LaMotte SMART Spectro Spectrophotometer - Manual (Page 179)

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. Empty the tube. Use the Syringe (0807) to add
5mL of sample to the tube.
8. Add 5 mL *Ammonium Chloride Buffer (4032) to fi ll 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.
NOTE: 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 is obtained.
LEAD SMART Spectro Test Procedures 2.11
Test P
rocedures