NYC-WTC_000195194

NYC 9/11 Public Portal Document

w Baseboard heating components, including the hydronic finned radiation systems, were cleaned. The protective covers were removed to expose the heating elements. The fins were then vacuumed and brushed simultaneously to remove dust. The space located under the heating element was vacuumed. The protective covers were reattached.

Cleaning of Refrigerators. Dishwashers and Stoves (including exhaust fans). Prior to cleaning refrigerators, the appliance was unplugged and checked for food contents. If present, food was removed, bagged and disposed. The coils, underbody, compressor compartment, and back of each refrigerator was cleaned. Dust from the cooling coils was cleaned by elevating the appliance and simultaneously using vacuums and specialized brushes. Upon completing these activities the floor area where the refrigerator had been located was cleaned. Prior to cleaning, each stove unit was disconnected from its electric receptacle and gas line. Old exhaust fan lights and filters were removed and replaced. The first foot of the exhaust duct was vacuumed. The stove hood was vacuumed. Prior to cleaning dishwashers, the toe plate was removed and dust was vacuumed from under the appliance. After cleaning, all appliances were staged on plastic for subsequent removal by the owner, who had decided to replace them:

Pre-Cleaning and Post-Cleaning Sampling. Pre-cleaning and post-cleaning sampling was performed to measure levels of COPC. Sampling data was reviewed and a decision regarding the need for additional cleaning was made. Wipe samples were collected from solid surfaces, both vertical and horizontal. A micro vacuum technique was used on sofas, mattresses, and porous materials. All sampling was conducted in accordance with the Quality Assurance Project Plan w (QAPP) contained within Attachment G, Sampling and Analysis Plan. w 2.7 Cleaning of Commercial Units, Common Areas and Basement

The cleaning of each commercial unit was accomplished using the vacuum equipment type prescribed by the designated test, as presented in Attachment H, Synopsis of Cleaning by -« Building Area and Fact Sheets. Management of waste was accomplished as the cleaning activities occurred. The sequence of procedures for vacuuming, wet wiping, waste management, and pre-cleaning and post-cleaning sampling mirrored the procedures used in the residential units. Cleaning of the HVAC systems and carpets presented the only significant differences from the procedures used to clean the residential units. A discussion of the procedures used to clean the HVAC systems and carpets in the commercial units and the procedures used to clean the common areas and the basement follows.

HVAC Systems The Chiropractor’s Office is located in the north end of the building at the Liberty Street address. It contains four patient rooms and an administrative section with a waiting room and a half bath facility. The air conditioning system in the unit is suspended from the third floor deck above a suspended acoustical tiled ceiling, located in the south end of the office space. It utilizes a W common closed return to convey air to the blower cabinet. The supply trunk runs northward, supplying air to the balance of the rental space through supply diffuser grills. The system's condenser/compressor unit is located on the building's atrium roof area at the second floor elevation.

The Mattress Store is located in the north end of the building at the Liberty Street address. Space 19

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