DEP letter reviewing WTC indoor dust cleaning scope of work,

NYC 9/11 Public Portal Document

approval by owner. After cleaning, red rosin construction paper will be applied to high traffic areas to protect carpets from soiling. Water extraction cleaning will not be conducted if it would cause damage to the carpet. f. Fabric covered fiimiture will be vacuumed and then cleaned with a water extractions cleaner after consultation with and if approved by owner. Water extraction cleaning will not be conducted if it would cause damage to the furniture. g- All surfaces including but not limited to floors, walls, curtains, fabric window treatments, upholstery and other materials that are not cleaned by wet methods (wet wiping and water extraction cleaning) will be HEPA vacuumed two times. Fabric covered furniture that is not cleaned by wet methods will be vacuumed using an appropriate brush attachment. h. Intake/discharge registers of HVAC systems (if present) will be removed/cleaned. The first foot of duct work will also be vacuumed; then the register will be reinstalled and covered with a layer of 6 mil polyethylene sheeting. 1. Window and room air conditioners will be vacuumed, wet wiped and removed from their housing to allow access to internal portions of the air conditioner. The internal portions of the air conditioner and housing will then be vacuumed. Filters will be vacuumed and reinstalled. Air conditioners will be reassembled and reinstalled after cleaning. j- Paperwork and books will be HEPA vacuumed. k. Electrical outlets will be vacuumed. 1. Appliances such as refrigerators and stoves will be cleaned and moved. The floor footprint of the appliances will be cleaned and the appliance will be reinstalled in their original positions. m. Refrigerator cooling tubes will be brushed and vacuumed. n. The first foot of all exhaust duct work (including stove, dryer and bathroom vents) where accessible, will be vacuumed. Exhaust fans will be vacuumed and wiped o. Closet floors will be vacuumed. P- Solid objects (electrical equipment, exercise equipment, etc.) will be wet wiped, moved to allow cleaning of the underlying surface and will be returned to their original location. q- Dishwasher toe plates will be removed and the floor beneath the appliance will be cleaned. r. Baseboard heaters will be cleaned. Protective covers on firmed radiant heaters and baseboard heaters will be removed to expose heat elements. Fins are to be brushed and vacuumed to remove dust. s. All cleaning equipment will be vacuumed and/or wet wiped after completion of the cleaning and before removal from the work area.

9. HEPA air filtration devices (AFDs) will run continuously during all cleaning activities, as appropriate given site conditions. AFDs shall be installed and operated to provide a minimum of one air change every 15 minutes.

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