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 #: 14 Grid Opening Size: 0.01124 Client Sample #: 14 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 N or < EDS (Nonadb No F B C M >=05 p i '=5p Chrys Amphibole Nonasb Ambig/ND No Coord Elements) ( <5p

z-

I Struct = > 0.5p >5:1 Aspect Ratio Grib acceptance:

A- Positive diffraction pattern properties conforming to <50% undissolved filter, overlapped or folded Totals <10% particulate coverage >50% coverage ate laboratory identification criteria observed least 20 unfolded or overlapped grid squares <5% F B C j M >6p ■/= 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 = Matnx Actinolite Non-Identified NSD = No Structures Detected

CONFIDENTIAL, CITY_21MC100_003403553 SUBJECT TO PROTECTIVE ORDER NO. 2, SEPT. 2008

NYC-WTC_000181765