Form 37714 Rev 2002
Page 7 of 13
Flow Rate Through Sorbent Tubes
1. Attach the tubing on the CPC outlet (side of the CPC without a label) to the pump inlet. Attach
the Adjustable Low Flow Holder to the CPC inlet (marked “To Sample”).
See Figure 4.
2. Break tips off the representative sorbent tubes and insert the tubes into the rubber sleeves on
the holder
(arrow on each tube pointing toward pump)
. Place unopened tubes in any unused
ports to “seal” them.
3. Label all representative tubes and ports.
4. Using flexible tubing, connect the exposed end of the first active tube to be calibrated to the
calibrator outlet (suction port).
5. Using a small screwdriver, loosen and turn the brass flow adjust screw (
see above right
)
directly beneath the port holding the first active tube to be calibrated (
clockwise
to increase,
counterclockwise
to decrease) until the calibrator indicates the method-specified flow rate.
Do
not adjust the flow rate on the pump.
Note:
For tri and quad models, first rotate each anti-tamper
cover to expose the flow adjust screws, then adjust the appropriate one until the calibrator indicates the
desired flow (Figures 3 and 5).
6. Repeat Steps 4 and 5 for each active representative tube.
Note:
Changing the flow on one tube will
not
affect the flow rate through the remaining tubes.
7.
Once flow is calibrated for each active tube, it is recommended practice to re-check the flow rate
through representative tubes before removing them. Any adjustment should be minimal.
Screw
Screw
Figure 5.
Cut-away of Tri/Quad
Adjustable Low Flow Tube Holder
Turn screw on
tube holder to
adjust flow.
Flow adjust screws
Connect
CPC to
pump inlet,
tube holder
to CPC, and
tube inlet to
calibrator.
Figure 4.
Calibration Train with Quad Adjustable
Low Flow Tube Holder
Suction port
chek-mate Calibrator
Quad tube holder
Tube holder outlet
Pump
inlet
CPC inlet (marked
“To Sample”)