LaMotte OZONE - DPD LIQUID - Manual (Page 3)

CAUTION: DO NOT leave reacted DPD samples in test tubes (0290). Discard sample
and thoroughly rinse tubes. If allowed to remain, DPD will stain tubes, signifi cantly
impairing the operation of the 1200 Colorimeter. If necessary, acid wash, and
vigorously clean glassware with test tube brush and detergent.
DPD CHLORINE TEST METHOD SPECIFICATIONS
APPLICATION
Bottled water, aquatic waters, and non-chlorinated waters.
RANGE
0 to 3.0 mg/L Ozone.
METHOD
In the presence of Iodide, Ozone reacts instantly with the buffered diethyl-p-
phenylenediamine indicator (DPD) to produce a red color in proportion to the amount
of ozone present.
HANDLING & PRESERVATION
Ozone in aqueous solutions, particularly weak solutions, is not stable. Exposure to
sunlight or agitation will accelerate the reduction of ozone. Fill sample containers to
the top and cap tightly. Analyze samples as soon as possible after collection.
INTERFERENCES
Interferences are other oxidizers, such as, chlorine, bromine, iodine and oxidized
manganese. The DPD reagent system used in thes kit has a signifi cant interference
from chlorine. The primary use for this kit is in applications that use only ozone and
not other oxidizing disinfectants in conjunction with ozone.