[Code of Federal Regulations]
[Title 10, Volume 3]
[Revised as of January 1, 2001]
From the U.S. Government Printing Office via GPO Access
[CITE: 10CFR435.99]

[Page 396-405]
 
                            TITLE 10--ENERGY
 
                    CHAPTER II--DEPARTMENT OF ENERGY
 
PART 435--ENERGY CONSERVATION VOLUNTARY PERFORMANCE STANDARDS FOR NEW BUILDINGS; MANDATORY FOR FEDERAL BUILDINGS--Table of Contents
 
Subpart A--Voluntary Performance Standards for New Commercial and Multi-
 Family High Rise Residential Buildings; Mandatory for Federal Buildings
 
Sec. 435.99  General definitions and acronyms.

    (a) For the purpose of this subpart:
    Accessible (as applied to equipment) means admitting close approach; 
not guarded by locked doors, elevation, or other effective means. (See 
also Readily Accessible.)
    Adjusted Lighting Power means lighting power, ascribed to a 
luminaire(s), that has been reduced by deducting a lighting power 
control credit based on use of an automatic control device.
    Annual Fuel Utilization Efficiency means the ratio of annual output 
energy to annual input energy that includes any non-heating season pilot 
input loss.
    Air Conditioning, Comfort means treating air to control its 
temperature, relative humidity, cleanliness, and distribution to meet 
the comfort requirements of the occupants of the conditioned space. Some 
air conditioners may not accomplish all of these controls.
    Ambient Lighting means lighting that produces general illumination 
throughout an area.
    Area Factor means a multiplying factor that adjusts the base unit 
power density (UPD) for spaces of various sizes to account for the 
impact of room configuration on lighting power utilization.
    Automatic means a self-acting, operating by its own mechanism, when 
actuated by some impersonal influence, such as, a change in current 
strength, pressure, temperature or mechanical configuration. (See also 
Manual.)
    Ballast means a device used with an electric-discharge lamp to 
obtain the necessary circuit conditions (voltage, current, and wave 
form) for starting and operating.
    Ballast Efficacy Factor--Fluorescent means the ratio of the relative 
light output to the power input in watts, at specified test conditions, 
expressed as a percent.
    Ballast Factor means the ratio of a commercial ballast lamp lumens 
to a reference ballast lamp lumens, used to correct the lamp lumen 
output from rated to actual.
    Boiler Capacity means the rated heat output in Btu/h of the boiler, 
at the design inlet and outlet conditions and rated fuel/energy input.
    British Thermal Unit means approximately the amount of heat required 
to raise the temperature of one pound of water from 59  deg.F to 60 
deg.F.
    Building means any new structure to be constructed that includes 
provision for a heating or cooling system, or both, or for a hot water 
system.
    Building Code means a legal instrument which is in effect in a state 
or unit of general purpose local government, the provisions of which 
must be adhered to if a building is to be considered to be in 
conformance with law and suitable for occupancy and use.
    Building Design means the architectural and engineering drawings and 
specifications used for the construction of a new building.
    Building Energy Cost means the computed annual energy cost of all 
purchased energy for the building, calculated using the methods of 
section 435.111 of these standards.

[[Page 397]]

