Hach DR/700 - Page 626

61-70
OXYGEN DEMAND, CHEMICAL, continued
10. Invert each vial
several times while
still warm. Place the
vials into a rack.
Wait until the vials
have cooled to room
temperature.
Note: If a pure green
color appears in the
reacted sample, the
reagent capacity may
have been exceeded.
Measure the COD and if
necessary, repeat the
test with a diluted
sample or use a higher
range digestion vial.