Fax forwarding DEP briefing materials for Mayor's meeting, March 2002

NYC 9/11 Public Portal Document ■rV - It ,

Friday 15 of Mar 2002, Mayor Office ->718 595 4544 Page 25 Of 29

.A cleaning system appropriate for ;i specific masonry material may not be appropriate for adjacent masonry mortar joints. Tli^remova'ilof paini-'staih'bn-mdrtar joints should be avoided if possible.

Reducing the strength of the removal agent and'or the pressure applied for removing the paint/stain can minimize ''clean spots" left on masonry.

Masonry surfaces should be tested with non-staining ph strip.s after remoA'als are completed in order to ensure that the substrate has been adequately neutralized. Neutralizing a surtace involves removing all chemical and/or cleaning agents from tire fabric. .A substrate that has not been neutralized can lead to subsequent damage of the historic fabric.

.Applied Paint (Signage) to Significant Interior Historic Fabric: If paint (signage) is applied to significant interior fabric (e.g. murals, mosaics, decorative metals) an experienced architectural and or art conservator should be consulted regarding any treatment or removal. It is possible to successfully remove applied overpaint from even the most decorati\e or fragile substrates.

Health, Safety, and Environmental Issues:

It is the responsibility of the Applicant to obtain all local, federal and .state permits prior to tbe commencement of work and adhere to all local, state and federal laws with respect to tbe application and disposal of potential hazardous waste materials.

Sources:

zAlC Ethics and Standards Committee. "AIC Code of Ethics and Guidelines for Practice. ' Revised August, 1994.

Grimmer. .Anne E. 'Dangers of Abrasive Cleaning to Historic Buildings." Preservation Brief .Number 6. Washington. DC: National Park Service. 1979.

New A’ork Landmarks Conservancy. Historic Building Facades: The Alantial for .Maintenance and Rehabilitation. New 'fork: John Wilev & Sons. Inc., 1997.

Weaver. .Manin E. "Removing Graffiti from Historic Masonry." Preservation Brief Number 38. Washington. DC: National Park Service. 199.5.

Mote: Naljonal Park Service Preservcuion Briefi. including those referenced in ihese performance standards, ore available on rhe Internet: keyword Preservation Briefs.

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