LaMotte SMART Spectro Spectrophotometer User Manual
Page 159
APPLICATION
Drinking and surface waters; domestic and industrial
waters.
RANGE:
0.00–2.00 ppm Fluoride
MDL:
0.05 ppm
METHOD:
Colorimetric test based upon the reaction between
fl uoride and zirconium dye lake. The fl uoride reacts with
the dye lake, dissociating a portion of it into a colorless
complex ion and dye. As the fl uoride concentration
increases, the color produced becomes progressively
lighter.
SAMPLE HANDLING
& PRESERVATION:
Samples may be stored and refrigerated in plastic
containers.
INTERFERENCES:
The following substances produce a positive interference
at the concentration given:
Chloride (Cl–)
Phosphate (PO
4
–3
)
Hexametaphosphate (NaPO
3
)
6
The following substances produce a negative
interference at the concentration given:
Alkalinity (CaCO
3
) 5000
mg/L
Aluminum (Al
3+
)
0.1 mg/L
Iron (Fe
3+
) 10
mg/L
Sulfate (SO
4
–2
)
200
mg/L
Color and turbidity must be removed or compensated
for in the procedure. Temperature should be maintained
within 5°C of room temperature.
FLUORIDE
SMART Spectro Test Procedures 2.11
Test P
rocedures