Chapter 5
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Orion AQUAfast Reagent Chemistry Instructions for Orion AquaMate
Thermo Scientific
Orion AquaMate Spectrophotometer User Manual
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79
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During testing (blank, reagent blank and sample measurement) and one point calibration
procedures the same vial should be used, as different vials may exhibit minor tolerances.
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The calibration solution and water samples should have the same temperature (+/- 1 °C).
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As the test result is highly dependent on exact sample and reagent volumes, the sample
and reagent volumes should always be measured using a 10 ml or 2 ml volumetric pipette
(class A).
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The accuracy of the test methods decreases above a level of 1.2 mg/l fluoride. Although
the results are sufficiently accurate for most applications, more exact results can be
achieved using a 1:1 dilution of the sample prior to use and subsequent multiplication of
the result by 2.
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SPADNS reagent solution contains arsenite. Chlorine concentrations up to 5 mg/l do not
interfere.
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Seawater and wastewater samples must be distilled.