    Building Envelope means the elements of a building that enclose 
conditioned spaces through which thermal energy may be transferred to or 
from the exterior or to or from unconditioned spaces.
    Building Type means the classification of a building by usage. In 
this regulation the following classifications of buildings are defined 
by these uses:
    (1) Assembly means a building or structure for the gathering 
together of persons, such as auditoriums, churches, dance halls, 
gymnasiums, theaters, museums, passenger depots, sports facilities, and 
public assembly halls.
    (2) Health and Institutional means a building or structure for the 
purpose of providing medical treatment, confinement or care, and 
sleeping facilities such as hospitals, sanitariums, clinics, orphanages, 
nursing homes, mental institutions, reformatories, jails, and prisons.
    (3) Hotel/Motel means a building or structure for transient 
occupancy, such as resorts, hotels, motels, barracks, and dormitories.
    (4) Multi-Family means a building or structure containing three or 
more dwelling units. (See Dwelling Units, and Multi-Family Dwelling.)
    (5) Office (Business) means a building or structure for office, 
professional, or service type transactions, such as medical offices, 
banks, libraries, and business offices, including governmental office 
buildings.
    (6) Restaurant means a building or a structure for the consumption 
of food or drink, including fast food, coffee shops, cafeterias, bars, 
and restaurants.
    (7) Retail (Mercantile) means a building or a structure for the 
display and sale (wholesale or retail) of merchandise, such as shopping 
malls, food markets, auto dealerships, department stores, and specialty 
shops. (See also Retail Establishments.)
    (8) School (Educational) means a building or structure for the 
purpose of instruction, such as schools, colleges, universities, and 
academies.
    (9) Warehouse (Storage) means a building or structure for storage, 
such as aircraft hangers, garages, warehouses, storage buildings, and 
freight depots.
    Check Metering means measurement instrumentation for the 
supplementary monitoring of energy (electric, gas, oil, etc.) 
consumption, in addition to the revenue metering furnished by the 
utility, to isolate the various categories of energy use to permit 
conservation and control.
    Coefficient of Performance--Cooling means the ratio of the rate of 
heat removal to the rate of energy input in consistent units, for a 
complete cooling system or factory assembled equipment, as tested under 
a nationally recognized standard or designated operating conditions.
    Coefficient of Performance, Heat Pump--Heating means the ratio of 
the rate of heat delivered to the rate of energy input, in consistent 
units, for a complete heat pump system under designated operating 
conditions. When checking compliance with the heat pump equipment COP's 
listed in the tables in section 435.108.
    Combined Thermal Transmittance Values (See Thermal Transmittance, 
Overall.)
    Commercial Building means a building other than a residential 
building, including any building developed for industrial or public 
purposes.
    Conditioned Floor Area means the area of the conditioned space 
measured at floor level from the interior surfaces of the walls.
    Conditioned Space means a volume within a building that is designed 
to be heated and/or cooled, directly or indirectly.
    Connected Lighting Power means the power required to energize 
luminaires and lamps installed and connected to the building electrical 
service, in watts.
    Control Loop, Local means a control system consisting of a sensor, a 
controller, and a controlled device.
    Cooled Space means an enclosed area within a building that has a 
refrigeration system whose sensible capacity exceeds 5 Btu/hft\2\ or is 
capable of maintaining space dry bulb temperatures of 90  deg.F or less 
at design cooling conditions.
    Daylight Sensing Control means a device that automatically regulates 
the power input to electric lighting near

[[Page 398]]

the fenestration to maintain the desired workplace illumination, thus 
taking advantage of direct or indirect sunlight.
    Dead Band (Dead Zone) means the range of values within which an 
input variable can be varied without initiating any noticeable change in 
the output variable.
    Default Assumption means the value of an input used in a calculation 
procedure when a value is not entered by the designer.
    Degree-Day means a unit, based upon temperature difference and time, 
used in estimating fuel consumption and specifying nominal heating load 
of building in winter. For any day, when the mean temperature is less 
than a reference temperature, typically 65  deg.F, there are as many 
Degree-Days as Fahrenheit degrees difference in temperature between the 
mean temperature for the day and the reference temperature.
    Degree Day, Cooling means a unit, based upon temperature difference 
and time, used in estimating cooling energy consumption. For any one 
day, when the mean temperature is more than a reference temperature, 
typically 65  deg.F, there are as many Degree Days as degrees Fahrenheit 
temperature difference between the mean temperature for the day and the 
reference temperature. Annual Cooling Degree Days (CDD) are the sum of 
the degree days over a calendar year.
    Degree Day, Heating means a unit, based upon temperature difference 
and time, used in estimating heating energy consumption. For any one 
day, when the mean temperature is less than a reference temperature, 
typically 65  deg.F, there are as many Degree Days as degrees Fahrenheit 
temperature difference between the mean temperature for the day and the 
reference temperature. Annual Heating Degree Days (HDD) are the sum of 
the degree days over a calendar year.
    Demand (Electric) means the rate at which electric energy is 
delivered to or by a system, part of a system, or a piece of equipment; 
expressed in kilowatts, kilovoltamperes; or other suitable units at a 
given instant or averaged over any designated period.
    Design Conditions means the exterior and interior environmental 
parameters specified for air conditioning and electrical design for a 
facility.
    Design Energy Consumption means the computed annual energy usage of 
a proposed building design.
    Design Energy Costs means the computed annual energy expenditures of 
a proposed building design.
    Dwelling Unit means a single housekeeping unit comprised of one or 
more rooms providing complete, independent living facilities for one or 
more persons including permanent provisions for living, sleeping, 
eating, cooking, and sanitation.
    Economizer, Air means a ducting arrangement and automatic control 
system that allows a cooling supply fan system to supply outside air to 
reduce or eliminate the need for mechanical refrigeration during mild or 
cold weather.
    Economizer, Water means a system by which the supply air of a 
cooling system is cooled directly and/or indirectly by evaporation of 
water, or by other appropriate fluid, in order to reduce or eliminate 
the need for mechanical refrigeration.
    Efficiency, HVAC System means the ratio of the useful energy output 
(at the point of use) to the energy input in consistent units for a 
designated time period, expressed in percent.
    Emergency System (Back Up System) means a system which exists for 
the purpose of operating in the event of failure of a primary system.
    Energy means the capability for doing work; having several forms 
that may be transformed from one to another, such as thermal (heat), 
mechanical (work), electrical, and chemical.
    Energy Cost means the annual cost of energy by unit and type of 
energy.
    Energy Cost Budget means the maximum allowable computed annual 
energy expenditure for a proposed building.
    Energy Efficiency Ratio means the ratio of net equipment cooling 
capacity in Btu/h to total rate of electric input in watts under 
designated operating conditions. When consistent units are used, this 
ratio becomes equal to COP. (See also Coefficient of Performance.)

