LaMotte PHOSPHONATE TEST KIT OP-DR - Manual (Page 3)

PRO CE DURE
1.
Fill the test tube (0778) to the 10 mL line with sample water.
2. Add 1 drop of Sodium Thiosulfate (6155).
3. Add the exact number of drops of *Hydrochloric Acid (6130)
recorded in Step D above.
4. Use the 0.1 g measuring spoon (0699) to add one level measure of
Xylenol Orange Powder (6165). Swirl to dissolve. The solution will
turn yellow.
5. Replace the regular cap on the bottle of Thorium Nitrate (6158PS)
with the special perforated dispenser cap (0601). Fill the Direct
Reading Titrator (0378) with this reagent. Insert the Titrator into
the center hole of the titration tube cap.
6. While gently swirling the titration tube, slowly press the plunger to
titrate until the solution changes from yellow to pink.
7. Read the test result directly from the scale where the large ring on
the Titrator meets the Titrator barrel.
8. Replace the regular cap on the Thorium Nitrate bottle for storage.
9. For most accurate results, a blank test should be run on a sample of
the water containing no Phosphonate. Any result from this blank
test should be subtracted from the result recorded in Step 7 above.
10. This test has been calibrated for Dequest 2006. When a different
compound is to be tested, the amount of Thorium Nitrate added
should be multiplied by a conversion factor to determine ppm
Phosphonate.
Phosphonates Compound Name Factor
Dequest 2000 AMP(NTP) 0.8
Dequest 2006 NaAMP 1.0
Dequest 2010 HEDP(A) 0.6
Belcor 575 0.5
11. If any other Phosphonate compound is used, the factor must be
determined experimentally using standard solutions of that
compound.