Accessories
Description
Catalog No.
Rotameter
Measures 4 to 50 L/min on a 4-inch scale
at 3% accuracy (full scale)
320-440
Certificate of Compliance,
optional,
must be ordered when ordering pump
P1501
4. Sample for the desired sampling period.
5. Turn off pump and unplug from wall outlet.
6. Package sample appropriately for shipment to a laboratory (
see BioSampler Operat-
ing Instructions
).
Note:
Sonic flow is attained when a vacuum pump pulls air through an orifice to create a condi
-
tion where the downstream pressure is 52% of the upstream pressure. At this point, air velocity
through the orifice has reached the speed of sound and cannot increase, therefore, the orifice
becomes “critical.” The fixed air velocity at the critical orifice also limits the airflow so that the
condition remains constant regardless of pressure variations in the system. Airflow will remain
constant at vacuum levels ≥ 15 inches Hg.
