LaMotte LEAD IN AIR User Manual

LEAD IN AIR

CODE 7667

QUANTITY CONTENTS CODE

2 x 100 mL *Lead in Air Absorbing Solution *7668-J
50 mL *Lead Reagent #1 *7664-H
25 mL *Lead Reagent #2 *7665-G
25 mL *Sodium Hydroxide, 5N *6533-G
25 mL *Hydrochloric Acid, 1N *6130-G
1 pH Indicator Strips, 0-14 2950-J
1 Pipet, 1.6 mL, glass w/bulb 0305
2 Test Tubes, 10 mL, glass 0843
1 Octet Comparator, Lead 7719

WARNING: Some reagents in this kit are banned for household use.
Reagents marked with a * are hazardous and Material Safety Data Sheets
(MSDS) are supplied. For your safety read label and accompanying MSDS
before using.

NOTE: To compensate for any color produced by the reagents, a blank
should be run on deionized or distilled water. The reading obtained should
be subtracted from test result.

USE OF THE OCTET COM PARA TOR

The Octet Comparator contains eight permanent
color standards. A test sample is inserted into the
openings in the top of the comparator. The sample
can then be compared to four color standards at
once, and the value read off the comparator. For
optimum color comparison, the comparator should
be positioned between the operator and a light
source, so that the light enters through the special
light-diffusing screen in the back of the comparator.
Avoid viewing the comparator against direct sunlight
or an irregularly lighted background.

PRO CE DURE

1. Pour 10 mL of *Lead in Air Absorbing Solution (7668) into clean
impinging apparatus. Connect impinging apparatus to intake of air
sampling pump. Make sure the long tube is immersed in the absorbing
solution. Collect air sample at a rate of 1.0 Lpm for a period of 10
minutes or until a measurable amount of lead is absorbed.

2. At the end of sampling period, measure pH of absorbing solution by
immersing end of pH strip (2950) into solution. Match the color of
the strip to the color chart. If pH is not within desired range (9-11)
adjust by adding drops of *Sodium Hydroxide, 5N (6533) to raise the
pH or drops of *Hydrochloric Acid, 1N (6130) to lower pH. Make
sure the pH is adjusted between 9 and11.

3. With special glass pipet, squeeze rubber bulb and insert pipet below
clear preservative layer in *Lead Reagent #1 (7664). Release bulb and
draw green solution into pipet until solution level is even with line.
Transfer to clean test tube (0843).

4. Carefully add 5 drops of *Lead Reagent #2. Cap and shake vigorously
for 10-15 seconds.

CAUTION: Lead Reagent #2 is an alkaline solution of cyanide and
should be handled with extreme care. Do not dispose of cyanide
solutions in presence of acids because the highly toxic HCN gas is
evolved.

5. Remove cap and allow test tube to stand undisturbed for 1 minute.
The layers will separate, producing a yellow to orange layer on top. If
a pink or red color is present in the bottom layer, rewash tube with
dilute acid and rinse with distilled water. Restart test.

6. Dilute to 10 mL line with pH-adjusted Lead Absorbing Solution
(Step 2). Cap and shake vigorously for 30 seconds.

7. 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 within desired range (pH 9-11).

8. Insert test tube into the Octet Comparator (7719). Match sample
color to a color standard. Record the index number which gives the
proper color match.

9. Repeat Steps 2-9 with deionized water. Subtract result obtained from
test result.