Hach DR/850, Procedures Manual, Page: 380 / 460

380
9.
Carefully remove the
vial from the reactor.
Place it in a test tube
rack and allow to cool to
room temperature.
Note: Vials will be hot.
10.
Use a TenSette
Pipet to add 2.0 mL of
1.54 N sodium
hydroxide to the vial.
Cap and mix.
11.
Clean the outside of
the vial with a towel.
Note: Wiping with a damp
towel, followed by a dry
one, will remove
fingerprints or other marks.
12.
Place the sample
vial in the adapter.
Push straight down on
the top of the vial until it
seats solidly into the
adapter.
Note: Do not move the vial
from side to side as this can
cause errors.
13.
Tightly cover the
vial with the instrument
cap.
14.
Press:
ZERO
The cursor will move to
the right, then the
display will show:
0.00 mg/L PO4
Note: For multiple
samples, zero only on the
first sample. Read the
remaining samples after
adding the PhosVer 3
reagent.
15.
Remove the cap
from the vial. Using a
funnel, add the contents
of one PhosVer 3
Phosphate Reagent
Powder Pillow to the
vial.
16.
Cap tightly and
shake for 10-15 seconds.
Note: The powder will not
completely dissolve.
PHOSPHORUS, TOTAL,
continued