HVAC assessment and cleaning procedure guidelines, 2002

NYC 9/11 Public Portal Document

»< Assessment, Cleaning and Restoration of HVAC Systems - ACR 2002

cleaning. At minimum, such personnel should have an Assessment includes three steps: (1) Building Usage understanding of HVAC system design, and experience Classification: (2) HVAC Contamination Evaluation: and in using accepted indoor environmental sampling (3) Environmental Impact Assessment. practices, current industry HVAC cleaning procedures, and applicable industry standards. The HVAC Contamination Evaluation and the Environmental Impact Assessment must include a visual 3.5 Conditions Requiring Cleaning evaluation of representative sections of the HVAC components and the occupied spaces served by the HVAC system cleaning shall be performed when any of HVAC system. This evaluation serves to assess the following conditions are found in the cleanliness conditions within the HVAC system and the physical inspection. integrity of system components and surfaces. 3.5.1H\/ACSystefnGQntamination— Information collected from the Project Assessment should be used to define the scope of the cleaning and HVAC systems should be operated in a clean condition. restoration project, cleaning methods to be employed, If significant accumulations of contaminants or debris are the environmental engineering controls required for the visually observed within the HVAC system, then cleaning workspace, and any unique project requirements. is necessary. Likewise, if evidence of microbial growth is visually observed or confirmed by analytical methods, 4.1 Building Use Classification then cleaning is required. Classifying the type of building and its uses is an if the HVAC system discharges visible particulate into important part of Project Assessment. Cleaning the occupied space, or a significant contribution of methods, project specifications, environmental airborne particles from the HVAC system into the indoor engineering controls, and cleanliness verification ambient air is confirmed, then cleaning is necessary. methods may vary among different buildings. Building classifications are listed in sections 4.1.1 to 4.1.8. See the guideline to this standard for discussion of the Aggressive Particle Profiling procedure, which may be 4.1.1 Industrial used to confirm if non-visible contaminants are being introduced into the indoor environment via the HVAC Buildings classified as industnal use include any facility system. housing the manufacture, fabrication, processing, handling and storage of materials or products. 3.5.2 Compromised Performance 4.1.2 Residential Heat exchange coils, cooling coils, air flow control devices, filtration devices, and air-handling equipment Buildings classified as residential use include stand­ determined to have restrictions, blockages, or alone homes, apartment buildings, and condominiums contamination deposits that may cause system where people reside. performance inefficiencies, air flow degradation, or that may significantly affect the design intent of the HVAC 4.1.3 Light Commercial system, shall be cleaned. Buildings classified as light commercial use include 3.5.3 Indoor Air Quality Management space with a constant volume HVAC system up to, and including 10 tons cooling or equivalent heating capacity, Indoor air quality management plans that include or 4000 CFM nominal air flow, whichever is greater. preventative cleaning and maintenance are recommended to minimize recurring contamination 4.1.4 Commercial within HVAC systems. Special consideration should also be given to buildings or residences with sensitive Buildings classified as commercial use include space populations such as immune-compromised individuals, with an HVAC system of greater than 10 tons, or and specialized environments or buildings with sensitive equivalent heating capacity, or 4000 CFM nominal air building contents or critical processes. flow, whichever is greater.

4 Project Assessment 4.1.4.1 Restaurants

A Project Assessment must take place prior to The patron seating areas and employee workspaces commencing with cleaning work. The Project within restaurants are classified as commercial use. Kitchen exhaust systems designed to remove grease-

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