Silica analysis report revision, Residential Sampling Project, Dec 2001

NYC 9/11 Public Portal Document

107Haddon Avenue EMSL ^EMSL Analytical, /nc.- fi^estmont, NJ. osios (856) 858^800 12/7/01 Attention: 1/.S.ER4 HQ Financial Services Division 1200 Pennsylvania Avenue NW Maildrop 2734R Washington, DC. 20460

Project: Residential Sampling Ref. Namber: 360100635 Revision 120201

Crystalline Particle Analysis Performed by X-Ray Diffraction (XRD) Silica Analysis by Method MOSH 7500 NuKonce Dust Airborne Analyte .Sample Sample Analyte Anajyic % Analytical Sample ID Identification Particle ED Volume Weljhl Cone. Weiebt Cone. Aniilyte S«i$jtivity (ms) (mc/m’) (ma) (OTjj/m’) (ms/m') (L) (RJBTF-A-IO Quartz 0 0.814 WA <0.004 Crfeioballie <0.012 Tridymile N/A CaleilG <0.004 Portland/ Limo <0.02 Gypsum <0.004 Mica <0.011 Malte <0.006 Fibrous Gloss N/A

lRlBTF-B-10 Quartz 0 0.082 <0.004 Cristobarrle <0.012 Tridymile nja Calcite <0 004 Portland/ Lima <0.02 Gypsum <0.004 Mica <0.011 Halite <0.006 Fibrous Glass I41A

John Nev>ton 28 November, 01 Analyst Dal e of Analysis Disclaimer The laboralory can only veri^ the concentration of silica on die filler told not the fijti! concentration due to dau obtained by non-Uboialory pcratmticl. In the absence of a bulk duaiuunplc, the specific form nf crysullinesiliea can not be detamiacd. Hence,, al'plia-quanz, the most prevalent form of crytlujlinc silica, will he aasum.td. - Less than die stated voluc "1110 lowest reportable value is couivaient to the Analytio.il Sensitivity whui is eslculated from the lowest reproducible ctmcereiation of silica detectable by die instrument. AIHA.Accredited - Laboratory ID SIOOISI

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