5.6 Prescriptive Compliance Approach for Indoor Lighting

1. The adjusted indoor lighting power of all proposed building areas combined, when calculated in accordance with §140.6(a), is no greater than the allowed indoor lighting power, calculated in accordance with §140.6(c).

2. The calculation of allowed indoor lighting power meets the requirements in §140.6(b).

5.6.2 Calculation of Adjusted Indoor Lighting Power

The adjusted indoor lighting power of all building areas is the total watts of all planned permanent and portable lighting systems in the proposed building.

Some adjustments are available to reduce the reported indoor lighting power. These adjustments are discussed below.

A. Power Adjustment Factors or Reduction of Wattage Through Controls

The Energy Code provides an option for a lighting power reduction credit when specific lighting controls are installed, provided those lighting controls are not required.

A power adjustment factor (PAF) is an adjustment to the installed lighting power in an area that allows some of the installed lighting power to not be counted toward the building’s total installed lighting load.

In calculating adjusted indoor lighting power, the installed watts of a luminaire providing general lighting in a functional area listed in Table 140.6-C|tag=TABLE_140_6_C may be reduced by multiplying the watts controlled by the applicable power adjustment PAF, per Table 140.6-A.

1. The person who is eligible under Division 3 of the Business and Professions Code to accept responsibility for the construction or installation of features, materials, components, or manufactured devices must sign and submit the certificate of installation before a PAF will be allowed for compliance with §140.6. If any of the requirements in this Certificate of Installation are not met, the installation shall not be eligible to use the PAF.

3. The controlled lighting is permanently installed general lighting systems and the controls are permanently installed nonresidential-rated lighting controls (portable lighting, portable lighting controls, and residential rated lighting controls do not qualify for PAFs).

When used for determining PAFs for general lighting in offices, furniture-mounted luminaires shall qualify as permanently installed general lighting systems if:

c. They are designed to provide indirect general lighting. (They may also have elements that provide direct task lighting.)

d. The lighting control for the furniture mounted luminaire complies with all other applicable requirements in §140.6(a)2.

Before multiplying the installed watts of the furniture-mounted luminaire by the applicable PAF, 2 watts per square foot of the area illuminated by the furniture mounted luminaires shall be subtracted from installed watts of the furniture mounted luminaires to account for portable lighting.

4. At least 50 percent of the light output of the controlled luminaire is within the applicable area listed in Table 140.6-A. Luminaires on lighting tracks must be within the applicable area to qualify for a PAF.

5. Only one PAF from Table 140.6-A may be used for each qualifying luminaire. PAFs shall not be added together unless specifically allowed in Table 140.6-A.

6. Only lighting wattage directly controlled in accordance with §140.6(a)2 shall be used to reduce the calculated adjusted indoor lighting power as allowed by §140.6(a)2. If only a portion of the wattage in a luminaire is controlled in accordance with §140.6(a)2, then only that portion of controlled wattage may be reduced in calculating adjusted indoor lighting power.

7. Lighting controls used to qualify for a PAF shall be designed and installed in addition to manual, multilevel, and automatic lighting controls required in §130.1, and in addition to any other lighting controls required by the Energy Code.

8. To qualify for the PAF for daylight continuous dimming plus off control, the following requirements must be met:

a. The daylight control and controlled luminaires must meet the requirements of §130.1(d), 130.4(a)3, and 130.4(a)7.

b. The daylight control shall be continuous dimming and shall additionally turn lights completely off when the daylight available in the daylit zone is greater than 150 percent of the illuminance received from the general lighting system at full power.

9. To qualify for the PAF for an occupant sensing control controlling the general lighting in large office areas above workstations, in accordance with Table 140.6-A, each occupant sensing control zone must be 250 square feet or smaller and the following requirements must be met (note that occupant sensing controls are already required in offices greater than 250 square feet per §130.1(c)6D, and each occupant sensing control zone may not be greater than 600 square feet (refer to Section 5.4.3 for more information); This PAF is provided when the occupant sensing control zones are 250 square feet or smaller):

c. Controlled luminaires may only be those that provide general lighting directly above the controlled area or furniture-mounted luminaires that comply with §140.6(a)2 and provide general lighting directly above the controlled area.

d. Qualifying luminaires must be controlled by occupant sensing controls that meet the following requirements, as applicable:

i. Infrared sensors shall be equipped (either by the manufacturer or in the field by the installer) with lenses or shrouds to prevent them from being triggered by movement outside the controlled area.

ii. Ultrasonic sensors shall be tuned to reduce their sensitivity, to prevent them from being triggered by movements outside the controlled area.

iii. All other sensors shall be installed and adjusted as necessary to prevent them from being triggered by movements outside the controlled area.

e. The PAF shall be applied only to the portion of the installed lighting power that is controlled by the occupant sensors, not to the total installed lighting power.

f. The value of the PAF (0.2 or 0.3) depends on the square footage controlled by each occupant sensor.

