Hach DR/700 Procedures Manual page 267

IRON, TOTAL,
10.
Place the
prepared sample in
the cell holder.
Note: In bright sunlight
it may be necessary to
close the cell
compartment cover.
continued
11.
Press:
READ
The display will
count down to 0.
Then the display will
show the results in
mg/L iron (Fe).
50-17