| Efficiency by Particle Size. These units shall be used as air recirculating units only. All outdoor air requirements shall be met by a separate central air handling system with the proper filtration, as required in Table 1 of §131.148(a) of this title. (C) General ventilation requirements. All rooms and areas in the facility shall have provision for positive ventilation. Fans serving exhaust systems shall be located at the discharge end and shall be conveniently accessible for service. Exhaust systems may be combined, unless otherwise noted, for efficient use of recovery devices required for energy conservation. The ventilation rates shown in Table 1of §131.148(a) of this title shall be used only as minimum requirements, since they do not preclude the use of higher rates that may be appropriate. (i) To reduce utility costs, facility design may utilize energy conserving procedures including recovery devices, variable air volume, load shedding, systems shutdown, or reduction of ventilation rates (when specifically permitted) in certain areas when unoccupied. In no case shall patient care be jeopardized. (ii) Mechanical systems shall be arranged to take advantage of outside air conditions by using an economizer cycle when appropriate to reduce heating and cooling systems loads. Innovative design that provides for additional energy conservation while meeting the intent of this section for acceptable patient care may be presented to the department for consideration. (iii) Fully ducted supply, return and exhaust air for HVAC systems shall be provided for all patient care areas, storage rooms, and where required for fire safety purposes. Combination systems, utilizing both ducts and plenums for movement of air in these areas, shall not be permitted. All ductwork access panels shall be labeled. (iv) The designed capacity of the HVAC systems shall be capable of providing the ranges of temperatures and humidities as shown in Table 1 of §131.148(a) of this title. Where no values are noted or indicated, the indoor design temperature in all other areas shall be between 68 and 75 degrees Fahrenheit with relative humidity of not less than 30%. (v) Each trauma room shall have temperature and humidity indicating devices mounted at eye level. (vi) Outside air intake locations. (I) Outside air intakes shall be located at least 25 feet from exhaust outlets of ventilating systems, combustion equipment stacks, medical-surgical vacuum system outlets, plumbing vents, or areas which may collect vehicular exhaust or other noxious fumes. (Prevailing winds and proximity to other structures may require other arrangements.) (II) Plumbing and vacuum vents that terminate 5 feet above the level of the top of the air intake may be located as close as 10 feet to the air intake. (III) The bottom of outside air intakes serving central systems shall be located as high as practical but at least 6 feet above ground level, or if installed above the roof, 3 feet above the roof level. (vii) Contaminated air exhaust outlets from areas (laboratory hoods, etc.) that exhaust contaminated air shall be above the roof and be arranged to exhaust upward unless the air has been treated by an appropriate means where sidewall exhaust will be allowed. (viii) All toilet exhaust ventilation shall be exhausted to the exterior. Exhaust systems may be combined, unless otherwise noted, for efficient use of recovery devices required for energy conservation. (ix) Directional air flow. Ventilation systems shall be designed and balanced to provide pressure relationships contained in Table 1 of §131.148(a) of this title. Provisions in Note 4 of Table 1 of §131.148(a) of this title shall be followed for the reductions and shut down of ventilation systems when a room is unoccupied. (x) Air distribution devices. Turbulence and other factors of air movement to minimize airborne particulate matter shall be considered in the design of air distribution devices. Where extraordinary procedures require special designs, the installation shall be reviewed on a case-by-case basis. (I) All supply diffusers grilles shall be located on the ceiling or on a wall within four inches from the ceiling. (II) Air supply for the treatment rooms/areas, exam rooms/areas, and trauma rooms/areas shall be from ceiling outlets near the center of the work area to efficiently control air movement. (III) A minimum of two return air inlets located diagonally opposite from one another and near floor level shall be provided. Bottoms of the wall mounted return air grilles in trauma and other anesthetizing locations shall be at least four inches above the floor. (xi) The air handling units (AHU) shall not be started or operated without the filters installed in place, including. This includes the 90% efficiency filters where required. This includes during construction operations. Ducts shall be cleaned thoroughly and throughout by a National Air Duct Cleaners Association (NADCA) certified air duct cleaning contractor when the air handling systems have been operating without the required filters in place. When ducts are determined to be dirty or dusty, the department shall require a written report assuring cleanliness of duct and clean air quality. (xii) When duct humidifiers are located upstream of the final filters, they shall be located at least 15 feet from the filters. Duct work with duct-mounted humidifiers shall be provided with a means of removing water accumulation. An adjustable high-limit humidistat shall be located downstream of the humidifier to reduce the potential of condensation inside the duct. All duct takeoffs shall be sufficiently downstream of the humidifier to ensure complete moisture absorption. Reservoir-type water spray or evaporative pan humidifiers shall not be used. (xiii) All air handling units shall be equipped with filters having efficiencies equal to, or greater than, those specified in Table 2 of §131.148(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 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 trauma rooms/areas, treatment rooms/areas, exam rooms/areas) shall be equipped with filters having efficiencies equal to, or greater than, those specified for patient care areas in Table 2 of §131.148(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 2 filter beds are required by Table 2 of §131.148(b) of this title, filter bed number one shall be located upstream of the air conditioning equipment, and filter bed number 2 shall be downstream of the supply air blowers, cooling and heating coils. (IV) Where only 1 filter bed is required by Table 2 of §131.148(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 facility 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) 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) 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. Cont'd... |
