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Standard Operating Procedures (SOPs)
Verifying Flow Rates in Direct Mode
5.3
Verification or audit: Compare the sampler and FP-25 readings. Is
the sampler’s displayed volumetric or standardized flow reading within 2%
of the flow rate displayed by the FP-25?
» If yes, flow verification is complete.
» If no, calibrate the sampler.
5.4
Calibration: Enter the FP-25 flow value into the sampler for each
calibration point. Many air samplers use a 3-point flow calibration with
readings at the nominal flow rate (
e.g.
16.7 lpm), 10% below the nominal
rate (
e.g.
15.0 lpm for a 16.7 lpm sampler) and 10% above the nominal rate
(
e.g.
18.4 lpm for a 16.7 lpm sampler). Some require 5 calibration points.
5.5
Record your data.
6. Tare the FP-25 before calibrating the next sampler. Ensure that no
air is flowing through the device, and one end is open to atmosphere. When
ready, select MENU > TARE.
