LaMotte SMART Spectro Spectrophotometer - Manual (Page 179)

PROCEDURE
Use universal sample holder.
þNOTE: Place Dispenser Cap (0692) on *Mixed Acid Reagent (V-6278).
Save this cap for refill reagents.
1. Press and hold
ON button until spectrophotometer turns on.
2. Scroll to and select PROGRAMMED TESTS.
3. Scroll to and select ALL TESTS (or another sequence containing
67 Nitrite-N LR
) from TESTING MENU.
4. Scroll to and select 67 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 Spectro 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
OFF button to turn spectrophotometer off or press EXIT button to
exit to a previous menu or make another menu selection.
þNOTE: To convert nitrite-nitrogen (NO
2
–N) results to ppm nitrite (NO
2
),
multiply results by 3.3.
Nitrite-Nitrogen–LR 2/2 SMART SPECTRO TEST PROCEDURES 05.04