LaMotte 1964-EPA, Manual

Page: 56 / 80

8. Add 5 drops of *DPD 1B Free
Chlorine Reagent (P-6741). Cap
and mix. Solution will turn pink if
free chlorine is present. Read within
30 seconds.
9. Open the meter lid. Insert tube into
chamber. Align the index notch on
the positioning ring with the index
arrow on the meter. Close lid, press
*
I
OK
to select
Scan Sample .
F r e e C h l o r i n e ( L )
* S c a n S a m p l e
1 6 : 0 2 : 1 9
0 1 / 0 4 / 0 5
10. Record the result as Free Chlorine.
T o t a l C h l o r i n e ( L )
1 . 0 0
p p m
* S c a n S a m p l e
‚
1 6 : 0 2 : 1 9 0 1 / 0 4 / 0 5
11. Remove the tube from the
chamber. Add 5 drops of *DPD 3
Total Chlorine Reagent (P-6741).
Cap and mix. 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.
56 CALIBRATION & ANALYSIS • CHLORINE
DPD
3
DPD
1B