Silica analysis report revision, Residential Sampling Project, Dec 2001

NYC 9/11 Public Portal Document

107Haddon Avenue EMSL Analytical, /nc»- f^estmoni, NJ. 08108 (856) 858^800 12/7/01 Attention; U.S.EPA .EQ Financial Services Division 1200 Pennsylvania Avenue NW Maildrop 273 4R Washington, DC. 20460

Project; Residential Sampling Ref. Number: 360100635 Revision 120201

Crystalline Particle Analysis Performed by X-Ray Diffraction (XRD) Silica Analysis by Method NIOSH 7500 Nuisance Duxt Analyte Airbante Analyte Anolyte "/» Analytical I Siunple Sample Weight Cotte. Weight Cent Ajialjlc Sensitivity Sample ID Identification Particle ID Volume (mg) (mg/m^ (.me) (tng/m’) (ms/m*) (L)

[R)FF-R2-10 Qairti 1226 0.034 0.0277 <.004 <AS N/A 0.0033 Cfislobalite <0.012 <AS 0.0154 T ridyinHe N/A N/A N/A Calcite <0,004 <AS 0.0051 Portland/ Lime <0.02 <A3 0.0256 Gypsum <0.004 <AS 0.DDS1 Mica <0.011 <AS 0.0141 Halilo <0.006 <AS 0.0077 Fibrous-Glass N/A N/A N/A

(R]BRF-A-10 Ouartr 0 N/A M/A <0:004 Crisiobalile <0:012 Tridyrnha N/A Calcite <0.004 Portland/ Lme <0.02 Gypsum <0.004 Mica <0.011 Halite <C.OO6 Fibrous Glass M/A

[R]eRF-S-10 Quart? 0 N/A N/A <0.004 CfislQbalile <0.012 Trtdymile N/A Calcite <0.004 Portland/ Lime <0.02 Gypsum <0.004 Mica <0.011 Halite <0.006 Fibrous Glass N/A

John Ne'n'ton 28 November. 01 Analyst Date of Analysis Oi-scbiiturr: The lah.ar.nory can only verify the concenJretJon oi stlica on the filter and not the final (.oncentratjon due to data obtuned by non-taioraiory personnel, fn the absence of a bull; dust sample, flic specific form of crysLiltine silica can not be determined. Hence, alpha-quarti, the most prevalent form of cry-siaJlinc silica, will be assumed. = Ijtss IhuntltecLded value The lowest reportable value is equivalent to the Analytical Sensitisity which is mJeiilited from the lowest reproducible conaentratioa of silica detectable bytlic in.sutimenl, .AIHA Accredited - talulrilory ID bl00192

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