APPENDIX: Jarless Method for Calibration of Cyclone Assemblies
This procedure may be used in the field to calibrate an air sampling pump and a cyclone assembly
without using the one-liter “calibration jar”.
1. Connect the pump to a pressure gauge or water manometer and a light load (adjustable valve or
5-µm filter) equal to 2” to 5” H2
O with a “TEE” connector and flexible tubing. Connect other end of
valve to an electronic bubble meter or standard bubble tube with flexible tubing (See Fig. 2.1).
NOTE: A light load can be a 5-µm filter and/or an adjustable valve. A heavy load can be several 0.8-
µm filters and/or adjustable valve.
2. Adjust the pump to 1.7 L/min, as indicated on the bubble meter/tube, under the light load
conditions (2” to 5” H2
O) as indicated on the pressure gauge or manometer.
3. Increase the load until the pressure gauge or water manometer indicates between 25” and 35” H2
O.
Check the flow rate of the pump again. The flow rate should remain at 1.7 L/min ± 5%.
4. Replace the pressure gauge or water manometer and the electronic bubble meter or standard
bubble tube with the cyclone having a clean filter installed (Fig. 2.2). If the loading caused by the
cyclone assembly is between 2” and 5” H2
O, the calibration is complete and the pump and cyclone
are ready for sampling.