Hach DR/700 - Page 268

50-18
IRON, TOTAL, continued
USING ACCUVAC AMPULS
1. Install module
50.01
in a DR/700.
Note: If samples cannot
be analyzed
immediately, see
Sampling and Storage
following these steps.
Adjust pH of stored
samples before analysis.
2. Press: l/O
The display will show
500 nm
and module number
50.01
Note: Determination of
total iron needs a prior
digestion; use the mild,
vigorous or Digesdahl
digestion (Section I).
3. After 2 seconds
the display will show
a program number,
concentration units,
decimal position and
the zero prompt. If
necessary press the
UP ARROW key until
the lower display
shows program
number
50.04.1
4. Fill a cell with 10
mL of sample (the
blank). Cap. Collect
at least 40 mL of
sample in a 50-mL
beaker.
Note: For turbid
samples, treat the blank
with one 0.2-gram
scoop of RoVer Rust
Remover. Swirl to mix.
5. Fill a FerroVer
AccuVac Ampul with
sample.
Note: Keep the tip
immersed while the
ampul fills completely.
Note: For proof of
accuracy, use a 1.0 mg/L
iron standard solution
(preparation given in the
Accuracy Check) in
place of the sample.
6. Quickly invert the
ampul several times
to mix. Wipe off any
liquid or fingerprints.
Note: An orange color
will form if iron is
present.
Note: Accuracy is not
affected by undissolved
powder.