Asbestos sampling summary report, Nov 2001

NYC 9/11 Public Portal Document

Summary of Asbestos Sampling Results Page 2 of 3 Address: 225 Rector Place Date sampled: November 16, 2001

f/cc using the PCM methodology, additional analysis was performed to determine whether any of the fibers were asbestos. In this building, additional analysis was not warranted since the air sampling results were not greater than 0.003 f/cc.

Results of Phase Contrast Microscopy (PCM) testing of air at 225 Rector Pl, Nov. 16, 2001 Area Sampled Outside Common Residence 1 Residence 2

Sample Numbers A-0-6 A-C-6 A-Rl-6 A-R2-6 A-R2-X-6* Concentration of Fibers < 0.001 < 0.001 <0.001 < 0.001 at 225 Rector Pl (f/cc)** 0.002 * Concentration of Fibers <0.001 to 0.001 <0.001 to 0.002 <0.001 to 0.003 <0.001 to 0.003 (f/cc) in air at comparison locations NYC Re-occupancy 0.01 0.01 0.01 0.01 Standard (f/cc)*** * Denotes a second air sample taken in the same location for quality control purposes. ** f/cc is fibers in each cubic centimeter (cc) of air. This is calculated from the number of fibers seen on the air filter and the volume of air pulled through the filter measured in cubic centimeters of air. *** New York City Department of Environmental Protection asbestos clearance criteria for post-abatement work (Rules of the City of New York, Title 15, Chapter 1)

ASBESTOS DUST TEST RESULTS In general, the dust and debris samples were examined by two different laboratory methods for asbestos fibers. Polarized Light Microscopy (PLM) and Transmission Electron Microscopy (TEM). PLM is used to define asbestos containing material in dust and debris. A material is considered to be asbestos containing material if it contains more than 1% asbestos using the PLM method. The PLM method only counts the larger asbestos fibers. Therefore, if results by PLM were not greater than 1% asbestos, the sample was then analyzed by the TEM method that does count the smaller fibers. However, TEM analysis is not used for regulatory purposes for dust samples.

No asbestos fibers were found in the dust samples from the hallway or in the two residences by the PLM laboratory method. Not enough dust was found outdoors, so a sample was not collected. Further analysis by the TEM method detected asbestos in the hallway dust at levels of less than 1%. The TEM method did not detect any asbestos fibers in the dust from the two residences.

Fibrous materials in dust found by PLM analysis: Polarized Light Microscopy identifies asbestos fibers by shape and optical characteristics. Other fibers such as fabric (synthetics), paper (cellulose) and fiberglass may be identified in the analysis. The laboratory analyst counts

CONFIDENTIAL, CITY_21MC100_003423635 SUBJECT TO PROTECTIVE ORDER NO. 2, SEPT. 2008

NYC-WTC_000176135