Basic Documentation

Containment Units
Class and
Type of
Biosafety
Cabinet:
Class I Class II
Type A
Class II
Type B3
Class II
Type B1
Class II
Type B2
Class III
Minimum
average face
velocity of air
entering front
opening of
cabinet:
75 fpm
(0.38 m/s)
75 fpm
(0.38 m/s)
100 fpm
(0.51 m/s)
100 fpm
(0.51 m/s)
100 fpm
(0.51 m/s)
(Not
Applicable)
Fully Enclosed
Cabinet
Contaminatio
n protection
cabinet
provides for
biological
substances:
None* Good Good Very Good Very High Absolute
Method of
protecting
biological
substances
None
HEPA
filtered air
composed
of a mix of
room and
recirculated
cabinet air
flows over
substance.
HEPA
filtered air
stream
composed
of a mix of
room and
recirculated
cabinet air
flows over
substance.
HEPA
filtered air
stream
composed
of
recirculated
room and
some
cabinet air
flows over
substance.
HEPA
filtered air
stream
composed
of non-
recirculated
room air
and
containing
no
chemical
vapors from
within
cabinet.
HEPA filtered
air stream
composed of
non
recirculated
room air which
is also
environmentally
conditioned
within the
cabinet.
Volatile toxic
chemicals
allowed in
cabinet:
Yes if the
cabinet
exhaust is
hard
ducted
outside and
utilizes a
partial front
closure
panel.
None Small
quantities
only
Small
quantities
only
Moderate
quantities
only
Quantities as
needed
Radionuclides
allowed in
cabinet:
Yes if the
cabinet
exhaust is
hard ducted
outside and
utilizes a
partial front
closure
panel.
None Trace
quantities
only
Trace
quantities
only
Small
quantities
only
Quantities as
needed
* Class I Biosafety cabinets are often used to house equipment that generates aerosols such as centrifuges and
fermentors. They are typically used if no contamination protection is required for the biological substances within.
Siemens Building Technologies, Inc. 43