[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: 10CFR435.103]
[Page 410-426]
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. 435.103 Lighting.
3.1 General
3.1.1 This section contains principles of design, a set of minimum
requirements, and two alternative compliance procedures, prescriptive
and systems performance, for the design of building lighting and
lighting control systems, and includes provisions for daylighting
credit. The procedures in this section are solely for use in
establishing lighting design budgets and are not intended for use as
lighting design procedures.
3.1.2 Scope. The following are covered by this section:
3.1.2.1 Interior spaces of buildings;
3.1.2.2 Building exteriors and exterior areas, such as entrances,
exits, and loading docks; and
3.1.2.3 Roads, grounds, parking, and other exterior areas where
lighting is energized through the building electrical service.
3.1.3 Exemptions. The following are exempt from these standards:
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3.1.3.1 Outdoor manufacturing, commercial greenhouses, and
processing facilities;
3.1.3.2 Lighting power for theatrical production studios and
stages, television broadcasting studios, audio-visual presentation, and
entertainment facilities in spaces such as stages, hotel ballrooms,
nightclubs, discos, and casinos, and where lighting is an essential
technical element for the function performed;
3.1.3.3 Specialized luminaires for medical and dental purposes;
3.1.3.4 Outdoor athletic facilities;
3.1.3.5 Lighting power for display lighting required for art
exhibits or displays in galleries, museums and monuments;
3.1.3.6 Exterior lighting for public monuments;
3.1.3.7 Special lighting needs for research;
3.1.3.8 Lighting power for lighting used solely for indoor plant
growth during the hours of 10:00 p.m. to 6:00 a.m.;
3.1.3.9 Emergency lighting that is automatically ``off'' during
normal operation;
3.1.3.10 High risk security areas or any area identified by local
ordinances or regulations or by security or safety personnel as
requiring additional lighting;
3.1.3.11 Lighting power densities for spaces with enhanced lighting
specifically designed for primary use by the visually impaired, hard of
hearing, or for senior citizens;
3.1.3.12 Lighting for signs;
3.1.3.13 Store-front exterior-enclosed display windows in retail
facilities; and
3.1.3.14 Lighting for dwelling units.
3.1.4 Building Lighting Power Allowance. The lighting power
allowance for a building consists of the Exterior Lighting Power
Allowance (ELPA), in accordance with section 3.3, plus the Interior
Lighting Power Allowance (ILPA) in accordance with section 3.4 or 3.5.
This lighting power allowance is the upper limit to which the building
can be designed, based on the criteria of the compliance alternative
chosen.
3.1.4.1 The prescriptive criteria in section 3.4 provides a single
compliance procedure based on calculating a lighting budget by building
type or major area type within which a designer can flexibly design a
lighting solution. To obtain credit for specific lighting energy
conservation measures, use section 3.5, section 11.0, or section 12.0.
3.1.4.2 The systems performance criteria in section 3.5 provides a
more complex compliance procedure based on calculating a lighting budget
by activity or spaces within which the designer can flexibly design a
lighting solution and receive credit for energy conserving controls and
daylighting measures. To receive credit for more complex lighting
conservation measures use section 11.0 or 12.0.
3.1.5 Credit for Daylighting. Daylighting credit, for reduced use
of electric lighting energy resulting from the use of automatic lighting
control devices in conjunction with fenestration (e.g., windows and
skylights), may be taken if the systems performance alternative in
section 3.5 is chosen. However, if such daylighting credit is to be
applied to other building subsystems, such as use of additional
fenestration area, section 11.0 or 12.0 must be used. Thermal credit
provisions for daylighting are found in Section 5.0.
3.1.6 Compliance. A building shall be considered in compliance with
this section if the following conditions are met:
3.1.6.1 The minimum requirements of section 3.3 are met;
3.1.6.2 The exterior lighting power to be installed is not greater
than the Exterior Lighting Power Allowance (ELPA), calculated using
Equation 3.3-1;
3.1.6.3 The interior lighting power to be installed is not greater
than the Interior Lighting Power Allowance (ILPA), based on either the
Prescriptive Criteria in section 3.4 or the Systems Performance Criteria
in section 3.5.
