LaMotte SMART3 Colorimeter - Manual (Page 106)

APPLICATION: Drinking, surface, and saline waters; swimming pool water;
domestic and industrial waters and wastes.
RANGE: 0.0–20.0 ppm Bromine
MDL: 0.25 ppm
METHOD: In buffered sample bromine reacts with diethyl-p-phenylene
diamine (DPD) to produce a pink-red color in proportion to
the concentration of bromine present.
SAMPLE
HANDLING &
PRESERVATION:
Bromine in aqueous solutions is not stable, and the bromine
content of samples or solutions, particularly weak solutions,
will rapidly decrease. Exposure to sunlight or agitation
will accelerate the reduction of bromine present in such
solutions. For best results start analysis immediately after
sampling. Samples to be analyzed for bromine cannot be
preserved or stored.
INTERFERENCE: The only interfering substance likely to be encountered in
water is oxidized manganese. The extent of this interference
can be determined by treating a sample with sodium
arsenite to destroy the bromine present so that the degree
of interference can be estimated.
Iodine and chlorine can also interfere, but these are not
normally present unless they have been added as sanitizers.
BROMINE, UDV SMART3 Test Procedures 11.10
Test P
rocedures