Esco Class II, User And Service Manual

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Class II Biological Safety Cabinets
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Perform surface decontamination on the surfaces of any materials, containers or apparatus with
appropriate disinfectant before entering or exiting the work area.
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Place the waste container (biohazard bag, pipette discard pans, etc.) inside the BSC work area.
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Place all items and apparatus in the safe working area.
Figure 3.2. Safe Working Area
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Minimize room activities (personnel movements, closing and opening of doors, etc.) since these
external airflow disturbances may adversely affect the BSC’s internal airflow, thereby possibly
impairing the containment capabilities of the BSC.
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Ensure that the sash is at normal operating height (READY state) before starting any experiment.
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Ensure the front and back air grilles are not obstructed by your arms or any other objects.
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Work as far back in the BSC as possible - at least 150 mm (6 inches) behind the front air intake grille.
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Wait for around one minute after placing the hands into the cabinet prior to any manipulation.
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While working in the BSC, move your hands slowly and in a controlled manner. Rapid movements may
disrupt the air barrier, allowing contaminants to escape or enter the BSC.
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The use of bunsen burner inside the work zone is not recommended. However, if the use of bunsen
burner is unavoidable, a burner that is capable of being used on demand or an enclosed electric micro
incinerator may be used but they must be placed towards the back of the work surface in the BSC.
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Place aerosol-generating instruments as far back in the BSC as possible and at least 150 mm (6 inches)
from clean items/materials.
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Place air turbulence generating equipment such as centrifuges, blenders or sonicators towards the
back of the BSC. Stop other work while any of these equipment is in operation.
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As much as possible, it is recommended that the BSC be operated continuously in order to achieve
optimal containment and cleanliness. Airflow studies have shown that once the fan has been
switched off, air from the BSC may escape due to the thermal currents from inside the BSC.
Therefore, it is recommended that post purge time is set to clear the work zone of contaminants after
work in the BSC is completed. Air balance is an important consideration when determining the
operation mode of the BSC since the air discharged through ducted BSC must be considered in the
overall air balance of the laboratory.
3.4. Working Ergonomics
On most occasions, you would most likely be operating the BSC in a sitting rather than a standing position.
There are some obvious advantages of the sitting position:
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The physiological energy cost and fatigue involved in sitting are relatively less.
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Sitting position provides the body with a stable support.
However, sitting position has some drawbacks too:
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The working area available is fairly limited.
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There is a potential risk of being constrained in the same posture for a long time.
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Sitting position is one of the most stressful postures for one’s back.
Therefore, you should pay careful attention to the following guidelines in order to achieve comfortable and
healthy working conditions: