Frequently Asked Questions

• Ensure main power supply has been removed prior to any work being carried out.
• To replace a light bulb, access panel located on rear of hood.
• Remove 6 screws to release the panel.
• Rotate bulb ¼ turn counter clockwise to remove and replace.

• Class I Biological safety cabinets are designed solely for operator protection.
• Class II and Class III protect the product or specimen, the user and the environment from contamination.
• Class II cabinets have open access to the work zone while Class III BSCs, often referred to as glove boxes, provides a barrier between the user and the work area.
• A class III biosafety cabinet is crucial for working with any biosafety level 4 agents or other dangerous materials, such as aerosols of pathogens or toxins.

• Your application utilizes large equipment on the work surface, as vertical flow creates less turbulence when encountering large items within the airflow.
• Your application requires that soldering fumes or fine powders be used, as greater operator protection is provided.
• You need a taller, larger work space, as filters are generally positioned on top, providing greater height for the work surface.

1. Adjust the seating position so that the user's face is above the front opening. Adjustable stool is recommended.
2. Turn on the fan. Leave the cabinet on for 5 minutes before beginning work in order to purge airborne con­tamination from the work area.
3. Prepare a written checklist of materials/apparatus necessary for immediate usage and surface-decontaminate before loading them into the work zone. This is to prevent overloading and to minimize the number of arm movements that might disrupt the airflow.
   • Never use the cabinet to store supplies or laboratory equipment.
   • Keep the rear air grilles unobstructed by arms or objects.
   • Always surface-decontaminate all items before inserting into the work zone.
4. Load and arrange the materials/apparatus to minimize the movement of contaminated items over clean items by segregating the contaminated items from the clean items.
5. A clean, long-sleeved laboratory coat may be used to protect personal clothing.
6. Wash hands thoroughly using germicidal soap. Wear gloves for hand protection. Gloves should be pulled over the knitted wrists of the gown rather than worn inside.
7. Minimize room activity (personnel movements, closing and opening doors, etc.).
8. Thoroughly surface decontaminate the work surface, inner back walls and interior surface of the window using 70% ethanol or other disinfectant depending on the requirements of the user.

1. Work from clean to dirty by following the segregation of clean and dirty materials/apparatus as described in the Start-Up Procedure above.
2. Particularly critical objects may be arranged such that air flows directly against them while the rear air grilles remain unobstructed by arms or objects.
3. Do not use a gas flame, if possible, as it interferes with airflow.
4. Do not use writing materials inside the work area as they generate aerosols.
5. Do not change the original blower speed of the cabinet unless the change is required by a decrease in measured air velocity. Adjustment should be made only by a qualified technician.
6. Do not operate the cabinet if fan fails to run.
7. Do not cough or sneeze into the work zone.
8. Minimize arm movement. Move arms in and out of the cabinet slowly to avoid disrupting cabinet airflow. Surface decontaminate prior to inserting arms into the cabinet.
9. Use absorbent pads on the work surface where appropriate to minimize splatter and aerosol generation in case of spillage.
10. Clean materials should be at least 150 mm away from aerosol generating objects to minimize the chance for cross contamination.
11. Hold lids/covers above dishes/sample plates in order to prevent air impingement where appropriate.
12. Arrange objects to avoid airflow turbulence.
13. Keep arms as far away as possible from items in the work zone.
14. Keep heads (large potential for aerosol generation) out of the work zone.
15. It is recommended that the cabinet be operated continuously whenever possible to ensure cleanliness.

• Run the cabinet for at least 15 to 20 minutes prior to cleaning.
• Wear sterile clothing and cleanroom gloves.
• Always use lint-free cleanroom cloths.
• Use a different cloth (or alternate surfaces of a folded cloth) for each different wall or surface of the unit.
• Use 70% isopropyl alcohol for a cleaning solution.
• Always clean from back to front, top to bottom.
• Beginning in a top back corner, wipe down the entire span of wall surface with long, side-to-side motion.
• Overlap each swipe by at least 25% coverage.
• Do not attempt to clean the HEPA filter. Doing so could damage the media.
• When cleaning a vertical laminar flow hood, the back wall should be cleaned. (The filter is located above the unit.)

Remember to clean your laminar flow hood in the following order:

• Clean the ceiling of the unit first.
• For a vertical laminar flow hood, clean the back wall next, from top to bottom.
• Clean the sides, swiping from top to bottom in overlapping lines.
• The work surface should be the last surface cleaned, beginning in the back and ending at the front of the unit.

• Consult your safety officer or industrial hygienist before removing or disposing of any filters.
• Filters should be replaced at least annually, or if the airflow alarm is illuminated.
• Hazards associated with the removal and disposal of used filters will depend on the application of the hood.
• Ensure persons removing filters are made aware of any potential hazards and that they are
• provided with any necessary protective clothing and equipment.
• If an activated carbon filter is used with hydrocarbon solvents, the filter will retain the solvents without loss, and can be removed in the laboratory. The used filter should be sealed into a plastic bag prior to disposal, preferably by incineration.
• If the filter has contained any dangerous materials such as asbestos dust or radioactive chemicals, operator protection is advised, including the use of a respirator. The used filters may require disposal by a specialist company.
• Disconnect the power supply before removing filter access cover.

Pre-Filter

• The pre-filter is located below the main filter. Remove the perforated pre-filter tray. Remove the old pre-filter and place it into a bag. Seal for disposal. Refit the new filter and refit the pre-filter tray.

Main Carbon / HEPA Filter

• All filters are accessible from the front. No tools are required for removal and replacement, although filter doors are keyed to prevent unauthorized access.
• Remove the front cover to gain access to the filter. Loosen the filter clamps. Lift the filter slightly to break the seal and then withdraw the filter. Place the filter in a plastic bag. Seal the bag for disposal.
• Slide the new filter into position by pushing the filter fully into the module. Refit the front cover and lock it in position.
• A filter identification window shows the installed filter part number and installation date to simplify ordering and replacement scheduling.

• The low airflow alarm operates using a differential pressure switch to detect a “high vacuum” situation when the pre-filter is blocked or is blocking up. The pressure switch is calibrated and tested prior to leaving our factory and under normal circumstances will not require any adjustment.
• With the cabinet running and the pre-filter blocked as described above, locate the grey pressure switch through the hole in the right-hand sidewall. Adjustment is made by turning the small screw in the end of the switch.
• Adjust the screw to make the alarm show. You may have to repeat these steps to ensure an accurate setting has been achieved.
• Remove the blockage and restart the machine. The red/amber neon should not be illuminated.