Labconco 3980200, User Manual

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17
Chapter 3: Getting Started
Set the Face Velocity with the
Speed Control Adjustment
Adjustment of the speed control gives the correct face velocity and
is located behind the front panel. The face velocity should be from
75 to 105 fpm for biohazardous operations. (Consult your Safety
Officer for airflow recommendations for your application).
Containment is maximized at a setting within this range. Working
at the lowest face velocity appropriate for the application will give
the quietest operation. Face velocity measurements are made using
an anemometer. An electric anemometer can be obtained from
your laboratory supply dealer. Face velocity measurements should
be taken in accordance with the
Industrial Ventilation Manual .
Using a small Phillips screwdriver, adjust the speed control to give
the required face velocity. See Figures 6-1 and 6-2 in Chapter 6 to
locate the speed control. The face velocity is increased by turning
the speed control counter clockwise and clockwise to decrease face
velocity.
Validating the Vented Enclosure
To determine the actual face velocity at the sash opening, airflow
velocity readings are taken. This should be done across the sash
opening of the enclosure in accordance with the
Industrial
Ventilation Manual . (See Appendix E) The “average face
velocity” is achieved by taking readings in two rows across the
enclosure with the readings 6" from the ends and evenly spaced
every 12"; the first row is 3" down from the upper sash foil and the
second row is 3" up from the work surface. A total of four
readings will be taken for the 2' enclosure, six readings taken for
the 3' enclosure and eight readings taken for the 4' enclosure and
then averaged. Refer to Chapter 2 for proper airflow volumes for
your particular model.
The Purifier enclosures have been tested at Labconco’s airflow test
facility per ASHRAE 110-1995. All enclosures achieve an “as
manufactured rating” of less than 0.05 part per million (ppm) at 4
liters per minute (lpm); AM <0.05 (Consult Labconco for
individual ratings). For “field use” ASHRAE testing contact
Labconco for a certified on-site contractor. Labconco also
performed extensive ASHRAE testing to validate the enclosures
for gas containment. For copies of these validation reports, contact
Labconco Customer Service.