Chain of Custody for Asbestos Fiber Analysis at P.S. 234M,

NYC 9/11 Public Portal Document

TEM Asbestos (air) Count Sheet Client Name: NYC BOE Volume niters): 1928 Lab Group #: 7827 Filter Type / Filter Area: MCE 385 mm^ Lab Sample #: 4 Grid Opening Size: 0.01124 Client Sample #: 04 Area Examined: 0.04496 mm^ GRID BOX: Magnification: 20,000 GRID ID: Accelerating Voltage: too KeV # Grid Openings: 4 Analysis Date: 5/21/02

Analysis Performed By: MARK PEYSAKHOV

GO. Structure Structure Type Length IDofStnjcture Nor N EDS No >=05 M Amphibole (Nonadb F B C M >=5p Chrys Nonasb Ambig/ND No Coord <5m Elements)

; I 1 i Struct = >0.5p >5:1 Aspect Ratio Grid acceptance: y = Positive diffraction pattern properties conforming to <50% undissolved filter, overlapped or folded Totals laboratory identification criteria observed <10% particulate coverage >50% coverage ale least 20 unfolded or overlapped grid squares <5% F B C M >5m >/= EDS spectrum conforming to laboratory holes or opaque areas identification critena observed Chrysotile ■AMPHIBOLES Amphibole F = Single Fiber Amosite B = Bundle (<3 fibers <1 fiber diameter apart Crocidolite Ambiguous C = Cluster (>3 Intersections) Anthophyllite Non-Asbestos Tremolite M = Matnx Non-Identified Actinolite NSD = No Structures Detected

CONFIDENTIAL, CITY_21MC100_003403543 SUBJECT TO PROTECTIVE ORDER NO. 2, SEPT. 2008

NYC-WTC_000181755