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 #: 7344 Filter Type / Filter Area: MCE 385 mm^ Lai) Sample #: 10 Grid Opening Size: 0.01124 Client Sample #: 10 Area Examined: 0.04496 GRID BOX:____ Magnification: 20,000 GRID ID: Accelerating Voltage: too KeV # Grid Openings: 4 Analysis Date: 4/6/02

Analysis Performed By: MARK PEYSAKHOV

GO. Structure Structure Type Length IDofStructure Nory EDS No__ (Nonadb F B C M .=05 p ->=5p Chrys Amphibole —Nonasb — -AmbigftJD . No Coord <5p Elements)

^3 3 i

Struct = > 0.5p >5:1 Aspect Ratio Grid acceptance: '/= 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% T F B C M ’5p '/= EDS spectrum conforming to laboratory holes or opaque areas identification 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 = No Structures Detected

CONFIDENTIAL, CITY_21MC100_003402688 SUBJECT TO PROTECTIVE ORDER NO. 2, SEPT. 2008

NYC-WTC_000181720