10. The following requirements must be met to qualify for the institutional tuning PAF:

a. The lighting controls must limit the maximum output or maximum power draw of the controlled lighting to 85 percent or less of full light output or full power draw.

b. The means of setting the limit must be accessible only to authorized personnel.

c. The setting of the limit must be verified by the acceptance test required by §130.4(a)7.

d. The construction documents must specify which lighting systems will have their maximum light output or maximum power draw set to no greater than 85 percent of full light output or full power draw.

11. To qualify for the Demand Responsive Control PAF, the general lighting wattage receiving the PAF must not be within the scope of §110.12(c) and the following requirements must be met:

a. The controlled lighting must be capable of being automatically reduced in response to a demand response signal.

b. General lighting must be reduced in a manner consistent with the uniform level of illumination requirements in Table 130.1-A.

Requirements of §110.12(c): Buildings with nonresidential lighting systems having a total installed lighting power of 4,000 watts or greater that is subject to the requirements of §130.1(b) shall install controls capable of automatically reducing lighting power in response to a Demand Response Signal. See Section 5.4.5 of this manual for more information.

12. To qualify for the PAF for daylighting devices (including clerestories, light shelves, and horizontal slats) in Table 140.6-A, the daylighting devices must meet the requirements in §140.3(d). The PAFs shall only apply to lighting in a primary or secondary sidelit daylit zone where continuous dimming daylighting controls meeting the requirements of §130.1(d) are installed.

Refer to Chapter 3 for more information on the requirements for daylighting devices that qualify for a PAF.

B. Luminaire Power Adjustment

Color-tunable LED lighting technologies are available for lighting applications including hospitality, healthcare, and other uses. This technology produces correlated color temperatures (CCT) that match the current use of a space.

Two categories of color tunable luminaires – tunable-white LED and dim-to-warm LED luminaires – can qualify for a luminaire lighting power adjustment multiplier of 0.80 if the luminaire meet all of the requirements of §140.6(a)4B, paragraphed below:

• Small Aperture: Luminaire aperture width no wider than 4 inches for an aperture length longer than 18 inches; aperture width no wider than 8 inches otherwise.

• Color Changing Capability: Capable of color change greater than or equal to 2000K CCT for tunable-white LED luminaires; capable of color change greater than or equal to 500K CCT for dim-to-warm LED luminaires.

• Controls: Connected to controls that allow color changing of the illumination.

Figure 5-21: Example of Dim-to-Warm Lighting: An Indoor Space With Dim-to-Warm Luminaires (top); Relationship of Dimming to Change in Correlated Color Temperature of Dim-to-Warm (aka “WarmDim”) Lighting Technology (bottom image)

Image Source: Juno WarmDimming® Dimming courtesy of Acuity Brands Lighting, Inc.

C. Portable Lighting in Office Areas

Section 140.6(a) of the Energy Code requires that all planned lighting, including portable and permanent lighting systems, be counted toward the lighting energy use of the building, regardless of when it is planned to be installed.

Because office cubicles (including their portable lighting) are typically not installed until after the building inspection is complete, the portable lighting power is counted together with the permanent lighting as the adjusted lighting power for compliance. When using the area category method for offices with portable lighting, the additional lighting power provision is available for portable lighting and decorative/display lighting. Refer to Section 5.7.3 for more information about the area category method.

The Energy Code defines portable lighting as lighting with plug-in connections for electric power. That includes table and floor lamps, those attached to modular furniture, workstation task luminaires, luminaires attached to workstation panels, those attached to movable displays, or those attached to personal property.

D. Two Interlocked Lighting Systems

Within the following five functional areas, as defined in §100.1, two lighting systems may be installed provided they are interlocked so that both lighting systems cannot operate simultaneously. All other functional areas are permitted to install only one lighting system.

No more than two lighting systems may be used for these five specifically defined functional areas, and if there are two lighting systems, they must be interlocked.

