LaMotte DC1600 Colorimeter User Manual
Page 40
PROCEDURE
1.
Rinse a clean colorimeter tube (0967) with sample water. Fill to the 10 mL line with sample.
2.
Select setting 6 on “Select Wavelength” knob and press “30 Second Read” button.
3.
Insert tube into colorimeter chamber and adjust to 100%T with “Set Blank” knob. This is the 100%T blank. (See
Note 2.)
4.
Remove tube from colorimeter. Use the 0.5 mL pipet (0353) to add 0.5 mL of *Sodium Arsenite Solution (4128).
Cap and mix.
5.
Use the 1.0 mL pipet (0354) to add 2 measures of *Acid-Zirconyl SPADNS Reagent (3875). Cap and mix thoroughly.
6.
Insert tube into colorimeter and press “30 Second Read” button. Record %T as soon as the reading stabilizes.
7.
Consult calibration chart to determine fluoride concentration in parts per million (ppm).
NOTE: For best results perform the test procedure on clear, colorless, fluoride free water. This reagent blank should
read 26%T. If the reagent blank reading is less than 26%T, add the difference to all subsequent unknown sample
readings. If the result is greater than 26%T subtract the difference from all subsequent unknown sample readings.
EXAMPLES:
Reagent Blank = 24%, 26 - 24 = 2. Add 2 to unknown sample result. 56 + 2 = 58%T
Reagent Blank = 29%, 29 - 26 = 3. Subtract 3 from unknown sample result. 56 - 3 = 53%T.
DC1600 FLUORIDE CALIBRATION CHART
%T
9
8
7
6
5
4
3
2
1
0
90
80
70
60
2.00
1.95
1.90
1.85
1.80
1.75
1.71
1.66
1.61
1.57
50
1.52
1.48
1.43
1.39
1.34
1.30
1.26
1.22
1.18
1.13
40
1.09
1.05
1.01
0.97
0.93
0.90
0.86
0.82
0.78
0.74
30
0.70
0.66
0.61
0.57
0.53
0.48
0.43
0.38
0.33
0.27
20
0.21
0.15
0.08
0.00
10
0
40