LaMotte SMART3 Colorimeter - Manual (Page 173)

DISSOLVED OXYGEN
WINKLER COLORIMETRIC METHOD • CODE 3688-SC
QUANTITY CONTENTS CODE
30 mL *Manganese Sulfate Solution *4167-G
30 mL *Alkaline Potassium Iodide Azide *7166-G
30 mL *Sulfuric Acid 1:1 *6141WT-G
1 Sample Tube, screw cap 29180
1 Cap 28570
*WARNING: Reagents marked with an * are considered to be potential health
hazards. To view or print a Material Safety Data Sheet (MSDS) for these reagents
go to www.lamotte.com. To obtain a printed copy, contact LaMotte by e-mail,
phone or fax.
Dissolved oxygen is vital to the survival of aquatic organisms. Naturally present,
dissolved oxygen enters the water when plants photosynthesize. Wind and wave
action also cause oxygen from the air to dissolve into water. Dissolved oxygen is
consumed by aquatic animals and by the oxidation, or chemical breakdown, of
dead and decaying plants and animals. The concentration of dissolved oxygen
in natural waters can range from 0 to 14 ppm and is effected by temperature and
salinity.
APPLICATION: This method is applicable for the determination of
dissolved oxygen in drinking water, all surface waters and
wastewater.
MDL: 0.6 ppm
RANGE: 0.0–10.0 Dissolved Oxygen
METHOD: This method uses the azide modifi cation of the Winkler
Method with a colorimetric determination of the yellow
iodine produced from the reaction with the dissolved
oxygen.
INTERFERENCES: The presence of other oxidizing agents may cause
positive interferences. Reducing may cause negative
interferences. Nitrite interferences are eliminated with the
azide modifi cation.
SMART3 Test Procedures 11.10 DISSOLVED OXYGEN
Test P
rocedures