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    Energy Management System means a control system designed to monitor 
the environment and the use of energy in a facility and to adjust the 
parameters of local control loops to conserve energy while maintaining a 
suitable environment.
    Energy, Recovered (See Recovered Energy.)
    Enthalpy means a thermodynamic property of a substance defined as 
the sum of its internal energy plus the quantity PV/J, where P=pressure 
of the substance, V=its volume, and J=the mechanical equivalent of heat; 
formerly called total heat and heat content.
    Exterior Envelope (See Building Envelope.)
    Fenestration means any light-transmitting section in a building wall 
or roof. The fenestration includes glazing material, which may be glass 
or plastic; framing, mullions, muntins, and dividers; external shading 
devices; internal shading devices, and integral (between-glass) shading 
devices.
    Federal Agency means any department, agency, corporation, or other 
entity or instrumentality of the executive branch of the Federal 
Government, including the United States Postal Service, the Federal 
National Mortgage Association, and the Federal Home Loan Mortgage 
Corporation.
    Federal Building means any building to be constructed by, or for the 
use of, any Federal Agency which is not legally subject to State or 
local building codes or similar requirements.
    Footcandle means the unit of illuminance on a surface one square 
foot in area on which there is a uniformly distributed flux of one 
lumen, or the illuminance produced on a surface all points of which are 
at a distance of one foot from a directionally uniform point source of 
one candela.
    General Lighting means lighting designed to provide illumination 
throughout an area, exclusive of any provision for special local 
requirements.
    Gross Floor Area means the sum of the areas of the several floors of 
the building, including basements, mezzanine and intermediate-floored 
tiers and penthouses of headroom height, measured from the exterior 
faces of exterior walls or from the centerline of walls separating 
buildings, but excluding covered walkways, open roofed-over areas, 
porches and similar spaces, pipe trenches, exterior terraces or steps, 
chimneys, roof overhangs, and similar features.
    Gross Lighted Area means the sum of the total lighted areas of a 
building measured from the inside of the perimeter walls, for each floor 
of the building.
    Gross Roof Area means the total surface of the roof assembly exposed 
to the outside air, including all roof/ceiling and skylight components 
through which heat may flow between indoor and outdoor environments, 
excluding service openings.
    Gross Exterior Wall Area means the total surface of the wall 
assembly exposed to the outside air and enclosing a heated or cooled 
space consisting of opaque surfaces, including between floor spandrels, 
peripheral edges of flooring and window areas including sash and door 
areas but excluding vents, grilles, and pipes.
    HVAC System means the equipment distribution network and terminals 
that provide either collectively or individually the processes of 
heating, ventilating, and/or air conditioning to a building.
    HVAC System Efficiency (See Efficiency, HVAC System.)
    Heat means the form of energy that is transferred by virtue of a 
temperature difference or a change in state of a material.
    Heat Capacity means the amount of heat necessary to raise the 
temperature of a given mass one degree. Numerically the mass multiplied 
by the specific heat.
    Heated Space means a volume within a building which is provided with 
a positive supply of thermal energy by a system whose output capacity 
either exceeds 10 Btu/hft \2\ or is capable of maintaining a space dry-
bulb temperature of 50  deg.F or more at design building conditions.
    Heating System Performance Factor means the total heating output of 
a heat pump during its normal annual usage period for heating, in Btu, 
divided by the total electric energy input during the same period, in 
watt-hours.

[[Page 400]]

    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.
    Lighting Power Budget means the 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.)
    Marked Rating means the design load operating conditions of a device 
as shown by the manufacturer on the nameplate or otherwise marked on the 
device.
    Minimum Life Cycle Cost Methodology means the methodology specified 
in subpart A of 10 CFR part 436.
    Motor Efficiency, Nominal means the median efficiency occurring in a 
population of motors of the same manufacturer and rating.
    Multi-Family High Rise Residential Building means a residential 
building containing three or more dwelling units and is designed to be 3 
or more stories above grade.
    Multi-Family Low Rise Residential Building means a residential 
building containing three or more dwelling units and is designed not to 
exceed two stories above grade.
    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

[[Page 401]]

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 Adjustment Factor means a modifying factor that adjusts the 
effective connected lighting power of a space to account for the use of 
energy conserving lighting control devices.
    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.

