LaMotte COD Plus Colorimeter 1922-EX2 - Manual (Page 101)

PROCEDURE - LOW RANGE
A. PREPARATION OF HR REAGENT
NOTE: The quantity of Indigo Blue Stock solution (3989) supplied will
prepare one batch of HR Reagent for the High Range Ozone procedure or five
batches of HR Reagent for the Low Range Ozone procedure.
1.
Use the 50 mL graduated cylinder to carefully add 45 mL of *Ozone Buffer
(3991) to amber glass bottle marked HR Reagent (0680).
2. Use the 5 mL transfer pipet (0329) and pump (30527) to add 5 mL of
Indigo Blue Stock Solution (3989) to the amber glass bottle. Cap and mix.
B. DETERMINATION OF OZONE
3.
Use the 1.0 mL transfer pipet (2-2170) and pump (30527) to add 1.0 mL
of HR Reagent to each of 2 clean tubes (0290).
4. If chlorine is present add 3 drops Chlorine Inhibitor (3990) to each tube.
Cap tubes.
5. Take one of the prepared tubes (0290) and sampling apparatus (0681) to
sampling site.
6. Lower end of tubing of sampling apparatus to desired depth. Slowly
withdraw and depress plunger several times to purge syringe and tubing.
Slowly withdraw plunger to fill purged syringe.
7. Remove plastic tubing from syringe. Remove cap from the prepared tube.
Place tip of syringe against inside of the prepared tube. Slowly depress
plunger and fill to the 10 mL line and cap. This is the Sample Tube.
NOTE: DO NOT SHAKE OR INVERT THE SAMPLE.
8. Fill the second prepared tube (0290) to the 10 mL line with ozone free
water. This is the Reagent Blank.
9. Press and hold ON button until colorimeter turns on.
10. Press ENTER to start.
11. Press ENTER to select TESTING MENU.
12. Select ALL TESTS (or another sequence containing 18 Ozone-LR)
from TESTING MENU.
13. Scroll to and select 18 Ozone-LR from menu.
14. Insert the Reagent Blank tube into chamber, close lid and select SCAN
BLANK .
15. Insert reacted Sample Tube into chamber, close lid and select SCAN
SAMPLE . Record result.
16. Press
OFF button to turn colorimeter off or press EXIT button to exit to a
previous menu or make another menu selection.
NOTE: HR Reagent must be made fresh each week. If reagent is refrigerated, it
may be kept up to 3 weeks.
OZONE 2/3 COD PLUS TEST PROCEDURES 6/02