LaMotte SMART3 Colorimeter - Manual (Page 115)

PROCEDURE–FREE CHLORINE
1. Press and hold until colorimeter turns on.
2. Press ENTER to select Testing Menu.
3. Select ALL TESTS (or another sequence containing 016 Chlorine Liq DPD)
from TESTING MENU.
4. Scroll to and select 016 Chlorine Liq DPD from menu.
5. Rinse a tube (0290) with sample water. Fill to 10 mL with sample.
6. Insert the tube into chamber, close lid and select SCAN BLANK.
7. Remove the tube from colorimeter.
8. Add 5 drops of DPD 1A Free Chlorine Reagent (P-6740).
9. Add 5 drops of *DPD 1B Free Chlorine Reagent (P-6741). Cap and mix.
10. Insert tube into chamber, close lid and select SCAN SAMPLE. Record result
as ppm free chlorine.
PROCEDURE–TOTAL CHLORINE
11. Add 5 drops of *DPD 3 Total Chlorine Reagent (P-6743). Cap and mix.
NOTE: For wastewater samples, Standard Methods for the Examination
of Water and Wastewater recommends waiting 2 minutes for full color
development.
12. Insert tube into chamber, close lid and select SCAN SAMPLE. Record result
as ppm total chlorine.
13. Subtract the Free Chlorine reading from the Total Chlorine reading to determine
ppm combined chlorine.
14. Press to turn the colorimeter off or press
EXIT
to exit to a previous
menu or make another menu selection.
NOTE: For best possible results, a reagent blank should be determined to account
for any contribution to the test result by the reagent system. To determine the
reagent blank, follow the above test procedure to scan a distilled or deionized
water blank. Then follow the above procedure to perform the test on a distilled or
deionized water sample. This test result is the reagent blank. Subtract the reagent
blank from all subsequent test results of unknown samples. It is necessary to
determine the reagent blank only when a new lot number of reagents is obtained.
SMART3 Test Procedures 11.10 CHLORINE, DPD Liquid
Test P
rocedures