LaMotte SMART Spectro Spectrophotometer - Manual (Page 159)

PROCEDURE
Use universal sample holder.
1. Press and hold
ON button until spectrophotometer turns on.
2. Scroll to and select PROGRAMMED TESTS.
3. Scroll to and select ALL TESTS (or another sequence containing
54 Lead
) from TESTING MENU.
4. Scroll to and select 54 Lead from menu.
5. Rinse a tube (0290) with sample water. Fill to 10 mL with sample.
6. Insert the tube into chamber, close lid and select SCAN BLANK.
7. Remove the tube from Spectro. Use the Syringe (0807) to remove 5mL of
sample from tube. Discard remaining sample.
8. Add the 5 mL of sample in the syringe to the tube. Add 5 mL Ammonium
Chloride Buffer (4032) to fill the tube to the 10 mL line. Swirl to mix.
9. Add 3 drops *Sodium Cyanide, 10% (6565). Swirl to mix.
10. Use the 0.5 mL pipet (0353) to add 0.5 mL PAR Indicator (4033). Swirl to
mix.
11. Use the 0.5 mL pipet (0353) to add 0.5 mL Stabilizing Reagent (4022).
Cap and mix.
12. Insert tube into chamber, close lid and select SCAN SAMPLE. Record
result in ppm as Reading A.
13. Remove tube from Spectro. Add 3 drops DDC Reagent (4034). Cap and
mix.
14. Insert tube into chamber, close lid and select SCAN SAMPLE. Record
result in ppm as Reading B.
15. ppm Lead = Reading A–Reading B
16. Press
OFF button to turn the spectrophotometer off or press EXIT button
to exit to a previous menu or make another menu selection.
þNOTE: For best possible results, a reagent blank should be determined to
account for any contribution to the test result by the reagent system. To
determine the reagent blank, follow the above test procedure to scan a
distilled or deionized water blank. Then follow the above procedure to
perform the test on a distilled or deionized water sample. This test result is
the reagent blank. Subtract the reagent blank from all subsequent test results
of unknown samples. It is necessary to determine the reagent blank only
when a new lot number of reagents are obtained.
Lead 2/2 SMART SPECTRO TEST PROCEDURES 05.04