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    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 deg. 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.
    Seasonal Energy Efficiency Ratio 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 watt-hours, as determined by 10 CFR, part 430.
    Service Systems means all energy-using 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 \1/8\ 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

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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/ft\2\h  deg.F or Btu/h  deg.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, hft\2\  deg.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 difference between the two 
fluids, Btu/hft\2\  deg.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/hft\2\  deg.F. The thermal 
transmittance (U deg.) 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/ft\2\.
    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.)

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    Visual Task means those details and objects that must be seen for 
the performance of a given activity, and includes the immediate 
background of the details or objects.
    Voluntary Performance Standards 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  deg. 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:

Ao--Total Building Floor Area.
Awall,roof,etc.--Area of a Specific Building component.
AAMA--American Aluminum Manufacturers Association.
ACP--Alternative Component Package.
AF--Area Factor.
AFUE--Annual Fuel Utilization Efficiency.
AHAM--Association of Home Appliance Manufacturers.
ALP--Adjusted Lighting Power.
ANSI--American National Standards Institute.
ARI--Air-Conditioning and Refrigeration Institute.
ASHRAE--American Society of Heating, Refrigeration and Air Conditioning 
    Engineers, Inc.
ASME--American Society of Mechanical Engineers.
ASTM--American Society for Testing and Materials.
Btu--British Thermal Unit.
Btu/h--British Thermal Units Per Hour.
C--Thermal Conductance.
Cc--Cooling Criteria.
CDD--Cooling Degree-Days.
CDD50--Cooling Degree-Days Base 50  deg.F.
CDD65--Cooling Degree-Days Base 65  deg.F.
CDH--Cooling Degree-Hours.
CDH80--Cooling Degree-Hours Base 80  deg.F.
CEEU--Cost Equivalent Energy Units.
cfm--Cubic Feet Per Minute.
CFR--Code of Federal Regulations.
CLP--Connected Lighting Power.
COP--Coefficient of Performance.
CU--Coefficient of Utilization.
DOE--U.S. Department of Energy.
DR--Average Daily Temperature Range for Warmest Month.
EER--Energy Efficiency Ratio.
ELPA--Exterior Lighting Power Allowance.
EPD--Equipment Power Density.
o F--Degrees-Fahrenheit
GLA--Gross Lighted Building Area.
HC--Heat Capacity.
HDD--Heating Degree-Days.
HDD50--Heating Degree-Days Base 50  deg.F.
HDD65--Heating Degree-Days Base 65  deg.F.
HI--Hydronics Institute.
HID--High Intensity Discharge.
hp--Horsepower (force).
HPS--High Pressure Sodium.
HSPF--Heating System Performance Factor.
HVAC--Heating, Ventilating and Air Conditioning.
IEEE--Institute of Electrical and Electronics Engineers, Inc.
IES--Illuminating Engineering Society of North America.

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ILPA--Interior Lighting Power Allowance.
IPLV--Integrated Part Load Value.
ILD--Internal Load Density.
IRF--Internal Reflecting Film.
ISSC--Internal Shading System Coefficient.
Kh--Daylighting Factor.
kVA--Kilo-Volts Amperes.
kW--Kilo-Watts.
LPB--Lighting Power Budget.
LPCC--Lighting Power Control Credits.
LS--Listed Space.
NWMA--National Woodwork Manufacturers Association.
o.c.--On Center.
OLA--Occupant Load Adjustment.
OMB--U.S. Office of Management and Budget.
Pb--Base Unit Lighting Power Allowance.
PAF--Power Adjustment Factor.
PF--Projection Factor.
PTAC--Packaged Terminal Air-Conditioner.
R--Thermal Resistance.
r--Thermal Resistivity.
Sea--Shading Horizontal Adjustment Factor.
SC--Shading Coefficient.
SEER--Seasonal Energy Efficiency Ratio.
Uo--Average Thermal Transmittance.
UL--Underwriter's Laboratories, Inc.
ULPA--Unit Lighting Power Allowance.
UPD--Unit Power Density.
VAV--Variable Air Volume.
VCP--Visual Comfort Probability.
VDT--Visual Display Terminal.
VLT--Visible Light Transmittance.
VSEW--Vertical Surface of the Facade.
W.C.--Water Column.
W--Watts.
W/ft \2\--Watts Per Square Foot.
W/lin. ft--Watts Per Linear Foot.
Wh--Window Height.
WWR--Window Wall Ratio.
WYEC--Weather Year for Energy Conservation Calculations.