Residential sampling protocol, World Trade Center, Oct 2001

NYC 9/11 Public Portal Document

[wtc resideritiai plan octis.wpd Pagejii]

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VII. Screening Levels/Data Interpretation: Screening levels and actions are outlined in Section XI of this proposal.

Data will be evaluated by local, state and federal public health agencies. Evaluations will include: 1) Indoor sample results will be evaluated on a residence-by- residence basis (for the individual occupants) 2) All indoor data will be evaluated to determine the extent of public health implications for residents near the WTC 3) All outdoor data will be evaluated to determine the extent of public health implications for the general public living near the WTC 4) The relationship between materials found in indoor and outdoor samples will be evaluated.

If results of testing show contamination/materials present at levels of concern, efforts should be made to reduce these levels and to take steps that eliminate transporting them indoors (e.g,. reduce contaminant track in by removing or changing shoes prior to entering residence, use HEPA filters on HVAC systems, keep windows closed).

VIII. Interference from existing bldg materials: It is anticipated that some of the contaminants/materials found in this sampling effort will be un-related to the WTC event. Attempts will be made during sample collection to note other possible sources of contaminants (Section IX, Sample Description Needs).

To better determine if contaminants/materials found are within area background levels, approximately ten residential units outside of the concentric circle zones will be selected testing (indoor air and surface dust, outdoor air and siuTace dust).

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