vided by the total electric energy input during the same period, in watt-hours. Heat Trap means a device coupled to the inlet and outlet of a water heater that effectively restricts the natural tendency of hot water to rise in the vertical pipe during periods of standby. Humidistat means an automatic control device responsive to changes in humidity. Illuminance means the density of the luminous flux incident on a surface. It is the quotient of the luminous flux multiplied by the area of the surface when the latter is uniformly illuminated. (See also Footcandle.) Industrial Process means any manufacturing or other process whose energy requirements are not primarily intended to contribute to the heating, cooling, lighting, ventilation, or service hot water energy load requirements of the building. Infiltration means the uncontrolled inward air leakage through cracks and crevices in any building element and around windows and doors of a building. Insolation means the rate of solar energy incident on a unit area with a given orientation. Integrated Part-Load Value means a single number figure of merit for airconditioning and heat pump equipment based on weighted operation at a set of less than full capacities for the equipment. the Lighting Power Budget means lighting power, in watts, allowed for an interior or exterior area or activity. Lighting Power Control Credit means the amount of interior connected lighting power which may be added to the Interior Lighting Power Allowance for lights in a space which is turned off or dimmed by automatic control devices. Lumen means SI unit of luminous flux. Radiometrically, it is determined from the radiant power. Photometrically, it is the luminous flux emitted within a unit solid angle (one steradian) by a point source having a uniform luminous intensity of one candela. Lumen Maintenance Control means a device that senses the illumination level and causes an increase/decrease of illuminance to maintain a preset illumination level. Luminaire means a complete lighting unit consisting of a lamp or lamps together with the parts designed to distribute the light, to position and protect the lamps, and to connect the lamps to the power supply. Luminaire Efficiency means the ratio of luminous flux (lumens) emitted by a luminaire to that emitted by the lamp or lamps used therein. Manual (Non-Automatic) means action requiring personal intervention for its control. As applied to an electric controller, non-automatic control does not necessarily imply a manual controller, but only that personal intervention is necessary. (See Automatic.) Non-Depletable Energy Sources means sources of energy, excluding minerals, derived from incoming solar radiation; thermal chemical or electrical energy derived directly from conversion of incident solar radiation; wind, waves and tides, lake, or pond thermal differences; and energy derived from the internal heat of the earth. Occupancy Sensor means a device that detects the presence or absence of people within an area and causes lighting, equipment, and/or appliances to be adjusted accordingly. Opaque Areas means all exposed areas of a building envelope which enclose conditioned space, except fenestration areas and building service openings, such as vents, grilles, and pipes. Orientation means the directional placement of a building on a building site with reference to the building's longest horizontal axis, or, if none, with reference to the designated main entrance. Outdoor (Outside) Air means air taken from the exterior of the building that has not been previously circulated through the building. (See also Ventilating Air.) Ozone Depletion Factor means a relative measure of the potency of chemicals in depleting stratospheric ozone. The ozone depletion factor potential depends upon the chlorine and the bromine content and atmospheric lifetime of the chemical. The depletion factor potentials are normalized such that the factor for CFC-11 is set equal to unity and the factors for the other chemicals indicate their potential relative to CFC-11. Packaged Terminal Air-Conditioner means a factory-selected wall sleeve and separate unencased combination of heating and cooling components, assemblies or sections, intended for mounting through the wall to serve a single room or zone. It includes heating capability by hot water, steam, or electricity. Packaged Terminal Heat Pump means a PTAC capable of using the refrigeration system in a reverse cycle or heat pump mode to provide heat. Piping means a system for conveying fluids, including pipes, valves, strainers, and fittings. Plenum means an enclosure that is part of the air handling system and is distinguished by having a very low air velocity. A plenum often is formed in part or in total by portions of the building. Power means, in connection with machines, the time rate of doing work; in connection with the transmission of energy of all types, the rate at which energy is transmitted; in inch-pound units, is measured in watts (W) or British thermal units per hour (Btu/h). Power Factor means the ratio of total watts to the root-mean-square (RMS) volt amperes. Prescribed Assumption means a fixed value of an input to the standard calculation procedure. Process Energy means energy consumed in support of a manufacturing, industrial, or commercial process, other than the maintenance of comfort and amenities for the occupants of a building. Process Load means the calculated or measured time-integrated load on a building resulting from the consumption or release of process energy. Proposed Design means a prospective design for a building that is to be evaluated for compliance. Prototype Building means a generic building design of the same size and occupancy type as the proposed design, which