3.1.6.4 Tradeoffs between ILPA and ELPA are not allowed. Tradeoffs
of the interior Lighting Power Budgets (LPB) among interior spaces are
allowed as long as the total Connected Lighting Power (CLP) within the
building does not exceed the Interior Lighting Power Allowance (ILPA)
and Lighting Power Control Credits (LPCC) are used only for connected
lighting power in those spaces for which credit is claimed.
[[Page 412]]
Tradeoffs of exterior lighting power budgets among exterior areas are
allowed as long as the total Connected Lighting Power (CLP) of exterior
lighting does not exceed the Exterior Lighting Power Allowance (ELPA)
and the allowance for the building exterior surfaces is not exceeded.
3.1.7 Multi-Building Facilities. The total lighting power
allowances for each building in a multi-building facility shall be
calculated separately.
3.2 Principles of Design
3.2.1 The lighting system is designed to provide a productive,
safe, and pleasing visual environment for the intended use of the space.
However, lighting is both a major energy end use in commercial buildings
(especially in office buildings) and a major contributor to internal
loads by increasing cooling loads and decreasing heating loads.
Therefore, it is important to produce a design that meets the lighting
functional criteria of the space as well as one that minimizes energy
use. Recommended maintained illuminance levels for visual tasks and
surrounding lighted areas are included in the IES Lighting Handbook,
Applications (1983) or Reference (1985). Principles of energy conserving
design within that context are described below.
3.2.2 The following Design Concepts shall be considered in the
design of lighting that is both energy efficient and visually effective.
3.2.2.1 Energy use is determined by the lighting load (demand
power) and its duration of use (time). Minimize the actual demand load
rather than just the apparent connected load, and control the load
rather than just switching, if switching may adversely affect the
quality of the luminous environment.
3.2.2.2 Consider daylighting along with the proper use of controls
so that the savings from electric lighting can be realized. Design
should be sensitive to window glare, sudden changes in luminances, and
general use acceptance of controls. Window treatment (blinds, drapes and
shades) and glazing should be carefully selected to control direct solar
penetration and luminance extremes while still maintaining view and
daylight penetration.
3.2.2.3 Design lighting systems so that illumination required for
tasks is primarily limited to the location of the task and from a
direction that will minimize direct glare and veiling reflections on the
task. For example, the ideal positioning of work stations is between the
rows of ceiling-mounted luminaires with the direction of view parallel
to the primary task. In densely-occupied work spaces, uniform
distribution of general lighting may be most appropriate. Where
supplementary task illumination is necessary, general or ambient
illumination should not be lower than a third of the luminance required
for the task. This will help maintain luminance rates that are visually
comfortable.
3.2.2.4 Use task lighting, whenever possible, to accommodate the
need for higher lighting levels due to task visual difficulty, glare,
intermittently changing requirements, or individual visual differences
(poor and aging eyesight).
3.2.2.5 Group similar activities so high illuminance or special
lighting for particular tasks are localized in certain rooms or areas,
and so that less efficient fixtures required for critical glare control
do not have to be installed uniformly when they are only required
sparsely.
3.2.2.6 When indirect lighting is appropriate, use schemes that
create reasonably uniform ceiling luminances. If this is achieved, work
spaces may be located anywhere and occupants may face in any direction
without being subject to excessive veiling reflection on the tasks. The
indirect system may allow more effective use of the space than other
types of lighting systems. However, indirect lighting systems generally
have lower utilization factors, and may require increased ceiling height
to provide uniform ceiling luminance.
3.2.2.7 Use lighting controls throughout that maintain proper
lighting levels when and where it is needed but also allow reductions in
lighting when tasks are less critical, or spaces are not fully occupied.
The designer must consider user acceptance of control strategies to
maximize energy efficiency.
