NYC 9/11 Public Portal Document
RoofClean-Up
Application: This procedure utilizes wet methods and careful hygiene protocol for cleaning roofs contaminated
wi± asbestos containing material (ACM).
1. The entire roof shall be considered the work area. All abatement will be performed by NYSDOL licensed
contractors with NYC DEP certified workers.
2. A changing area consisting of two adjacent step-off pads located on the roof immediately adjoining the roof
entrance/exit. This area shall consist of a clean pad and a change pad. The clean pad shall be adjacent to the
b: Iding interior access way (or at the point of entry to the roof for exterior access). The change pad shall be
adjacent to the contaminated roof areas. Each pad (change pad and clean pad) shall consist of two layers of
10-mil reinforced plastic on the roof/access way surface and shall be large enough to facilitate changing and
decontamination as described herein. A minimum of 4’ x 4’ is recommend, though the exact configuration
will be specific to the roof.
3. Workers shall first step from the uilding intenvr (or exterior at tiie point of entry to the roof) directly onto
the clean pad. On the clean pad, each worker shall be double suited with disposable coveralls, plastic
booties, gloves, and head coverings. Rubber boots may be used instead of the plastic booties. The boots
shall be wet wiped and HEPA vacuumed prior to leaving the roof. Each worker shall wear a minimum of a
half-face air-purifying respirator equipped with HEPA cartridges.
4. All penetrations at the roof shall be cleaned by wet methods/HEPA vacuum and sealed with polyethylene
sheeting.
S. Roof cleanup shall begin at the entrance/exit and proceed in a path working away from the entrance/exit.
Water shall be the primaiy engineering control to minimize the potential for fiber release.
6. Roof surfaces shall be wetted and then wet cleaned using wet wiping techniques with water, mops, rags,
brushes, etc. HEPA vacuuming may also be used as alternative to or in combination with wet cleaning.
7. Throughout the procedure, all personnel entering or existing the roof shall observe the personal
decontamination practices. Attention shall be paid to limiting uimecessary walking on or disturbance of
material on the roof. These personal decontamination procedures shall be adhered to strictly in order to
minimize the potential for spreading contamination to the interior of the buildings.
8. Solid nonporous objects, such as metal patio furniture, plant potters, and plastic furniture cushions, shall be
wet wiped with damp rags. Wooder objects such as decking shall be HEPA vacuumed, wet wiped, and
lightly brushed with a bristle brush utilizing simultaneous misting and local HEPA exhaust. Woven materials
shall either be disposed as ACM or bagged and removed off-site for proper laundering in accordance with 29
CFR 1901. 1(X)1. Potted plants with visual contamination should be disposed as ACM waste unless the
owner requests decontamination. Potted plants will be repeatedly rinsed, and provisions shall be made to
catch the runoff water (i.e. into AC*. .sposal bags or by using rags and HEPA wet-vacuums).
9. After completion of the above, the entire roof shall be carefully washed.
10. Air Monitoring shall be performed by NYSDOL licensed a Third Party Air Monitoring firm with certified
workers. The Third Party Air monitoring firm shall perform a visual inspection to confirm the absence of
ACM or debris after die areas are completely dry. Clearance air monitoring shall not be required if all
samples collected during the work were found to be below 70 s/mm^.
NYC-WTC_000150861
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