6
Nitrate (as NO
3
-
) Test Procedure
REMOVE STRIP
Remove one (1)
eXact
®
Strip Micro NO
3
, Part No.
486655
from the bottle before beginning the test. Set the
strip in a dry, convenient place and recap the bottle
immediately.
NO
3
NO3
1
2
5
3
7
TURN METER ON
Press the
ZERO/ON
button to power the meter on; the
display will show all annunciators, then the current
MENU selection, followed by the last reading.
RINSE AND FILL CELL WITH SAMPLE
Add sample water to the
CELL
and use brush to remove any
zinc from previous tests. Rinse the
CELL
at least 3 times with
the water sample you will be testing - rinsing minimizes the
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cell to capacity with the water sample.
SELECT TEST: NO3
Press and re-press the
MENU
button until the display
shows the parameter
NO3
.
Dip the
eXact
®
Strip Micro NO
3
, Part No. 486655
into
the
CELL
and immediately press
READ
. This starts the
20 SECOND
countdown timer. During this time move
the strip in a gentle back and forth motion (approx. 2
strokes/sec).
Remove and discard the strip after “1”
on the display disappears*
. The meter will automatically
start to count up for 600 seconds (10 minutes).
DIP STRIP AND PRESS “READ”
RECORD RESULT DISPLAYED
After the 600 seconds, the cursor will automatically move
across the display while the meter prepares to measure the
sample. Record result displayed (this result is automatically
stored in NO3 Menu).
After testing, rinse cell and clean
with brush.
Press the
ZERO/ON
button. The cursor will move across the
display followed by
0.00 PPM
. Sample is ready for testing.
ZERO METER*
To determine Nitrate value as Nitrogen (NO
3
as N) as used by USEPA, divide displayed result by 4.4.
*
NOTE: When testing outdoors (sunlight), for best accuracy, use the Mixing Cap/Cell Cover when Zeroing and Reading the sample.
FRESH WATER ONLY (Salt level must be less than 400ppm)
6
NOTE: The Zinc metal reduces Nitrate to Nitrite and Nitrite reacts with chromotropic acid and sulfanilamide in acid media and forms a pink color, directly proportional to Nitrite concentration.
4
IMPORTANT NOTE: Need to clean the cell after each experiment with brush and distilled water.
This is very IMPORTANT. If any zinc dust is adhering to the cell wall, it will affect the results.
Finally, wash the sample three to four times before the measurement starts.
