387
Method 8178
PHOSPHORUS, REACTIVE (0 to 30.0 mg/L PO
4
3-
)
Amino Acid Method
*
For water, wastewater, seawater
* Adapted from Standard Methods for the Examination of Water and Wastewater.
1. Enter the stored
program number for
reactive phosphate
(PO
4
3-
), amino acid
method.
Press:
PRGM
The display will show:
PRGM ?
Note: For most accurate
results, perform a Reagent
Blank Correction using
deionized water (see
Section 1).
2. Press: 85 ENTER
The display will show
mg/L, PO4 and the
ZERO icon.
Note: For alternate forms
(P, P
2
O
5
), press CONC.
3. Fill a 25-mL sample
cell with 25 mL of sample.
4. Add 1 mL of
Molybdate Reagent using
a 1-mL calibrated dropper.