Guidance for completing ventilation system evaluation forms

NYC 9/11 Public Portal Document

Guidance for Ventilation System Evaluation Form Page 3 of7

Other information -

Indicate the level of visible particulate loading on the filter. Light - lightly visible accumulation. Moderate - obvious visible accumulation. Heavy - heavy accumulation that may result in filter panel disfiguration or filter bypass.

Indicate whether damaged interior acoustical duct lining is observed. If possible, note the location where the damage is observed.

Indicate obvious sources of filter bypass, e.g., improper size of filters, tracks, damaged or missing tracks, or other causes of poor fit in tracks.

General impression - this space is for the HVAC Evaluator’s general impression of whether or not cleaning is indicated based on the presence of WTC dust. The HVAC Evaluator should note any other comments that are deemed relevant to the determination of WTC dust or comments on conditions that would likely impact the scope or feasibility of cleaning.

2.2 Mechanical Exhaust System

Perform the most vigorous visual inspection possible. Minimum inspection equipment should include screwdrivers, a utility knife (for opening panels, diffusers, grilles, etc. that are painted or caulked in place), cordless drill, hole plugs, telescoping mirror, flashlight, and portable borescope. In addition, the HVAC Evaluator should attempt to penetrate visible dust to determine if a WTC layer is present.

When a ventilation system component is accessed for inspection, indicate whether or not surface dust/debris is present, and whether or not suspect WTC dust is present in the second and third columns, respectively.

Associated Mechanical Room - indicate if there is a mechanical room associated with the mechanical exhaust system, e.g., the exhaust fan unit is located in the mechanical room.

Exhaust air outlet, exhaust fan unit - please check for all components that apply. If a listed component is not part of the system, then indicate “not present” (NP) in the right-hand column. If the component is likely to be present, but it cannot be located, indicate “not found” (NF) in the right-hand column. If the listed component is present and is located, but is not accessible for inspection, indicate “inaccessible” (I) in the right-hand column.

Exhaust air distribution - Roughly estimate the total linear footage of mechanical exhaust air ducts associated with the mechanical exhaust system, and indicate the number of locations where the interior of the duct was accessed for inspection in the spaces provided. Also circle the type of material from which the duct is constructed (e.g., metal, fibrous glass lined metal, masonry, fibrous glass board, flex duct, wood). If more than one type of duct material is present, circle all that apply.

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