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 (liters): 1920 Lab Group #: 7827 Filter Type / Filter Area: MCE 385 mm^ Lab Sample #: 12 Grid Opening Size: 0.01124

Client Sample #: 12 Area Examined: 0.04496 mm^

GRID BOX: Magnification: 20,000 GRID ID: Accelerating Voltage: 100 KeV # Grid Openings: 4 Analysis Date: 5/21/02

Analysis Performed By: MARK PEYSAKHOV

GO. Structure Structure Type Length ID of Structure NorN EDS (Nonadb No F B C M >=05 M :>=5(J Chrys Amphibole Nonasb Ambig/ND No Coord <5M Elements)

^<3 ZX

Struct = > 0.5,u >5:1 Aspect Ratio Grid acceptance: 7 = Positive diffraction pattern properties conforming to <50% undissolved filter, overlapped or folded Totals laboratory identification criteria observed <10% particulate coverage >50% coverage ate least 20 unfolded or overlapped grid squares <5% F B C M >5|J V= EDS spectrum conforming to laboratory holes or opaque areas identification criteria observed Chrysotile AMPHIBOLES Amphibole F = Single Fiber Amosite B = Bundle (<3 libers <1 fiber diameter apart Crocidolite Ambiguous C = Cluster (>3 Intersections) Anthophyllite Non-Asbestos T remolite M = Matrix Actinolite Non-ldentified NSD = No Structures Detected

CONFIDENTIAL, CITY_21MC100_003403551 SUBJECT TO PROTECTIVE ORDER NO. 2, SEPT. 2008

NYC-WTC_000181763