| (xii) Filtration requirements. All air handling units shall be equipped with filters having efficiencies equal to, or greater than, those specified in Table 2 of §135.56(b) of this title. Filter efficiencies shall be average dust spot efficiencies tested in accordance with American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE), Inc., Standard 52.2, 1999 edition, Method of Testing General Ventilation Air-Cleaning Devices for Removal Efficiency by Particle Size. All joints between filter segments, and between filter segments and the enclosing ductwork, shall have gaskets and seals to provide a positive seal against air leakage. Air handlers serving more than one room shall be considered as central air handlers. All documents published by ASHRAE as referenced in this section may be obtained by writing or calling the ASHRAE, Inc. at the following address or telephone number: ASHRAE, 1791 Tullie Circle, Northeast, Atlanta, Georgia 30329; telephone (404) 636-8400. (I) Filtration requirements for air handling units serving single rooms requiring asepsis control. Dedicated air handlers serving only one room where asepsis control is required, such as, but not limited to, operating rooms, special procedure rooms, and treatment rooms shall be equipped with filters having efficiencies equal to, or greater than, those specified for patient care areas in Table 2 of §135.56(b) of this title. (II) Filtration requirements for air handling units serving other single rooms. Dedicated air handlers serving all other single rooms shall be equipped with nominal filters installed at the return air system. (III) Location of multiple filters. Where two filter beds are required by Table 2 of §135.56(b) of this title, filter bed number one shall be located upstream of the air conditioning equipment, and filter bed number two shall be downstream of the supply air blowers, cooling and heating coils. (IV) Location of single filters. Where only one filter bed is required by Table 2 of §135.56(b) of this title, it shall be located upstream of the supply fan. Filter frames shall be durable and constructed to provide an airtight fit with the enclosing ductwork. (V) Pressure monitoring devices. A manometer or draft gauge shall be installed across each filter bed having a required efficiency of 75% or more, including laboratory hoods requiring high efficiency particulate air (HEPA) filters. The pressure monitoring device shall be mounted below the ceiling line within the ASC such that it can be observed by staff. (D) Thermal and acoustical insulation for air handling systems. Asbestos containing insulation materials shall not be used. (i) Thermal duct insulation. Air ducts and casings with outside surface temperature below the ambient dew point or temperature above 80 degrees Fahrenheit shall be provided with thermal insulation. (ii) Insulation in air plenums and ducts. When installed, linings in air ducts and equipment shall meet the Erosion Test Method described in Underwriters Laboratories (UL), Standard 181, relating to Factory-Made Duct Materials and Air Duct Connectors, April 4, 1996 edition. This document may be obtained from the Underwriters Laboratories, 333 Pfingsten Road, Northbrook, Illinois 60062-2096. (iii) Insulation flame spread and smoke developed ratings. Interior and exterior insulation, including finishes and adhesives on the exterior surfaces of ducts and equipment, shall have a flame spread rating of 25 or less and a smoke developed rating of 50 or less as required by NFPA 90A, Chapters 4 and 5 and as determined by an independent testing laboratory in accordance with NFPA 255, A Standard Method of Test of Surface Burning Characteristics of Building Materials, 2000 Edition. (iv) Linings and acoustical traps. Duct lining and acoustical traps exposed to air movement shall not be used in ducts serving critical care areas. This requirement shall not apply to mixing boxes and acoustical traps that have approved nonabrasive coverings over such linings. (v) Frangible insulation. Insulation of soft and spray-on types shall not be used where it is subject to air currents or mechanical erosion or where loose particles may create a maintenance problem or occupant discomfort. (vi) Existing duct linings. Internal linings shall not be used in ducts, terminal boxes, or other air system components supplying operating rooms and the postoperative recovery suite, unless terminal filters of at least 90% efficiency are installed downstream of linings. (E) Ventilation for anesthetizing locations. When anesthesia is administered, ventilation for anesthetizing locations, as defined in NFPA 99, §3-3, shall comply with NFPA 99, §13.4.1.2 and any specific ventilation requirements of clauses (i) - (iii) of this subparagraph. (i) Smoke removal systems for anesthetizing locations. Smoke removal systems shall be provided in all windowless anesthetizing locations in accordance with NFPA 99, §6.4.1.2. Supply and exhaust systems for windowless anesthetizing locations shall be arranged to automatically exhaust smoke and products of combustion, prevent recirculation of smoke originating within the surgical suite, and prevent the circulation of smoke entering the system intakes, without in either case interfering with the exhaust function of the system. (ii) Smoke removal systems for surgical suites. Smoke removal systems shall be provided in all surgical suites in accordance with NFPA 99, §6.4.1.3. (iii) Smoke exhaust grilles. Exhaust grilles for smoke evacuation systems shall be ceiling-mounted or wall-mounted within 12 inches of the ceiling. (F) Location of return and exhaust air devices. The bottoms of wall-mounted return and exhaust air openings shall be at least four inches above the floor. Return air openings located less than six inches above the floor shall be provided with nominal filters. All exhaust air openings and return air openings located higher than six inches but less than seven feet above the floor shall be protected with grilles or screens having openings through which a one-half inch sphere will not pass. (G) Ray protection. Ducts which penetrate construction intended for X-ray or other ray protection shall not impair the effectiveness of the protection. (H) Fire damper requirements. Fire dampers shall be located and installed in all ducts at the point of penetration of a required two-hour or higher fire-rated wall or floor in accordance with the requirements of NFPA 101, §18.5.2. (I) Smoke damper requirements. Smoke dampers shall be located and installed in accordance with the requirements of NFPA 101, §20.3.7.3, and NFPA 90A, Chapter 5. (i) Protection of ducts penetrating fire and smoke partitions. Combination fire and smoke leakage limiting dampers (Class II) shall be installed in accordance with manufacturer's instructions for all ducts penetrating one and two-hour rated fire and smoke partitions required by NFPA 101, §20.3.7, Subdivision of Building Space (not required in ASCs meeting the provisions of NFPA 101, §20.3.7.2, Exception Number 1). (ii) Fail-safe installation. Combination smoke and fire dampers shall close on activation of the fire alarm system by smoke detectors installed and located as required by National Fire Protection Association 72, National Fire Alarm Code, 2002 Edition (NFPA 72), Chapter 8; NFPA 90A, Chapter 6; and NFPA 101, §20.3.5; the fire sprinkler system; and upon loss of power. Smoke dampers shall not close by fan shutdown alone unless it is a part of an engineered smoke removal system. (iii) Interconnection of air handling fans and smoke dampers. Air handling fans and smoke damper controls may be interconnected so that closing of smoke dampers will not damage the ducts. (iv) Frangible devices. Use of frangible devices for shutting smoke dampers is not permitted. (J) Acceptable damper assemblies. Only fire damper and smoke damper assemblies integral with sleeves and listed for the intended purpose shall be acceptable. (K) Duct access doors. Unobstructed access to duct openings in accordance with NFPA 90A, §4.3, shall be provided in ducts within reach and sight of every fire damper, smoke damper and smoke detector. Each opening shall be protected by an internally insulated door which shall be labeled externally to indicate the fire protection device located within. (L) Restarting controls. Controls for restarting fans may be installed for convenient fire department use to assist in evacuation of smoke after a fire is controlled, provided that provisions are made to avoid possible damage to the system because of closed dampers. To accomplish this, smoke dampers shall be equipped with remote control devices. Cont'd... |
