Hach DR/850, Procedures Manual, Page: 271 / 460

271
Method 10031
NITROGEN, AMMONIA, High Range, Test ‘N Tube
(0 to 50 mg/L NH
3
-N)
For water, wastewater, and seawater
Salicylate Method
*
1.
Enter the stored
program number for
nitrogen, ammonia, high
range Test ‘N Tube
(NH
3
-N) method.
Press:
PRGM
The display will show:
PRGM ?
2.
Press:
67 ENTER
The display will show
mg/L, NH3-N and the
ZERO icon .
Note: For alternate forms
(NH
3
), press the
CONC key.
Note: For proof of
accuracy, use a 10-mg/L
nitrogen, ammonia
standard in place of the
sample.
3.
Insert the COD/TNT
Adapter into the cell
holder by rotating the
adapter until it drops
into place. Then push
down to fully insert it.
Note: For increased
performance, a diffuser
band covers the light path
holes on the adapter. Do
not remove the diffuser
band.
4.
Remove the caps
from 2 AmVer Diluent
Reagent High Range
Vials. Add 0.1 mL of
sample to one vial (the
sample). Add 0.1 mL of
deionized water to the
other (the blank).
5.
Add the contents of 1
Ammonia Salicylate
Reagent Powder Pillow
for 5 mL Sample to
each vial.
6.
Add the contents of 1
Ammonia Cyanurate
Reagent Powder Pillow
for 5 mL Sample to
each vial.
7.
Cap the vials tightly
and shake thoroughly to
dissolve the powder.
Note: A green color
will develop if ammonia
is present.
8.
Press:
TIMER ENTER
A 20-minute reaction
period will begin.
* Adapted from Clin. Chim. Acta , 14 403 (1966).