LaMotte LEAD IN AIR TEST KIT - Manual (Page 9)

solutions in presence of acids because the highly toxic HCN gas is
evolved.
6. Cap and shake vigorously for 10-15 seconds. Remove cap and allow
test tube to stand undisturbed for 1 minute. After 1 minute the layers
will separate, producing a yellow to orange layer on top. No pink or
red should be present in the bottom layer. If a pink or red color is
present, rewash tube with dilute acid, rinse with distilled water and
start procedure over.
7. Dilute to 10 mL line with pH adjusted Absorbing Solution from Step
3. Cap and shake vigorously for 30 seconds.
8. Allow test tube to stand undisturbed for 1 minute. If bottom layer
remains cloudy shake another 10-15 seconds. Check the pH to ensure
pH is between 9 and 11.
9. Insert test tube into the Lead In Air Comparator (4418). Match
sample color to index of color standards. Record the index number
which gives the proper color match.
10. Repeat Steps 3-9 on a blank of deionized water and subtract result
obtained from test result.