Hach DR/850, Procedures Manual, Page: 169 / 460

169
Method 8029
FLUORIDE
(0 to 2.00 mg/L F
-
) For water, wastewater and seawater
SPADNS Method
*
(Reagent Solution or AccuVac Ampuls)
Using SPADNS Reagent Solution
* Adapted from Standard Methods for the Examination of Water and Wastewater. The procedure for this instrument
uses an alternate wavelength outside the accepted 550-580 nm range. The reagents used are the same as those in
the USEPA accepted method.
1.
Enter the stored
program number for
fluoride (F) powder
pillows.
Press:
PRGM
The display will show:
PRGM ?
2.
Press:
27 ENTER
The display will show
mg/L, F and the
ZERO icon.
3.
Pipet 10.0 mL of
sample into a dry 10-mL
sample cell (the
prepared sample).
4.
Measure 10.0 mL of
deionized water into a
second dry sample cell
(the blank).
Note: The sample and
blank should be at the same
temperature (±1 °C).
Temperature adjustments
may be made before or
after reagent addition.
5.
Pipet 2.00 mL of
SPADNS Reagent into
each cell. Swirl to mix.
Note: SPADNS Reagent is
toxic and corrosive; use
care while measuring. Use
a pipet filler.
Note: The SPADNS
Reagent must be measured
accurately.
6.
Press:
TIMER ENTER
A one minute reaction
period will begin.
7.
When the timer
beeps, place the blank
into the cell holder.
Tightly cover the sample
cell with the
instrument cap.
8.
Press:
ZERO
The cursor will move to
the right, then the
display will show:
0.00 mg/L F