptable limits established by your Safety Officer.

23.Exhaust carbon filters and HEPA filters are disposed as hazardous waste. The user is responsible for recording the chemicals adsorbed or treated by the filters and disposing properly. HEPA filters should be disposed using the disposal bag on XPert enclosures.

24.Ensure only trained operators use the enclosure. New users should review the User’s Manual and become familiar with the operation of the enclosure.

25.If the filtered enclosure is to be used in a confined space, make sure the space is well ventilated and the concentration of toxic contaminants cannot accumulate greater than the TWA.

26.Proper operation of the enclosure depends largely upon the enclosure location and the operator’s work habits. The enclosure should be located away from traffic patterns, doors, fans, ventilation registers, fume hoods, and any other air-handlingdevice that could disrupt its airflow patterns. ConsultChapter 2: Prerequisites andChapter 3: Getting Started sections of this manual for further details.

27.Only powders and particulates removed by HEPA filters and trace chemicals, which can be safely adsorbed and treated with specific carbon based filters are appropriate for use in this enclosure.

28.The warning properties (i.e., odor, taste) of the volatile organic compounds or other material being used in the enclosure must be adequate to provide an early indication that the carbon filter may be saturated or inadequate. Contact Labconco for help with chemical assessment.


Chapter 4: High Performance Features and Safety

29.Use the smallest possible quantity of chemical(s) within the enclosure and never exceed the amount, which can be effectively adsorbed by the Odor Control carbon filter before breakthrough.

30.For weighing procedures, adjust face velocity between 60 and 100 FPM for effective operation.

31.Leave the blower on for at least one minute after work in the enclosure has been completed.

32.If a chemical, powder or particulates are spilled on the work surface, DO NOT switch off the blower until all traces have been removed.

33.Tag enclosures with appropriate warning, if filters have been removed for service.

34.If the blower fails during use, processes should cease and the area should be vacated and ventilated.

35.Always refer to the NIOSH Pocket Guide to Chemical Hazards before proceeding.






Now that the installation of your filtered enclosure is completed, you are ready to use your filtered enclosure. Read this chapter to learn about:

1.Routine Daily Work Procedures.

2.Suitable Applications.

3.Appropriate HEPA Filter Applications, Suitability and Guidelines.

4.Odor Control Carbon Filter Applications.

5.Definition of Terms.

6.Appropriate Chemicals for Odor Control Carbon Filters.

7.Hazardous Misapplications for Odor Control Carbon Filters.

8.Chemical Carcinogen use with Odor Control Carbon Filters.

9.Prohibited Acid Use.

Routine Daily Work Procedures


Thoroughly understand procedures and equipment required before beginning work.