Land 4500 MKII Premier, Operation And Maintenance Manual

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Model 4500 Premier Dust and Opacity Monitor
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B3-4 Isokinetic Calibration
The Model 4500 Premier measures the opacity of dust and smoke emissions. As explained in the Reference
manual, this value is related to the dust density in the stack, through the Beer-Lambert law (see section C1-
2). In order to measure the dust density, it is necessary to know the Dust Gain (parameter 'k'), which
relates optical density to dust density. Dust Gain is found by comparing with the measured Optical
Density/Dust Density found by an isokinetically sampled dust measurement.
The Model 4500 Premier is designed to be easily calibrated relative to an isokinetic sample. Two methods
may be used, depending on whether the instrument is to be calibrated relative to a single sample, or
multiple samples. A single sample is simple to collect and analyse, but more often a series of
measurements are taken under different load conditions or at different points across the diameter of the
stack. This method gives a more accurate representation of the overall dust burden in the stack.