Baker SterilGARD II SG400STD - Using Ancillary Equipment; About the HEPA Filters

13. Disconnect the hot plate and frying pan from
the electrical outlets.
14.
Allow the cabinet to stand for a minimum of
hvo hours, preferably overnight.
"
15. If it is :not possible to attach a flexible hose,
add the same amount of N~HC0
3
as of
paraformaldehyde to the frying pan. Tum on
the frying pan and the cabinet blower until
the NH
4
HC0
3
has dissipated.
16. Let the cabinet stand for at least one hour
before opening the seals.
Using Ancillary Equipment
The rule to keep in mind is that the more
equipment is in the cabinet, the greater will be the
air turbulence it causes. The turbulence resulting
from equipment and materials can disrupt the
designed airflow and reduce the effectiveness of
the cabinet. When you use equipment which
rotates, vibrates or heats, be sure to place it at the
rear of the work area if possible. This will
minimize the turbulence in the access opening.
Avoid using equipment which exceeds the
amperage limit of the outlets in the work area.
The limit for the SterilGARD'"II is a total of 5.0
amps. The outlets are protected by a ground-fault
interrupter and a circuit breaker. The circuit
breaker is a self-resetting type which will reset
automatically after an improper load has been
removed. Each G. F. I. outlet includes a lighted
indicator which monitors the state of the outlet.
To control the outlets, use the controls on the
front canopy.
Certain procedures, such as those involving
some types of centrifuge or blender, can generate
a large volume of aerosols capable of penetrating
the air safetv barrier. In order to estimate how
much aerosol you may create when you are using
common procedures or ancillary equipment,
please refer to "Potential for AccidentallVlicrobial
Aerosol Transrnission in the Biological
Laboratory", Dimmick, R.L., Vogl, W.F. and
Chatigny, JvLS., 1973. Biohazards ffi Biological
Research, p. 246-267, Hellman, A .. Oxman, M.N .
. and Pollack, R editors. Cold Spring Harbor
' Laboratory.
17
Using a blender
Homogenizing cultures with a blender can
create an en01~nous aerosol load. so special
precautions must be taken. It is essential to
decontaminate surfaces and carry out an air purge
both before and after the use of the blender. Do
not perform other research activities or leave your
arms in the cabinet while the blender is in
operation. And wait at least five minutes after the
blender has come to a complete stop before you
open its cover.
The air safety barrier could possibly be
penetrated by the high concentration of contam-
inated particles if the blender were opened during
or just after operation. In that case, the
surrotmding laboratory would very likely be
con tam ina ted.
Using a centrifuge
Srna!! clinical centrifuges can also create severe
turbulence because of their rotating action. They
disrupt the airflow within the cabinet <md also at
the opening, sometimes allowing contaminated
air to escape L.nto the laboratory. Do not perform
other research activities or leave your arms in the
cabinet while the centrifuge is operating. Wait at
least five minutes after the centrifuge has come to
a
complete stop beiore you open its cover.
Conduct surface decontamination and air purge
both before and after using the centrifuge.
If you use a centrifuge often or work with fairly
hazardous agents, we recommend that you
purchase a laminar flow safety cabinet which has
been modified to hold various centrifuges. In
these modified units, the centrifuge is placed in a
well which is recessed so as to hold air turbulence
to a minimum.
About the HEPA Filters
The HEPA (High Efficiency Particulate Air)
filter is
one of the essential components of a
biological
safety cabinet. It is the shield which
stands between the environment and the
experimental agent.
The
HEP A filter consists of a continuous sheet
of glass fiber pleated over rigid corrugated
separators and rnounted in a frame. It is very