Fax cover sheet from J.C. Broderick & Associates, Oct 2001

NYC 9/11 Public Portal Document

H. H. ENCLOSURE (Not Applicable)

Enclosure constitutes construction of a permanent (that is, for the life of the building), air-tight, impact-resistant, solid structure of new construction materials which must be built around the asbestos covered pipe or structure to prevent the release of asbestos-containing materials into the area beyond the enclosure and to prevent these materials from casual contact during future maintenance operations. The enclosure shall not alter the existing fire rating and shall be flame resistant and meet the flame spread and smoke generation requirements of federal, state and local guidelines.

1. The requirements of this section are set forth in order to prevent the contamination of the building environment which may be caused by improperly performed asbestos enclosure work. The following procedures shall be adhered to: i. Before constructing the enclosure, all electrical conduits, telephone lines, recessed lights, and pipes in the area shall be moved to ensure that the enclosure will not have to be reopened later for routine or emergency maintenance. If for any reason, lights or other equipment cannot be moved, removal of the asbestos-containing materials rather than enclosure shall be the appropriate control method to use; ii. Enclosure walls shall be made of tongue and groove boards, boards with spine joints, or gypsum boards having taped seams. All joints between the walls and ceiling of the enclosure shall be caulked to prevent the escape of asbestos fibers; iii. The underlying structure must be able to support the weight of the enclosure. Suspended ceilings with laid-in panels do not provide air- tight enclosures and shall not be used to enclose structures covered with asbestos-containing materials; iv. The surface of the asbestos-containing materials which will be disturbed during the installation of hangers, brackets or other enclosure supports shall first be sprayed with amended water or a removal encapsulant using a low pressure airless spray; v. Power drills or other tools which may disturb asbestos- containing materials shall be equipped with or used in conjunction with HEPA vacuum filters; vi. Loose and hanging asbestos-containing materials shall be removed while damp and disposed of in accordance with federal, state and local regulations; vii. After the installation of hangers, brackets or other supports and before the asbestos-containing material is enclosed, asbestos- containing materials shall be repaired, using materials which do not contain asbestos; viii. Enclosures for asbestos-containing materials shall be identified by signs, labels, color coding or some other mechanism to warn persons who may be required to disturb the enclosure that asbestos is present; and ix. Enclosures shall be inspected at least annually to ensure their integrity.

NYC-WTC 000104873