LaMotte SMART3 Colorimeter - Manual (Page 224)

PROCEDURE
NOTE: Place Dispenser Cap (0692) on *Mixed Acid Reagent (V-6278). Save this
cap for refi ll reagents.
1. Press and hold until colorimeter turns on.
2. Press ENTER to select TESTING MENU.
3. Select ALL TESTS (or another sequence containing 067 Nitrite-N LR) from
TESTING MENU.
4. Scroll to and select 067 Nitrite-N LR from menu.
5. Rinse a clean tube (0290) with sample water. Fill to the 10 mL line with sample.
6. Insert tube into chamber, close lid and select SCAN BLANK.
7. Remove tube from colorimeter and pour off 5 mL into a graduated cylinder or
similar. Discard the remaining sample.
8. Pour the 5 mL sample from the graduated cylinder into the colorimeter tube.
Use graduated cylinder or similar to measure 5 mL of *Mixed Acid Reagent (V-
6278) and add to tube. Cap and mix.
9. Use the 0.1 g spoon (0699) to add two measures of *Color Developing
Reagent (V-6281). Cap and mix by gently inverting for 1 minute. Wait 5 minutes
for maximum color development.
10. At the end of the 5 minute waiting period, mix, insert tube into chamber, close
lid and select SCAN SAMPLE. Record result.
11. Press to turn colorimeter off or press
EXIT
button to exit to a previous
menu or make another menu selection.
NOTE: To convert nitrite-nitrogen (NO
2
–N) results to ppm nitrite (NO
2
– ), multiply
results by 3.3.
NITRITE NITROGEN, Low Range SMART3 Test Procedures 11.10
Test P
rocedures