Hach DR/850, Procedures Manual, Page: 379 / 460

379
Method 8190
PHOSPHORUS, TOTAL
(0.00 to 3.50 mg/L PO
4
3- )
For water, wastewater and seawater
PhosVer 3 with Acid Persulfate Digestion
*
USEPA Accepted for reporting wastewater analysis
**
Test ’N Tube Procedure
* Adapted from Standard Methods for the Examination of Water and Wastewater .
** Procedure is equivalent to USEPA Method 365.2 and Standard Method 4500-P B, 5 and P.E.
1.
Turn on the DRB200
Reactor. Heat the reactor
to 150 °C.
Note: See DRB200
instrument manual for
selecting preprogrammed
temperature applications.
2.
Enter the stored
program number for
total phosphorus,
(PO
4
3
-
), Test ‘N Tube.
Press:
PRGM
The display will show:
PRGM ?
Note: For most accurate
results, perform a Reagent
Blank Correction using
deionized water (see
Section 1).
3.
Press:
82 ENTER
The display will show
mg/L, PO4 and the
ZERO icon .
Note: For alternate forms
(P, P
2
O
5
), press the CONC
key.
4.
Insert the COD/TNT
Adapter into the cell
holder by rotating the
adapter until it drops
into place. Then push
down to fully insert it.
Note: A diffuser band
covers the light path holes
on the adapter to give
increased performance.
The band should NOT be
removed.
5.
Use a TenSette Pipet
to add 5.0 mL of sample
to a Total and Acid
Hydrolyzable Test Vial.
Note: Adjust the pH of
stored samples to 6-8
before analysis.
6.
Using a funnel, add
the contents of one
Potassium Persulfate
Powder Pillow for
Phosphonate to the vial.
7.
Cap tightly and
shake to dissolve.
8.
Place the vial in the
DRB200 Reactor. Heat
the vial for 30 minutes.