[[Page 413]]
3.2.2.8 Use lower levels of ambient lighting in situations such as
merchandising, where the contrast between accent lighting and ambient
lighting is critical. Accent lighting shall not exceed five (5) times
the ambient level. Consider fewer, more effectively-accented displays,
rather than more ineffectively-accented ones.
3.2.3 The following guidelines identify Fixture and Lamp selection
strategies to be considered in the selection of luminaires and lamps for
inclusion in an energy efficient, visually-effective design:
3.2.3.1 Consider the use of more efficient equipment with
appropriate distribution, glare control and visual characteristics.
Utilize fixture designs that will provide high lighting efficiency while
meeting the other lighting objectives of the installation.
3.2.3.2 Review visual comfort probability (VCP) data, available
from manufacturers, for specific luminaires when minimizing discomfort
glare is a criterion.
3.2.3.3 Consider luminaire construction that minimizes light loss
due to dirt collection.
3.2.3.4 Investigate the use of dimmers to reduce energy consumption
when the system is new and capable of providing more light than the
average depreciated design value.
3.2.3.5 Use more efficient lamps with appropriate luminous
efficacy, life expectancy and spectrum distribution and color rendering
characteristics.
3.2.3.6 Use more efficient ballasts for fluorescent and HID lamps
with appropriate ballast factors, power factor, noise rating, starting
and restarting characteristics.
3.2.3.7 Use luminaires with heat removal and heat recovery
capabilities, thereby allowing the lighting equipment to operate more
efficiently at a lower ambient temperature.
3.2.3.8 Limit the use of lower efficiency lamps, such as
incandescent, to only those applications where their color, lumens or
distribution characteristics cannot be duplicated by other sources. Due
to their lower efficiency, the use of ``extended service'' incandescent
lamps should be limited to those applications where fixtures are
difficult to reach and/or maintenance costs for revamping will be
excessive.
3.2.4 Space Design
3.2.4.1 It is important to carry through on the lighting design
when completing the interior design. Reduce light absorption by
encouraging the use of lighter finishes, particularly on ceilings, walls
and partitions. Select colors and surface materials so that their
reflectance values are within the ranges recommended by the IES. This
will aid the efficient use of light and help to provide comfortable
luminance ratios.
3.2.4.2 In offices with visual display terminals (VDT) that are
susceptible to reflections, it may be necessary to use reflectances for
some room surfaces at the low end of the recommended ranges to reduce
unwanted reflections on the screens. Where practical, treat the screens
of VDTs with anti-glare materials to avoid veiling reflection.
3.3 Minimum Requirements
3.3.1 Lighting Controls.
3.3.1.1 All lighting shall be provided with manual, automatic, or
programmable controls.
3.3.1.1.1 Exception to Section 3.3.1.1:
(a) controls for emergency or exit lighting.
3.3.1.2 Minimum Number of Lighting Controls. Each space enclosed by
walls or ceiling-height partitions shall be provided with control(s)
that, together or alone are capable of controlling all lights within
that space, excluding those requiring continuous operation for security
purposes.
3.3.1.2.1 The minimum number of controls shall not be less than:
(a) One lighting control for each space; and
(b) One lighting control for each task or group of task locations
within an area of 450 ft\2\ or less.
3.3.1.2.2 Equivalent Number of Controls. The minimum number of
controls may be reduced, by using an equivalent number of controls from
Table 3.3-1, where control types listed in Table 3.3-1 are used.
However, the minimum number of controls may not be reduced to less than
one control for each 1500 W of connected lighting power.
[[Page 414]]
[GRAPHIC] [TIFF OMITTED] TC04OC91.082
3.3.1.2.3 Exceptions to Section 3.3.1.2:
(a) Lighting control requirements for spaces that must be used as a
whole, such as public lobbies of office buildings, hotels, and
hospitals; retail and department stores and warehouses, storerooms, and
service corridors under centralized supervision, shall be controlled by
a lesser number of controls, but not less than one control for each 1500
W of connected lighting power, or a total of three (3) controls,
whichever is greater. Lighting in such spaces shall be controlled in
accordance with the work activities.
