Form 37714 Rev 2002
Page 4 of 13
High Flow Applications (Cont)
5. Cap the sample and send it with blanks and pertinent sampling information to a laboratory for analysis.
6. Verify the flow.
a. Turn on the pump and reinstate the calibration train and sample medium.
b. Take three readings and record the average value as the post-sample flow rate.
Do not adjust the pump flow rate during this step.
c. Compare the pre and post-sample flow rates. Note in sampling documentation if the values differ by more than ± 5%.
Low Flow Applications (5 to 500 ml/min)
• Single-tube sampling requires the All-in-One Low Flow Holder; see the operating instructions for the All-in-One for details on its operation.
• Multiple-tube sampling requires a Constant Pressure Controller (CPC) and a Dual, Tri, or Quad Adjustable Low Flow Tube Holder accessory;
see the operating instructions for the CPC and Adjustable Low Flow Tube Holder for details on their operation.
Using the All-in-One Low Flow Holder (Figure 2)
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.
• Set the flow rate through the pump first and then calibrate the flow rate through the representative
sorbent tube.
• Two small inlet holes on the bottom of the built-in CPC of the All-in-One can become blocked.
Periodically inspect and, if needed, clean with a small pick and blow particles away with a puff of air.
Pump Flow Rate
1. Ensure that the battery is fully charged and that the pump has run for 5 minutes before
calibrating. Leave the pump running.
2. Prepare the calibrator
(see calibrator instructions)
. Using flexible tubing, connect the calibrator outlet (suction port) to the pump inlet.
3.
Set the pump flow rate to 1.5 L/min. Using a small screwdriver, turn the flow adjustment screw on top of the pump
(Figure 1)
,
clockwise
to increase flow or
counterclockwise
to decrease flow, until the calibrator indicates 1.5 L/min.
4. Remove tubing from the pump inlet.
Flow Rate Through Sorbent Tube
1. Attach the Tygon tubing of the All-in-One to the pump inlet.
Note:
If the pump flow faults shortly after the holder is attached, check that
the needle valve is open by using a small flat-head screwdriver to turn the flow adjust screw on the holder
slightly
counterclockwise. If flow fault
continues, check that the two small holes on the bottom of the built-in CPC are not blocked. If needed, clean them with a small pick and blow any
particles away with a puff of air.
2.
Break tips off the representative sorbent tube and insert it into the rubber sleeve on the All-in-One
(arrow on the tube points toward
the holder).
Note:
Ensure that the sorbent tube fits snugly in the rubber sleeve prior to sampling to avoid air leakage. Two sleeves, each with a
different inner diameter, are supplied with the All-in-One.
3.
Using flexible tubing, connect the calibrator outlet to the inlet of the representative sorbent tube in the holder.
See calibration train above
right
.
In the next step, do not shut off flow completely with flow adjust screw or use an oversize screwdriver to
adjust flow — valve or thread seat damage may result.
4.
Do not adjust the flow on the pump.
Adjust the flow rate through the representative sorbent tube
using a small flat-head screwdriver to turn the flow adjust screw on the All-in-One
(counterclockwise
to increase, clockwise to decrease)
until the calibrator displays the method-specified flow rate. Take a
minimum of three readings and record the average flow rate, as per OSHA/NIOSH instructions.
5.
When calibration is complete, turn off the pump by pressing the on/off button. Disconnect the calibrator
and tubing from the representative sorbent tube inlet.
Turn screw on holder
to adjust flow.
Flow
adjust
screw
Calibration train with All-in-One
Low Flow Holder connected
to AirChek 52
All-in-One
Tygon
tubing
Pump
inlet
Flow adjust screw
(needle valve)
Suction
port
