NYC-WTC_000233286

NYC 9/11 Public Portal Document

public access, and signage shall be installed as per section 56-7.4(c). Openings within the cordoned off area or space/room (except access entrance) shall be covered with two (2) layers of six (6) mil fire retardant polyethylene in conformance with Section 56-7.11 (a). (iii) Negative Air. Manometers consistent with the requirements of section 56-7.8(a)(4), are required for negative pressure tent enclosure regulated abatement work areas with OSHA Class I abatement. Negative air shall be maintained at four (4) air changes per hour for non-friable and glovebag abatement tent enclosure work areas. Eight (8) air changes shall be maintained for friable gross removal tent enclosure work areas. If a HEPA-filtered vacuum is used for a Minor size abatement tent enclosure work area to maintain the required air changes, after final cleaning is completed 20 minutes shall elapse, then ventilation may be stopped, clearance air samples collected, and the tent sealed until results are read. If air sample results are unacceptable, ventilation shall be reestablished, the area recleaned and new samples taken. (2) Fire-Retardant Spray Plastic. Fire-retardant spray plastic may be used in lieu of two (2) layers of six (6) mil plastic sheeting as required by 56- 7.11 (e), under the following conditions: (i) Critical barriers are installed per section 56-7.11 (a) of this Part. (ii) The fire-retardant spray plastic is used, applied, maintained and removed in accordance with the manufacturer’s detailed procedures by persons who have been trained by the manufacturer or others authorized to perform such training. Proof of appropriate training shall be located at the work site and shall be produced upon verbal request of the Commissioner or his or her duly authorized representative. (iii) Application shall be made to result in a dry thickness of not less than six (6) mils. (3) Special Projects. See Subpart 56-11 regarding work area preparation requirements for special projects. These projects include exterior non- friable ACM roofing, siding, caulking, glazing compound, transite, tars, sealers, coatings, and other NOB ACM abatement, abandoned intact pipe/duct/conduit wrap and cut abatement, flooring and mastic abatement, pre-demolition abatement, demolition with asbestos in place, in-plant operations abatement, emergency project abatement and Minor size project abatement.

(4) Removal of Ceilings and Components. Suspended ceiling and components that exist below friable ACM or PACM material, and that are not themselves ACM or PACM, shall remain in place until the remainder of the regulated abatement work area has been plasticized, negative air

12 NYCRR56 Subpart?, Page 69

CITY_21MC100_0 03235089

NYC-WTC_000233355