(b) Hotel and motel guest rooms shall have one or more master
controls at the main entry door that turn off all permanently wired
lighting fixtures and lighting and television receptacles. For multiple
room suites, controls at the entry of each room, in lieu of a master
switch, will meet these requirements.
3.3.1.3 Controls provided for task areas, if readily accessible,
may be mounted as part of the task lighting luminaire.
3.3.1.4 Control of the same load from more than one location shall
not be credited as additional control points.
3.3.1.5 All lighting controls shall be readily accessible to
personnel occupying or using the space. Exceptions are automatic
controls, programmable controls, lighting for safety hazards and
security, controls requiring trained operators, and those controls for
spaces that must be used as a whole.
3.3.1.6 Exterior lighting shall be automatically controlled by
timer, photocell, or combination of timer and photocell. Timers shall be
of the automatic type or otherwise capable of adjustment for seven days
and for seasonal daylight schedule variations. All time-controllers
shall be equipped with back-up mechanisms to keep time during a four
hour power outage.
3.3.1.7 When the building is served by an energy management system,
programmable controls, shared tenant services that affect interior
environments, or ``intelligent building'' systems, provisions shall be
made to incorporate lighting controls into the system if a separate
automatically-controlled lighting system is not provided.
3.3.2 Fluorescent Lamp Ballasts.
3.3.2.1 Fluorescent lamp ballasts shall have a ballast efficacy
factor not less than that shown in Table 3.3-2.
3.3.2.1.1 Exception to 3.3.2.1: Ballasts not included in Table 3.3-
2 and ballasts designed for use with dimming controls are excluded from
these criteria.
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[GRAPHIC] [TIFF OMITTED] TC04OC91.083
3.3.2.2 The Ballast Efficacy Factor shall be calculated in
accordance with Equation 3.3-1:
[GRAPHIC] [TIFF OMITTED] TC14NO91.059
Equation 3.3-1
Where:
BEF=Ballast Efficacy Factor.
BF=Ballast Factor, expressed as a percent.
Power Input=Total Wattage of combined lamps and ballasts
3.3.2.2.1 Tests for ballast factor and power input shall be in
accordance with ANSI Standard C-82.2-1984 ``Method of Measurement for
Fluorescent Lamp Ballasts'', using ``Standard'' F40T1240A, F96T12 75
watt, or F96T12H0 110 watt lamps.
3.3.2.3 One-lamp or three-lamp fluorescent luminaires shall be
tandem-wired to eliminate unnecessary use of single lamp ballasts if
they are: used for general lighting; recess mounted within ten feet
center-to-center of each other; or pendant or surface mounted within 1
ft of each other, and within the same room. Tandem wiring consists of
pairs of luminaires operating with one lamp in a luminaire powered from
a single two-lamp ballast contained in a second luminaire.
3.3.2.3.1 Exception to Section 3.3.2.3:
(a) Three-lamp ballasts may be used.
3.3.2.4 Fluorescent lamp ballasts shall have a power factor equal
to or greater than 80%.
3.3.2.4.1 Exception to 3.3.2.4: Ballasts for circline and compact
fluorescent lamps and low wattage, high intensity discharge lamps of
less than 100 watts.
3.4 Lighting--Prescriptive Compliance Alternative
3.4.1 Purpose
3.4.1.1 This subsection provides a prescriptive procedure for
determining an exterior lighting power allowance and the Interior
Lighting Power Allowances for illumination systems installed in six
types of new buildings. It is intended for use with buildings having
simple lighting requirements and where the minimum amount of calculation
and effort to achieve compliance is of primary concern. For other
building types, to receive credit for switching, daylighting, or other
trade-offs, or to receive credit for lighting optimization, use section
3.5, section 11.0, or section 12.0.
