E-mails 2003 M. Gilsenan

NYC 9/11 Public Portal Document

Asbestos Air Sample Collection and Analysis

1. All asbestos air sampling methodologies shall be in accordance with the applicable sections of Title 15, Chapter 1 of the Rules of the City of New York and AHERA. (see reference in Table 1)

2. Asbestos air samples shall be analyzed in accordance with EPA 40 CRF Part 763 Final Rule (AHERA) using a transmission electron microscope (TEM) and reported as shown in Attachment 1. For the TEM analysis, two size fractions should be reported, a fraction that represents fibers >0.5 microns and a fraction that represents fibers >5 microns. The fraction that represents the fibers >5 microns is considered to be the PCM equivalent (i.e., PCMe) that should be compared to the primary clearance value of 0/iTiiri9 s/cc. In addition, the asbestos air samples shall be analyzed in accordance with NIOSH 7400 for standard PCM analysis. These results shall be reported on a separate sheet. The detection limit shall be 0.K fi'cc.

3. A turnaround time of 24 hours is required for all samples.

Asbestos Air Monitoring

1. Five (5) ambient air samples shall be collected outside but in the general vicinity of the work site. Samplers shall be placed in reasonable proximity to the building and away from obstructions, vents, and drafts that may unduly affect airflow.

2. Five (5) air samples shall be collected per day during cleanup activities. The flow rate shall be set at the minimum collection flow rate specified by the manufacturer for the sampling pump. The flow rate shall not exceed 3 liters per minute. A minimum sampling volume of 3600 liters shall be collected.

Samples shall be collected at isolation barriers outside the work area, the clean room of the worker/waste decontamination facility, and outside of the building.

3. Sample collection methodologies shall be in accordance with Title 15, Chapter 1 of the Rules of the City of New York (RCNY) and AHERA regarding dociunentation and sample locations and the requirements set forth herein regarding the rates of flow, and required volumes to achieve the necessaiy analytical sensitivity.

4. Sampling equipment shall be placed at representative locations and away from obstruction. Sampling cassette must be placed on a tripod and not taped to existing surfaces. All air sampling equipment shall be pre- and post- calibrated to insure accurate air sampling volumes. __ 5. The Air Sampling Technician shall perform clearance air sampling after the areas are free of dust accumulations as determined by the Project Monitor. All surfaces must be completely dry prior to the start of sampling. Clearance air sampling shall be performed at each apartment. Five samples shall be collected in each apartment and two samples shall be collected at the first floor lobby. The elevator shaft shall be cleared separately. Clearance air monitoring shall be performed after the 4 of 6

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