Hach DR/700 Procedures Manual page 558

BORON,
continued
4.
Accurately pipet
2.0 mL of sample into
another 125-mL
erlenmeyer flask (the
prepared sample).
Note: For proof of
accuracy, use a 4.0 mg/L
boron standard solution
(preparation given in
Accuracy Check) in
place of the sample.
Warning: Do not use a
stoppered or capped
vessel to complete Steps
4 and 5.
7.
Install module
61.01
in a DR/700.
5.
Add 35 mL of the
BoroVer 3-sulfuric
acid solution to each
erlenmeyer flask
using a 50-mL
graduated cylinder.
Swirl to mix
completely.
8.
Press:
I/O
The display will show
610 nm
and module number
61.01
61-2
25 minutes
6.
Wait 25 minutes.
9.
After 2 seconds,
the display will show
a program number,
the concentration
units and the zero
prompt. If necessary,
press the
UP ARROW
key until the lower
display shows
program number
61.01.1