[[Page 416]]
3.4.1.2 This section also serves as the basis for calculating the
skylight area in section 5.3.9.6, and may be used for estimating the
lighting heat gain for calculating the internal load density in Equation
5.4-1 and section 5.5.6.2.
3.4.2 General
3.4.2.1 This method for compliance prescribes a total allowable
Unit Lighting Power Allowance (ULPA) for interior lighting for the
building type/area as listed in Table 3.4-1. There is no recognition of
specific makeup of spaces and activities within the building.
[GRAPHIC] [TIFF OMITTED] TC04OC91.084
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3.4.3 Exterior Lighting Power Allowance
3.4.3.1 Building exteriors and exterior areas, as defined in
section 3.1.2.2, and roads, grounds, parking, and other exterior areas,
defined in section 3.1.2.3, shall have a lighting power density not to
exceed the Exterior Lighting Power Allowance (ELPA), which is the sum of
the allowances for each of the areas listed above, as calculated by
Equation 3.4-1 using unit power densities from Table 3.4-2.
[GRAPHIC] [TIFF OMITTED] TC04OC91.085
ELPA= DOi UPDDi+ Ai
UPDAi= [(DO1 x UPDD1
. . .+DOn x UPDDn)+
(A x UPDA1 . . .
An x UPDAn)]
Equation 3.4-1
Where:
ELPA=Exterior lighting power allowance, in Watts.
[[Page 418]]
i=numerical subscript (1,2, . . . . n) for each occurrence of exterior
openings or exterior areas of the building.
n=total number of occurrences of exterior openings or areas of the
building.
DO=Door opening, linear feet.
UPDD=Unit power density for the door, W/lin. ft, from Table
3.4-2.
UPDA=Unit power density for the area in W/ft \2\, from Table
3.4-2.
A=Exterior area in ft2.
3.4.4 Interior Lighting Power Allowance
3.4.4.1 The Interior Lighting Power Allowance (ILPA) shall be
calculated using the prescriptive Unit Lighting Power Allowances (ULPA)
in Table 3.4-1. First, determine if the predominant function of the
proposed building is one of the six building types listed in Table 3.4-
1. If not, section 3.5, 11.0, or 12.0 must be used. Next, determine
whether the proposed design has secondary functions that are 10% or more
of the gross lighted area of the building and are listed in Table 3.4-1.
If so, the designer has the option of using the predominant building
function to calculate the ILPA or using the calculation method for
multiple-use buildings in section 3.4.4.1.2 below.
3.4.4.1.1 If the proposed building has only one function, has no
secondary functions with 10% or more of the gross lighted area, or the
designer chooses to determine the ILPA based on only one function,
Equation 3.4-2 shall be used to determine the building ILPA. First,
select the appropriate building type in Table 3.4-1, and the appropriate
column for the Gross Lighted Area (GLA) of the proposed building. This
value is the Unit Lighting Power Allowance (ULPA). Determine the ILPA by
multiplying the ULPA by the GLA as shown in Equation 3.4-2.
ILPA=ULPA x GLA
Equation 3.4-2
Where:
ILPA=Interior Lighting Power Allowance, in Watts.
ULPA=Unit Lighting Power Allowance, in W/ft\2\,from Table 3.4-1.
GLA=Gross Lighted Area of the Proposed Building, in ft\2\.
3.4.4.1.2 If a building design has more than one function listed in
Table 3.4-1, such as an office building with parking and retail stores,
with more than 10% of the gross lighted area, Equation 3.4-3 may be used
to calculate the building Interior Lighting Power Allowance (ILPA).
First, determine the gross lighted area of the building (GLA) and the
gross lighted area for each qualifying secondary function
(GLAf) in the building. Select the ULPA from Table 3.4-1
under the column corresponding to the gross lighted area of the entire
proposed building and multiply it by the gross lighted area of that
function. Sum the products to determine the building ILPA, as shown in
Equation 3.4-3 below.
