Envirco BSC - Manual (Page 13)

13
APPENDIX 1
DOWNFLOW/HAND INTAKE SETTINGS
BIOHAZARD CABINETS-Class II
INFLOW MEASUREMENT USING THE THERMOANEMOMETER METHOD
MODEL
CABINET
TYPE
CALCULATED
HAND INTAKE
VELOCITY
DOWNFLOW
HIGHEST READING
AND LOWEST
READING
11228 BBC 86 A2 0.505 －0.555m/s
0.305 - 0.355m/s ±20 ％ OF AVERAGE
To set the air velocity of the opening work area correctly, we emphasize again that only
qualified persons using calibrated equipment may carry out the adjustments. If you have
difficulties, please contact the manufacturer.
NOTE: Adjustments must be made in conjunction with the down flow air velocity
profiling section and it is necessary to have a balance test between them.
3.2.3 Downflow air velocity
The equipment’s airflow should be balanced and generally the only requirementis outlined in
Section 3.2. However, as the HEPA filter becomes loaded, the readings on the static pressure
monitor will increase (located on the control panel). The fan speed needs to adjust so it can
build up to the correct air velocity within the working chamber. The equipment is designed with
an air damper. We can control the exhaust and inflow air ratio by adjusting the positions of the
damper. The setting is done in the factory and generally needs no adjustment. The
equipment’s correct settings and the testing data are in feet per Minute (FPM)
NOTE: Adjustments to the balance of the air velocity should be made by a certified
Technician.
3.2.4 Pressure test:
When testing pressure, the PAO test port can be used to introduce the pressurizing gas
(generally air).
3.3 Sterilization:
Before sterilizing the equipment, do not remove the front grids or the drainage valve.
You must sterilize the equipment per the following:
-------Before operation
-------Before replacement of the filter
-------Before performance testing (unless the equipment is new and has never been used)
-------Before moving the equipment