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To improve the calibration accuracy, perform the calibration under actual sampling conditions if
possible.
Flow Rate Calibration Method
An optionally available standard flow meter can be attached to the sampler's intake side.
Calibration at the work site is simplified by using Sibata OFD-1 orifice flow meter (sold separately) as
the standard flow meter (Optionally available round/rectangular adapter for orifice flow meter is
required. A commercially available USB cable A-B type is also required). For calibration method by
using OFD-1, refer to the OFD-1 operation manual. It is possible to use Orifice flow meter
OF-1C/OF-1S as a standard flow meter.
For attachment method, refer to the orifice flow meter operation manual.
The following is manually calibration method by using a standard flow meter such as OFD-1 or
OF-1C/OF-1S.
1. In the calibration mode, set the flow rate span value to 1.000, and return the zero value to 0.000.
2. Return to the main screen, and set the flow rate you wish to calibrate.
3. Press the [START/STOP] button, and start the high volume air sampler.
4. Record the standard flow meter value and the sampler's instantaneous flow rate display.
5. Calculate the span value. (See page 33.)
6. If you are performing a 2 point calibration, set the other flow rate, and proceed from step 3.
7. Switch to the calibration mode, and enter the obtained span value and zero value.
If you are only adjusting the accuracy of a particular flow rate, perform a 1 point calibration.
If you are using the product at multiple flow rate values, perform either a 1 point or 2 point
calibration depending on the circumstances.
For a 1 point calibration, only change the span value. For a 2 point calibration, change both the
span value and zero value.
Atmospheric Temperature Calibration Method
Calibration can similarly be performed with respect to the atmospheric temperature sensor. Use a
standard thermometer, and place it near the atmospheric temperature sensor.
1. In calibration mode, set the atmospheric temperature span value to 1.000, and return the zero
value to 0.000.
2. Set the mode display to atmospheric temperature display. (See page 21.)
3. Record the standard thermometer value and the equipment's atmospheric temperature display.
4. Calculate the zero value.
5. If you are performing a 2 point calibration, establish a different temperature environment, and
proceed from step 2.
6. Switch to calibration mode, and enter the obtained span value and zero value.
For a 1 point atmospheric temperature calibration, only change the zero value. If you change the
span value, this will adversely affect the accuracy.
For a 2 point calibration, change both the zero value and span value.
The temperature sensor region is not waterproof, so never perform atmospheric temperature
calibration when it is wet.
