NYC-WTC_000196112

NYC 9/11 Public Portal Document

Conclusions and Recommendations

Based upon the work performed by AmTrust, NYCHA staff and the EPA's and OSHA's published testing results, the Technical Service Department and the Employee Health & Safety Compliance Office found 250 Broadway to be safe for occupancy on September 17, 2001. The EPA's and OSHA's findings indicate that the dust and particulate in the air in lower Manhattan does not contain hazardous materials at levels of concern. However, in general dusts can cause respiratory symptoms and eye and throat irritation. Because dust will continue to remain in the air during the ensuing clean-up efforts following the World Trade Center disaster, Employee Health & Safety Compliance Office and Technical Services departments recommend the following course of action for the maintenance of 250 Broadway; v' Testing and Balancing of the HVAC System: Testing and balancing involves the testing, adjusting, and balancing of HVAC system components so that the entire system provides airflows that are in accordance with the design specifications. Typical components and system parameters tested include: • all supply, return, exhaust, and outdoor airflow rates • control settings and operation • air temperatures • fan speeds and power consumption • filter or collector resistance The typical test and balance is designed to accomplish three goals: verify and ensure the most effective system operation within the design specifications, identify and correct any problems, and ensure the safety of the system. A test and balance report should provide a complete record of the design, preliminary measurements, and final test data. The report should include any discrepancies between the test data and the design specifications, along with reasons for those discrepancies. Positively Pressurize the Building with the Minimum Amount of Outside Air: Keeping the building positively pressurized will reduce the infiltration of unfiltered air into the building. Weekly Visual Inspection of the HVAC System: Tech Services Staff will visually inspect air handling units, filters and supply ducts for damage and/or dust build-up. Maintain the Relative Humidity within the Building around 50%: Moist Air can help reduce odors and help prevent our respiratory tracts from getting dry. Z Integrate Dust Suppression Techniques into Building O&M: Mop lobby twice daily, power wash side walk weekly and install dust mats (sticky mats) at lobby elevator entrances. Indoor Air Quality (lAQ) Investigation: AmTrust must hire a Certified Industrial Hygienist to perform a complete lAQ Investigation of the Building. Subsequent monitoring will be based upon the finding of the intial investigation. Monitoring of EPA Testing Results: Tech Services will monitor the EPA's published findings: if the EPA has a positive finding at one of its monitoring stations near 250 Broadway, Tech Services will request that AmTrust test 250 Broadway for that contaminant.

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NYC-WTC_000196119