Connecting The Exhaust; Final Connections And Tests - Baker SterilGARD II SG400STD Operator's Manual

Connecting the Exhaust
The SterilGARD@II cabinet can operate
with filtered exhaust air enteri11g directly
i11to the room, or with filtered exhaust
duded to the outdoors. Details of these
alternatives are as follows:
Exhaust into the room -
If the cabinet exhausts its air directly into the
laboratory instead of ducting it to the outside,
it is important that there be adequate space
between the top of the cabinet and the ceiling.
If the solid ceiling is located less than 4" from
the exhaust filter, it may restrict the air and
limit the cabinet's intake velocity.
Although 4'" of top clearance may be
sufficient for day-to-day operation of the
cabinet, it will be difficult to obtain airflow
testing information. At least 12" of clearance
on the top of the cabinet is recommended for
reliable rneasure.rnent of ai.rflovv.
Never use ttle top of the cabinet or the work
area for storage purposes, and never use
flac'Timable, explosive or toxic vapors or
gases, or substances which generate them,
unless a qualified safety professional has
evaluated the risk The filter removes only
particulates and not gases, thus causing the
recirculation of these within the cabinet.
Attach the long-legged exhaust filter guard,
located in the rear, to prevent inadvertent
blocking of the filter area.
Remove the two nuts from the back of the
exhaust filter guard, and then remove nvo
nuts from the front and two from the rear of
the exhaust filter housirtg on top of the unit.
Install the legs on the studs at the rear of the
exhaust filter housing. Tighten them dovvn
with the previously-removed nuts.
Install the exhaust filter guard, setting the
front clips on the front studs of the exhaust
filter housing. Tighten then1 down
vvith
previously' rernoved nllts.
I'-Jov~_.·
secure the filter g-uard to the ='is-inch
NPT nipples in the top.
9
Exhaust to the outside -
Whenever possible, the filtered exhaust
should be cormected to its own separate
exhaust svstem. If it m11st be channeled into a
multi-du~t
system, make sure that the'system
is not a recirculating one. You will, of course,
also want to make sure that the system can
handle the volume of air required to pass
through it, and that there is sufficient static
pressure for proper cabinet function.
The exhaust requirements of the 4-foot
SterilGARD'fl are 268 CFM at .02"-.04" water
column suction directly above the exhaust
filter before any reductions, elbows or other
restrictions. If using Baker's hard exhaust
transition (ET400), add 0.10" water column.
If a Baker thimble exhaust transition is being
used, 322 CFM minimum at 0.10" water
column.
The exhaust reguirernents of the 6·-foot
SteriiGARD-!1 are 408 CHv! at .02"-.04" water
column suction directly above the exhaust
filter before any reductions, elbows or other
restrictions. If using Baker's hard exhaust
transition (ET600), add 0.10" water column.
If a Baker thimble exhaust transition is being
used, 462 CFM minimum at ()_22" water
column.
You may want to install an indicator light or
some other safety device to give warning if
the exhaust system fails. A properly
designed duct system includes an airtight
damper to balance the air and also to shut off
the duct for purposes of cabinet
decontamination. The Baker Cornpanv offers
a transition duct piece for connecting the unit
to the exhaLLSt system. Call for details.
For further infonnation, refer to the National
Sanitation Foundation's Standard J"Jo. 49 and
other guidelines regarding ·ventilation.
Final Connections and Tests
1. The pl'untbi_ng connection to the service
petcocks. rrrust be made with great care
because the effluent from a safety cabinet
rr1ay
be biologically hazardous. VVhen
present, petcocks are piped ·vvithin the