LaMotte SMART Spectro Spectrophotometer - Manual (Page 90)

PROCEDURE–FREE CHLORINE
Use universal sample holder.
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
15 Chlorine) from TESTING MENU.
4. Scroll to and select 15 Chlorine 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 all but a suffi cient amount of sample
water to cover a tablet. Add one *Chlorine DPD #1 Instrument Grade Tablet
(6903A). Crush tablet with a tablet crusher (0175), then add sample water
until tube is fi lled to 10 mL line. Cap tube and shake until tablet has dissolved.
Solution will turn pink if free chlorine is present. Wait 15 seconds, but no longer
than 30 seconds. Mix.
8. Insert tube into chamber, close lid and select SCAN SAMPLE.
PROCEDURE–COMBINED CHLORINE
Use universal sample holder.
9. Add one *Chlorine DPD #3 Instrument Grade Tablet (6197A) to sample from
Step 8 above. Crush tablet with tablet crusher (0175). Cap tube and shake until
tablet dissolves. An increase in color represents combined chlorine.
NOTE: For wastewater samples, Standard Methods for the Examination
of Water and Wastewater recommends waiting 2 minutes for full color
development.
10. Insert sample into chamber, close lid and select SCAN SAMPLE. Record
result as Total Chlorine.
11. Subtract free chlorine reading from total chlorine reading to obtain
concentration of combined chlorine.
12. Press the OFF button to turn off the spectrophotometer or press the EXIT
button to exit to a previous menu or make another menu selection.
SMART Spectro Test Procedures 2.11 CHLORINE, BROMINE, IODINE
Test P
rocedures