The document provides an overview of biological safety cabinets, their purpose in protecting workers, samples, and the environment from infectious materials. It details the design, operational theory, types, installation requirements, maintenance procedures, and functional evaluations needed for safety cabinets. Additionally, it outlines certification tests necessary to ensure proper functioning and safety standards.

1. Biological Safety Cabinet
 This equipment is designed for controlling aerosols
and microparticles associated with toxic or infectious
biological material in laboratories in activities.
 Main purposes of biological safety cabinet,
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To protect the worker from risks associated with the management of
potentially infectious biological material.
To protect the sample being analyzed from becoming contaminated.
To protect the environment

2. Theory of operation
 The biological safety cabinet has a front glass window of
adjustable height, a ventilation system with an electrical
motor, a ventilator and a set of ducts which while
functioning, generate a negative pressure condition inside
the cabinet.
 Five main types of safety cabinets which utilize different air
flow directions.
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5.
Class І Type A
Class II Type A
Class II Type B1
Class II Type B2
Class II Type B3

3. Installation
 A laboratory area protected from air currents from
windows or air-conditioning systems.
 An electrical connection equipped with a ground pole.
 There must be free space for placing the feet and its
height must be adequate.

4. General maintenance
Weekly
Monthly
 Decontaminate the work
 Clean the exterior
surface and the interior
surfaces of the cabinet with
70% ethanol.
 Clean the front glass door and
the surface of the ultraviolet
lamp, using a mild detergent.
surfaces, especially the front
and the upper part using a
piece of damp cloth in order
to remove the dust.
 Disinfect the surface of the
lower compartment with 70%
Ethanol or a suitable
disinfecting solution.
 Verify the state of the service
valves.

5. General maintenance
Annually
 Check the intensity of the UV
lamp with a radiometer.
 Test the state of the
fluorescent lamp

6. Functional evaluation
Electrical
 Voltage, Amperage
 Motor/ventilator
 Illumination –
Fluorescent, Ultraviolet
 Alarms
 Switches, Electrical outlet, cables
and connectors
 Verification of operation
temperature. Verify noise level and
vibration.
 the operational hours of the lamps
and their light intensity. Requires a
radiometer.
 Testing of state and calibration.
 Control of state and integrity
 quality of the contact and available
voltages

7. Functional evaluation
Physical
 State of filters and pre-filters
 There must be no leaks, in
 Seals/gaskets
 There must be no leaks.
 Sliding window
 Must be able to be moved
the filtering material or in the
seals.
smoothly and possible to stop
at the selected positions.

8. Functional evaluation
Operational
 Flow velocity
 Noise level
 Pressure differential in the
HEPA filter
 Control of velocity according
to the class and type of
cabinet. Requires an
anemometer (wind gauge).
 Requires audiometer
 Take a manometer reading of
the cabinet.

9. Functional evaluation
Condition of the installation area
 Temperature
 Humidity
 Requires thermometer:
approximately 20–22 °C.
 Requires thermometer:
approximately 20–22 °C.
 Cleanliness
 Must be adequate.
 Air currents
 There must be no air currents
to affect the working of the
cabinet.

10. Cabinet certification
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Air tightness test.
HEPA filter leak tests.(HEPA: High Efficiency Particulate Air.)
Temperature increase test.
Noise test.
Luminous intensity test.
Vibrations test.
Protection test
Stability test.
Vertical flow velocity test.
Entry flow velocity test.
Smoke test.
Drainage escape test.
Motor/ventilator system functioning test.
Electric system test.

11.  End of Biological Safety Cabinet.