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): 1928 Lab Group #: 7827 Filter Type / Filter Area: MCE 385 mm’ Lab Sample #: 1 Grid Opening Size: 0.01124 Client Sample #: 01 Area Examined: 0.04496 mm^ GRID BOX: Magnification: 20,000 GRID ID: 3 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 Nor 7 EOS No >=05 M Amphibole (Nonadb F B C M >=5p Chrys Nonasb Ambig/ND Elements) No Coord <5u

Struct = > 0.5p >5:1 Aspect Ratio Grid acceptance: A- Positive diffraction pattern properties conforming to <50% undissolved filler, overlapped or folded Totals laboratory identification criteria observed <10% particulate coverage >50% coverage ate least 20 unfolded or overtapped grid squares <5% F B C M >5u V= EDS spectrum conforming to laboratory holes or opaque areas idenlification criteria 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 = Matrix Non-Identified Actinolite NSD = Mo Structures Detected

CONFIDENTIAL, CITY_21MC100_0 03403540 SUBJECT TO PROTECTIVE ORDER NO. 2, SEPT. 2008

NYC-WTC_000181752