complies with the prescriptive requirements of the standards and has prescribed assumptions used to generate the energy budget concerning shape, orientation, HVAC, and other system designs. Public Facility Restroom means a restroom used by the transient public. Radiant Comfort Heating means a system in which temperatures of room surfaces are adjusted to control the rate of heat loss by radiation from occupants. Readily Accessible means capable of being reached quickly for operation, renewal, or inspections, without requiring those to whom ready access is requisite to climb over or remove obstacles or to resort to portable ladders, chairs, and so on. (See also Accessible.) Recooling means lowering the temperature of air that has been previously heated by a heating system. Recovered Energy means energy utilized which would otherwise be wasted (not contributing to a desired end use) from an energy utilization system. Reference Building means a specific building design that has the same form, orientation and basic systems as the proposed design and meets all the criteria of the prescriptive compliance method. Reflectance means the ratio of the light reflected by a surface to the light incident upon it. Reheating means raising the temperature of air that has been previously cooled either by a refrigeration or an economizer system. Reset means adjustment of the controller set point to a higher or lower value automatically or manually. Residential means any structure which is constructed and developed for residential occupancy. Retail Establishments means, for the purpose of determining lighting power limit, buildings, the primary functions of which are designed to be: (1) Type A-Jewelry Merchandising, where the minute display and examination of merchandise is critical. (2) Type B-Fine Merchandising: Fine apparel and accessories, china, crystal and silver, art galleries, etc., where the detailed display and examination of merchandise is important. (3) Type C-Mass Merchandising, where focused display and detailed examination of merchandise is important. (4) Type D-General Merchandising: General apparel, variety, stationery, books, sporting goods, hobby, cameras, gift, luggage, etc., where general display and examination of merchandise are adequate. (5) Type E-Food & Miscellaneous: Bakeries, hardware and housewares, grocery, appliances and furniture, etc., where appetizing appearance is important. (6) Type F-Service Establishments, where functional performance is important. Roof means those portions of the building envelope including all opaque surfaces, fenestration, doors, and hatches which are above conditioned space and which are horizontal or tilted at less than 45° from horizontal. (See also Walls.) Room Air Conditioner means an encased assembly designed as a unit to be mounted in a window or through a wall, or as a console. It is designed primarily to provide free delivery of conditioned air to an enclosed space, room, or zone. It includes a prime source of refrigeration for cooling and dehumidification and means for circulating and cleaning air, and may also include means for ventilating and heating. Ratio Seasonal Energy Efficiency means the total cooling output of an air conditioner during its normal annual usage period for cooling, in Btu/h, divided by the total electric energy input during the same period, in watthours, as determined by 10 CFR, part 430. Service Systems means all energyusing or distributing components in a building that are operated to support the occupant or process functions housed therein, including HVAC, service water heating, illumination, transportation, cooking or food preparation, laundering or similar functions. Service Water Heating means the supply of hot water for purposes other than comfort heating and process requirements. Service Water Heating Demand means the maximum design rate of water withdrawal from a service water heating system in a designated period of time (usually an hour or a day). Shading Coefficient means the ratio of solar heat gain through fenestration, with or without integral shading devices, to that occurring through unshaded 1⁄2 inch thick clear, double strength glass. Shell Building means a building for which the envelope is designed and/or constructed prior to knowing the occupancy type. (See also Speculative Building.) Speculative Building means a building for which the envelope is designed and/ or constructed prior to the design of the lighting and/or HVAC systems. A speculative building differs from a shell building in that the intended occupancy is known for the speculative building. (See also Shell Building.) Standard Calculation Procedure means an energy simulation model, and a set of input assumptions, that produce estimates of annual energy consumption for heating, cooling, ventilation, lighting, and other uses and that account for the dynamic thermal performance of the building. System means a combination of equipment and/or controls, accessories, interconnecting means, and terminal elements by which energy is transformed so as to perform a specific function, such as HVAC, service water heating, or illumination. Tandem Wiring means pairs of luminaires operating with one lamp in each luminaire powered from a single two-lamp ballast contained in the other luminaire. Task Lighting means lighting that provides illumination for specific visual functions and is directed to a specific surface or area. Task Location means an area of the space where significant visual functions are performed and where lighting is required above and beyond that required for general ambient use. Terminal Element means a device by which the transformed energy from a system is finally delivered; i.e., registers, diffusers, lighting fixtures, faucets, etc. Thermal