ILPA=ULPAp GLAp+(ULPAi
GLAi)= [ULPAp
GLAp+(ULPAf1 GLAf1+
ULPAf2 GLAf2 . . . ULPAfn
GLAf)]
Equation 3.4-3
Where:
i=numerical subscript (1,2, . . . n) for each secondary function with
10% or more of the gross lighted area of the building.
n=number of secondary functions.
ILPA=Interior Lighting Power Allowance, in Watts.
ULPAp=Unit Lighting Power Allowance of the predominant
function based on the gross lighted area of the entire
building, from Table 3.4-1, in W/ft2.
ULPAf=Unit Lighting Power Allowance of qualifying secondary
functions based on the gross lighted area of the entire
building, from Table 3.4-1, in W/ft2.
GLAp=Gross lighted area of the predominant function of the
proposed building.
GLAf=Gross lighted area of each qualifying secondary
function.
3.4.4.3 Lighting compliance in partially defined speculative
buildings. For defined functions in partially defined speculative
buildings, the total connected lighting power shall not exceed the
interior lighting power allowance for that portion of the building. When
determining the ILPA for those cases, the gross lighted area of the
entire building must be used.
3.5 Lighting--System Performance Compliance Alternative
3.5.1 Purpose
3.5.1.1 This subsection provides a procedure for determining the
maximum lighting power allowance for buildings, roads and grounds. It
allows the designer to take credit for the use
[[Page 419]]
of daylighting and other lighting controls. It also serves as a basis
for estimating the lighting heat gain and lighting energy use for
Section 5.0.
3.5.2 General
3.5.2.1 The total Connected Lighting Power (CLP) in a building,
including permanently installed lighting plus supplemental or task
related lighting provided by movable fixtures or plug-in luminaires,
shall not exceed the Interior Lighting Power Allowance (ILPA). A
Lighting Power Control Credit (LPCC), taken for individual spaces, may
only be utilized for credit to connected lighting power in those spaces
for which credit is claimed.
3.5.2.2 Compliance for lighting in partially defined speculative
buildings. The total connected lighting power of lighting designs of
defined areas of partially defined speculative buildings shall not
exceed the interior lighting power allowance for those areas of the
building for which lighting has been designed.
3.5.3 The Lighting Power Budget (LPB) of each interior space shall
be determined in accordance with Equation 3.5-1.
LPB=(A x UPDb x AF)+LPCC
Equation 3.5-1
Where:
LPB=Lighting power budget of the space, in watts
Ar=Area of the room at the horizontal lighted working place,
ft2
UPDb=Base Unit Power Density, W/ft2, (Table 3.5-1)
AF=Area factor of the room, (Figure 3.5-1)
LPCC=Lighting Power Control Credit, as determined by Sec. 3.5.6
3.5.3.1 The room area (A) shall be calculated from the inside
dimensions of the room.
3.5.3.2 The Base Unit Power Density (UPD) shall be selected from
Table 3.5-1. For applications to areas or activities other than those
given, select values for similar areas or activities.
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[GRAPHIC] [TIFF OMITTED] TC04OC91.087
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[GRAPHIC] [TIFF OMITTED] TC04OC91.088
3.5.3.3 The Area Factor (AF) shall be determined from Figure 3.5-1
based on the floor area and ceiling height of the room. Rooms with
identical ceiling height and activities, and with similar size may be
treated as a group. The AF
[[Page 423]]
of such a group of rooms shall be determined from the average area of
the rooms.
Equation 3.5-2 gives the formula used in developing Figure 3.5-1.
