NYC-WTC_000233286

NYC 9/11 Public Portal Document

(b) TEM Clearance Criteria. If TEM is the selected method of clearance air sampling and analysis, the clearance criteria and sampling protocols of AHERA shall be used. If PCM air sample analysis results exceed the satisfactory clearance air criteria under this Part, then TEM analysis of the entire set of clearance air samples may be used, provided that a standard accepted laboratory analysis method is used that shall report each air sample result in fibers per cubic centimeter, for appropriate correlation to the original unsatisfactory PCM clearance air sample results and the established background level(s). When AHERA TEM air sampling protocols are not used (i.e. TEM analyses of failed PCM air samples), PCM clearance criteria apply

(c) Submission of Satisfactory Clearance Air Sample Results. The air sampling asbestos contractor shall submit to the Commissioner, all satisfactory PCM clearance air sample results along with background results, if they are greater than or equal to 0.01 fibers per cubic centimeter. The air sampling asbestos contractor shall also submit to the Commissioner, all sets of satisfactory TEM analyses of previously unsatisfactory PCM clearance air sample results, along with the unsatisfactory PCM results. These air sample results shall be submitted, within two (2) business days of receipt of satisfactory clearance air results, to the Commissioner in care of the appropriate district office of the Asbestos Control Bureau, where the project takes place.

56-4.12 Unsatisfactory Clearance Air Sample Results. If the regulated abatement work area clearance air sampling results are unacceptable, the following requirements apply: (a) If the results of the inside work area group of air samples are unsatisfactory, recleaning of regulated abatement work area surfaces using wet methods, followed by another drying time period and then collection and analysis of an additional full set (both inside and outside work area samples) of clearance air samples is required (See Section 56-9.2). (b) If only the results of the outside work area group of air samples is unsatisfactory, clean-up of surfaces outside of the regulated abatement work area using HEPA- vacuums and wet-cleaning methods shall be performed prior to collection and analysis of an additional group of outside work area clearance air samples as required by Section 56-9.2. (c) This recleaning/clean-up and sampling process shall be repeated until satisfactory clearance air sampling results have been achieved for all asbestos project non-exempt regulated abatement work areas throughout the entire work site.

12 NYCRR56 Subpart 4, Page 39

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