Hach DR/700 Procedures Manual page 599

NITROGEN, AMMONIA
For water, wastewater, seawater
Salicylate Method*
1.
Install module
number
61.01
in a DR/700.
Note: If samples cannot
be analyzed
immediately, see
Sampling and Storage
following these steps.
Adjust the pH of stored
samples before analysis.
4.
Fill a 25-mL cell
to the 25-mL line
with sample.
Note: For proof of
accuracy, use a
0.20 mg/L NH -N
3
solution (preparation
given in Accuracy
Check) in place of the
sample.
*Adapted from Clin. Chim. Acta. 1966, 14, 403
2.
Press:
I/O
The display will show
610 nm
and module number
61.01
5.
Fill a 25-mL cell
to the 25-mL line
with demineralized
water (the blank).
61-43
Method 8155
(0 to 1.00 mg/L NH
3.
After 2 seconds,
the display will show
a program number,
the concentration
units and the zero
prompt. If necessary,
press UP arrow until
the lower display
shows program
number
61.06.1
6.
Add the contents
of one Salicylate
Reagent Powder
Pillow to each cell.
Cap and invert the
cells several times to
mix.
-N)
3