[GRAPHIC] [TIFF OMITTED] TC04OC91.089
Equation 3.5-2
Where:
AF=Area Factor
CH=Ceiling Height
Ar=Floor Area of Room, ft2
If AF<1.0 then AF=1.0
If AF>1.8 then AF=1.8
[[Page 424]]
[GRAPHIC] [TIFF OMITTED] TC04OC91.090
3.5.4 Special Spaces and Activities.
3.5.4.1 Multi-Function Rooms.
3.5.4.1.1 For rooms serving multi-functions, such as hotel banquet/
meeting rooms and office conference/presentation rooms, an adjustment
factor of 1.5 times the base UPD may be used if
[[Page 425]]
a supplementary lighting system is actually installed to serve the
secondary function of the room and the design meets the following
conditions:
(a) The installed power for the supplementary system shall not be
greater than 33% of the adjusted LPB calculated for that room; and
(b) Independent controls shall be installed for the supplementary
lighting system.
3.5.4.2 Simultaneous Activities.
3.5.4.2.1 In rooms containing multiple simultaneous activities,
such as a large general office having separate accounting and drafting
areas within the same room, the LPB for the rooms shall be the weighted
average of the activities in proportion to the areas being served.
3.5.4.3 Indoor Sports.
3.5.4.3.1 The floor area of indoor sports activities areas shall be
considered as the area within the playing boundaries of the sport, plus
the floor area 10 ft beyond the playing boundaries, not to exceed the
total floor area of the indoor room less the spectator seating area.
3.5.5 Calculation of Interior Lighting Power Allowance. The system
performance Interior Lighting Power Allowance (ILPA) shall be calculated
in accordance with Equation 3.5-3. The ILPA shall include a 0.20 W/
ft2 allowance for unlisted spaces.
ILPA=(LPB1 x LS1+LPB2 x LS2--
--LPBn x LSn)+0.2 W/
ft2 x (Unlisted Space)
Equation 3.5-3
Where:
ILPA=Interior Lighting Power Allowance, W/ft2
[GRAPHIC] [TIFF OMITTED] TC14NO91.060
GLA=Gross Lighted Area, ft2
LPB=Lighting Power Budget, Watts
LS=Listed Space Area, ft2
3.5.6 Lighting Power Controls Credit and Power Adjustment Factor
3.5.6.1 When calculating the ULPA in this section, the connected
power for lights automatically controlled by daylighting sensors,
occupancy sensor, programmable timing controls, or lumen maintenance
controls may be reduced by factoring control credits on a specific area
by area basis. This credit is termed the Lighting Power Controls Credit
(LPCC) and shall be determined in accordance with Equation 3.5-4:
LPCC=CLP x PAF
Equation 3.5-4
Where:
LPCC=Lighting Power Controls Credit, Watts
CLP=Connected Lighting Power for the luminaires controlled by the
automatic control device, Watts
PAF=Power Adjustment Factor, from Table 3.5-2
The adjusted lighting power (ALP) is then equal to CLP minus the LPCC.
3.5.6.2 The Lighting Power Controls Credit is limited to the
specific luminaires controlled by the automatic control device.
3.5.6.2.1 Only one adjustment factor may be used for each building
space or luminaire, and 50% or more of the controlled luminaire shall be
within the applicable space to qualify for the power adjustment factor.
3.5.6.2.2 Controls shall be installed in series with the lights and
in series with all manual switching devices in order to qualify for an
adjustment factor.
3.5.6.2.3 When sufficient daylight is available, daylight sensing
controls shall be capable of reducing electrical power consumption for
lighting, continuously or in steps, to 50% or less of maximum power
consumption.
3.5.6.2.4 Daylight sensing controls shall control all luminaires to
which the power adjustment factor is applied and that direct a minimum
of 50% of their light output into the daylight zone.
3.5.6.2.5 Occupancy sensors located in daylighted spaces should be
installed in conjunction with a manual ON switch, or photocell override
for ON.
3.5.6.2.6 Programmable timing controls used for credit in
conjunction with Table 3.5-2 shall be:
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[GRAPHIC] [TIFF OMITTED] TC04OC91.091
(a) Programmable for different schedules for occupied and unoccupied
days;
(b) Accessible for temporary override by occupants of individual
zones, spaces or tasks, with automatic return to the original schedules;
and
(c) Capable of keeping time during power outages for a minimum of
four hours.