Where there are two interlocked lighting systems, the lower-wattage system may be excluded from determining the adjusted indoor lighting power if:

1. The person who is eligible under Division 3 of the Business and Professions Code to accept responsibility for the construction or installation of features, materials, components, or manufactured devices must sign and submit the certificate of installation before two interlocked lighting systems will be recognized for compliance.

2. If any of the requirements in the certificate of installation are not met, the two interlocked lighting systems will not be recognized for compliance.

3. The two lighting systems shall be interlocked with a nonprogrammable double-throw switch to prevent simultaneous operation of both systems.

For compliance with the Energy Code, a nonprogrammable double-throw switch is an electrical switch commonly called a "single pole double throw" or "three-way" switch that is wired as a selector switch allowing one of two loads to be enabled. It can be a line voltage switch or a low-voltage switch selecting between two relays. It cannot be overridden or changed in any manner that would permit both loads to operate simultaneously.

E. Lighting Wattage Not Counted Toward Building Load

The Energy Code does not require the lighting power of certain types of luminaires in specific functional areas, or for specific purposes, to be counted toward the installed lighting power of a building. For example, lighting in the guest rooms of hotels is not required to be counted for compliance with §140.6. However, lighting in all other function areas within a hotel are required to comply with all applicable requirements in §140.6. Lighting in guest rooms is, however, regulated by the low-rise residential lighting standards.

The wattage of the following indoor lighting applications may be excluded from the adjusted (installed) indoor lighting power:

• Studio lighting for film or photography provided that these lighting systems are in addition to and separately switched from a general lighting system.

• Lighting for dance floors, theatrical and other live performances, and religious worship provided that these lighting systems are in addition to a general lighting system and are separately controlled by a multiscene or theatrical cross-fade control station accessible only to authorized operators.

• Lighting intended for makeup, hair, and costume preparation in performance arts facility dressing rooms if the lighting is switched separately from the general lighting system, switched independently at each dressing station, and controlled with a vacancy sensor.

• Lighting for temporary exhibits in civic facilities, transportation facilities, convention centers, and hotel function areas if the lighting is an addition to a general lighting system and is separately controlled from a panel accessible only to authorized operators.

• Lighting installed by the manufacturer in walk-in freezers, vending machines, food preparation equipment, and scientific and industrial equipment.

• Examination and surgical lights, low-ambient night-lights, and lighting integral to medical equipment, if this lighting is in addition to and switched separately from a general lighting system.

• Lighting for plant growth or maintenance in non-controlled environment horticulture spaces, if it is controlled by a multilevel astronomical time-switch control that complies with the applicable provisions of §110.9.

• Lighting that is required for exit signs subject to the CBC. Exit signs shall meet the requirements of the Appliance Efficiency Regulations.

• Exit way or egress illumination that is normally off and that is subject to the CBC.

• In hotel/motel buildings: Lighting in guest rooms (lighting in hotel/motel guest rooms must comply with §130.0(b). (Indoor lighting not in guest rooms must be in compliance with all applicable nonresidential lighting requirements in the Energy Code.)

• Temporary lighting systems. Temporary lighting is defined as a lighting installation with plug-in connections that does not persist beyond 60 consecutive days or more than 120 days per year.

• Lighting systems in qualified historic buildings, as defined in the State Historic Building Code (Title 24, Part 8), are exempt from the lighting power allowances if they consist solely of historic lighting components or replicas of historic lighting components. If lighting systems in qualified buildings contain some historic lighting components or replicas of historic components, combined with other lighting components, only those historic or replica components are exempt. All other lighting systems in qualified historic buildings shall comply with the lighting power allowances.

• Lighting in nonresidential parking garages for seven or fewer vehicles must comply with the applicable residential parking garage provisions of §150.0(k).

• Lighting in refrigerated cases smaller than 3,000 sq ft. must comply with the Appliance Efficiency Regulations.

• Lighting connected to a life safety branch or critical branch, as specified in Section 517 of the California Electrical Code.

Nonresidential indoor lighting applications not listed above must comply with all applicable nonresidential indoor lighting requirements.

Example 5-17: Lighting Power Exceptions and Control Requirements

Question

For indoor lighting, if lighting is excluded from the indoor power limitations per §140.6(a)3, is that lighting also excluded from the indoor lighting control requirements of §130.1?

Answer

No. Indoor lighting excluded from the power limitations of §140.6 is not necessarily exempt from the mandatory control requirements of §130.1. These sections are independent of each other.