NYC-WTC_000233286

NYC 9/11 Public Portal Document

remain and the area shall be cleaned of all debris/residue using HEPA vacuuming and wet wiping. If beadblaster or a similar abrasive type of abatement method is used, full work area preparation, including establishment of negative pressure filtration systems, shall be required and this abatement may be done as one of the first types of abatement and then the flooring area abated shall be re­ plasticized with a double-layer of 6-mil fire retardant plastic sheeting, to be utilized as a dropcloth during the remaining abatement. (iii) Temporary Walls. New temporary hardwalls used to separate an enclosed regulated abatement work area into smaller regulated abatement work area enclosures shall be constructed as per Section ICR 56-7.11(b). Existing columns, I beams and interior walls may be used to support or to act as part of the new containment walls provided that the existing walls, columns, and I beams to which these temporary walls are to be attached or used shall be completely abated prior to the erection of these new containment walls to allow this attachment. Caulk, fire-retardant expandable foam or duct tape shall be used to form an airtight seal for these partitions.

(a) Airlock. Each newly enclosed regulated abatement work area shall have an attached airlock as defined in Section 56- 2.1, and the airlock shall be constructed at the enclosure entrance, as per section 56-7.5(b)(11). Each enclosure and airlock shall be cordoned off twenty-five (25) feet from its perimeter. Critical openings within the cordoned off area shall be covered with two (2) layers of six (6) mil fire retardant polyethylene in conformance to Section 56-7.11 (a).

(iv) Intermediate completions. On completion of each type of asbestos abatement within these work area enclosures, a complete single clean of all surfaces in the entire area - ceiling, walls and floors - shall be performed by HEPA vacuuming and wet wiping. No final clearance air samples shall be required for each individual type of material abatement, until the last type of ACM, PACM or asbestos material is abated. Each intermediate completion shall include a visual inspection for completeness by the supervisor. Results of the visual inspection and time of intermediate completion shall be documented by the supervisor in the daily project log. (V) Final Required Cleaning. A complete single clean of all surfaces in the entire area - ceiling, walls and floors, followed by a visual inspection as described in Subpart 56-9 shall be performed by HEPA vacuuming and wet wiping, after all abatement is complete.

12 NYCRR56 Subparts, Page 80

CITY_21MC100_0 03235100

NYC-WTC_000233366