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NYC 9/11 Public Portal Document

FROM : JLV LI.11.\V., FAX NO. : ILI III IL Jan. 08 2000 10:32PM P15

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LEAP byFlame AA9 Method 7082. Issue L dated_ 7& Auaust 1994.

REA©UNTe: EQUIPMENT: 1, Nitric acid, cono.• 1. Sampler. Cellulose ester filter, a.80tm 2. Nitric acid, 10% (viv). Add 100 ml cone. pare size, 37•mm diameter, In cassette WNO,to 600 mL water; dilute to 1 L. filter holder. 3. Hydrogen peroxide, 30% ItO, (w!w), 2. Peasonaleampbng pump, I to 4 Llmin, with reagent grade.- flexible connecting tubing. 4. Calibration stock solution. 1000 agfmI Pb. 3. AtomicAbsorptloh Spectrophotometer with Cummerolal standard or dissolve 1.00 g Pb en air-sastylene burner head and metal In minimum volume of (1+1) NCI and background corro Lion. dilute to I L with 1% (vhr) HCl. Store in a 4. Lead hollow cathode lamp or electrode polyethylene boiSe. Stable: one year. dischargeless limp. 5. Air, compressed, filtered. b. Regulattors, two-stage, for air and S. Acetylene acetylene. 7, Dfsillled or delonited water. 5. 8ealoers.Phillips,126-mL,orGrlftin, 60.mL with watahglass covers. ' 7. Volumetric flasks, 10- and 100•mL." See SPECIAL. PRECAUTIONS. B. Assorted volumetric pipets as needed.'" 9. Hotplate,surface temperature 140'C. 10. Rortlea, Polyethylene, 100•mL. Clean aft glassware with cone, nitric acid end rinsethoraughly with distilled or delonixed WOW before use. SP[CrAL, PRECAN71gNIa: Concentrated niPie acid is an Irritant and may bum Skin. Perform all digestions in a fume hood. Hydrogen peroxide is a strong oxidic agent, a strong acid to the akin. Wear gloves and eye prolft ion. Irritant, and corrosive

SAMPUNf3: 1. Calibrate aeon personal eampnng pt+mp with 8 represen1a W 2. Sample et en eaouretsly known flow nft between 1 and 4 Lhninsampler In line. for tap to f3 h fora tote) sample sire of 200 to 1500 L for TWA mae*Ur& nenta Do not exceed s fitter loading of Ca. 2 mg total dust. SAMPLE PREPARATION:

NOTE 1! The iollOwing sample preparation gave quantitative recovery (see METHOD) t J. Stow 4 through 9 of Method 7300 or other EVALUATION OF teahnlques maybe substituted, especially if several metals are to quantitative be caning single filter. determined on a NOTE 2: The Appendix giros a microwave digestion procedure which may complete recovery of lead ftotn some matticet;, especially epaxyy be necessary far 3. Open the cassette fittsrl'ioiders and mimsfer based paint. 4. Add 3 mL conc. HNC , and 1 mL 30% HO, and the samples and blanks to clean beakers, cover with a watchglass, Start reagent blanks this step. at NOTE: If PbO, Is not present in the sample, the 30% 3. Heat 4n 140'C hotplate until Volume VDs need not be added [2,4]. 6. Resat two more times using 2 rnL is reduced to about 0.5 mL, 7. Heat on 140 °C hotplate until ca. 0.6cono. HNgand I mL 30% i{O2 each time. mL liquid remains. 8. When sample Is dry, rinse the wstehgless and walls of the beataer with 3 to 6 mL 1046 i- OAibw the solution to evaporate to dryness. 9. Cool

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NYC-WTC 000105593