Form 37711 Rev 1809
Page 6 of 14
For low flow, turn regulator
valve screw counterclockwise.
Figure 3.
Single Adjustable Tube Holder
with Sample Tube
Low Flow Applications (5 to 500 ml/min)
Using Single Adjustable Tube Holder (Figure 3)
Activate the Regulator for Low Flow
1. Start the pump using the on/off switch
(Figure 2)
, and adjust the flow rate by turning the flow adjustment
screw
(Figure 2)
until the built-in rotameter reads approximately 1.5 L/min.
2. Remove the cap screw covering the regulator valve
(Figure 2)
and turn the exposed screw four to five turns
counterclockwise.
3. Replace the cap screw. The pump is now set for low flow.
Set/Calibrate Flow Rate for Single Tube
• Allow pump to equilibrate after moving it from one temperature extreme to another.
• Charge pump battery completely before calibration and sampling.
• Calibrate/verify pump flow rate before and after each sampling operation using the
tube holder and pump to be used for sampling.
1. Ensure that the battery is fully charged and that the pump has run for
five minutes before calibrating. Leave the pump running.
2. Ensure that the regulator has been activated for low flow and the pump flow rate
is set at 1.5 L/min.
3. Connect the single adjustable tube holder to the pump inlet.
See calibration train
.
4. Insert an opened sorbent tube into the rubber sleeve
(Figure 3)
of the low flow
tube holder
with the arrow on the tube pointing toward the tube holder.
5. Prepare the calibrator.
See calibrator instructions
.
6. Using flexible tubing, connect the exposed end of the sorbent tube to the calibrator
outlet (suction port). Loosen the brass flow adjust screw
(Figure 3)
on the tube
holder. Adjust the flow rate by turning the flow adjust screw (
counterclockwise
to increase, clockwise to decrease
) until the calibrator indicates the desired flow.
Take a minimum of three readings and record the average flow rate, as per OSHA/
NIOSH instructions.
Do not adjust the flow on the pump. Adjust the flow only by using the flow adjust
screw on the tube holder. Observe the flow rate on the calibrator.
7. When calibration is complete, turn off the pump and disconnect the calibration
tubing from the sorbent tube.
Turn screw to
adjust flow.
Flow adjust
screw
Flow adjust
screw
Rubber sleeve
Sorbent tube
Calibration train with tube in adjustable tube holder
Suction port
Pump inlet
