Summary Of Method - Hach POCKET COLORIMETER II Instruction Manual

Fluoride, AccuVac® Method,
continued

Summary of Method

The SPADNS method for fluoride determination involves the reaction of fluoride
with a red zirconium-dye solution. The fluoride combines with part of the
zirconium to form a colorless complex, thus bleaching the red color in proportion
to the fluoride concentration. This method is accepted by the USEPA for NPDES
and NPDWR reporting purposes when the samples have been distilled. Seawater
and wastewater samples require distillation. See Optional Apparatus on page 1—37
for information on the Distillation Heater and Support Apparatus Set.
Required Reagents
Description Units Cat. No.
®
SPADNS Fluoride Reagent AccuVac Ampuls ............................ 25/pkg .... 25060-25
Water, deionized .................................................................................... 4 L ........ 272-56
Required Apparatus
Beaker, 50 mL, pp................................................................................each .......1080-41
Thermometer, -10 to 110 °C................................................................each .......1877-01
1—36