Conductance means the constant time rate of heat flow through unit area of a body induced by a unit temperature difference between the surfaces, Btu/ft2•h•°F or Btu/h•°F. It is reciprocal of thermal resistance. (See Thermal Resistance.) Thermal Mass means materials with mass heat capacity and surface area capable of affecting building loads by storing and releasing heat as the interior and/or exterior temperature and radiant conditions fluctuate. (See also Wall Heat Capacity.) Thermal Mass Wall Insulation Position: (1) Exterior Insulation Position means a wall having all or nearly all of its mass exposed to the room air with the insulation on the exterior of that mass. (2) Integral Insulation Position means a wall having mass exposed to both room and outside air, with substantially equal amounts of mass on the inside and outside of the insulation layer. (3) Interior Insulation Position means a wall not meeting either of the above definitions, particularly a wall having most of its mass external to an insulation layer. Thermal Resistance means the reciprocal thermal conductance; 1/C as well as 1/h, 1/U, hoft2°F/Btu. Thermal Transmittance means the overall coefficient of heat transfer from air to air. It is the time rate of heat flow per unit area under steady conditions from the fluid on the warm side of the barrier to the fluid on the cold side, per unit temperature dif ference between the two fluids, Btu/ hoft2°F. Thermal Transmittance, Overall means the gross overall (area weighted average) coefficient of heat transfer from air to air for a gross area of the building envelope, Btu/h ft2°F. The thermal transmittance (U°) value applies to the combined effect of the time rate of heat flows through the various parallel paths, such as windows, doors, and opaque construction areas, comprising the gross area of one or more building envelope components, such as walls, floors, or roof/ceiling. Thermostat means an automatic control device responsive to temperature. Unconditioned Space means a volume within a building that is not designed to be directly or indirectly heated and/ or cooled. (See Conditioned Space.) Unit Power Density means the floor area designated for a specific occupancy, function, or activity expressed in W/ft2. Unitary Cooling Equipment means one or more factory-made assemblies which normally include an evaporator or cooling coil, a compressor and condenser combination, and may include a heating function as well. Unitary Heat Pump means one or more factory-made assemblies which normally include an indoor conditioning coil, compressor(s) and outdoor coil or refrigerant-to-water heat exchanger, including means to provide both heating and cooling functions. Unlisted Space means the difference in area between the gross lighted area and the sum of all listed spaces. Variable Air Volume (VAV) HVAC System means HVAC systems that control the dry-bulb temperature within a space by varying the volume of supply air to the space. Ventilation means the process of supplying or removing air by natural or mechanical means to or from any space. Such air may or may not have been conditioned. Ventilation Air means that portion of supply air which comes from outside (outdoors) plus any recirculated air that has been treated to maintain the desired quality of air within a designated space. (See also Outdoor Air.) Visual Task means those details and objects that must be seen for the per means an energy consumption goal or goals to be met without specification of the method, materials, and processes to be employed in achieving that goal or goals, but including statements of the requirements, criteria and evaluation methods to be used, and any necessary commentary. Walls means those portions of the building envelope enclosing conditioned space including all opaque surfaces, fenestration and doors, which are vertical or tilted at an angle of 45° from horizontal or greater. (See also Roof.) Wall Heat Capacity means the sum of the products of the mass of each individual material in the wall per unit area of wall surface times its individual specific heat, Btu/F. (See Thermal Mass.) Watt means a unit of power. One watt is produced when one ampere, flows at an amp of one volt (unity power factor). (See also Power.) Zone means a space or group of spaces within a building with heating, cooling, and/or lighting requirements sufficiently similar so that desired conditions can be maintained throughout by a single controlling device. (b) For definitions not found in paragraph (a) of this section, the 1986 edition of "Terminology of Heating and Ventilation, Air-Conditioning, and Refrigeration" as published by the American Society of Heating, Refrigeration, and Air-Conditioning Engineers, Inc. (ASHRAE) shall apply to these standards. (c) For purposes of this subpart, the acronyms and abbreviations shall have the following meanings: A-Total Building Floor Area. Awall, roof, etc.-Area of a Specific Building component. AAMA-American Aluminum Manufac turers Association. ACP-Alternative Component Package. AF-Area Factor. AFUE-Annual Fuel Utilization Efficiency. AHAM-Association of Home Appliance Manufacturers. ALP—Adjusted Lighting Power. CDD65 Cooling Degree-Days Base 65 °F. CDH-Cooling Degree-Hours. CDH80 Cooling Degree-Hours Base 80 CFR Code of Federal Regulations. EPD-Equipment Power Density. GLA-Gross Lighted Building Area. HDD-Heating Degree-Days. HDD50-Heating Degree-Days Base 50 °F. HDD65-Heating Degree-Days Base 65 °F. HI-Hydronics Institute. HID-High Intensity Discharge. HSPF-Heating System Performance HVAC Heating, Ventilating and Air Conditioning. IEEE Institute of Electrical and Electronics Engineers, Inc. IES-Illuminating Engineering Society of North America. ILPA-Interior Lighting Power Allow ance. |