U.S. General Services Administration
6.15 Lighting
Lighting should be designed to enhance both the overall building architecture as well as the effect of individual spaces within the building.
Interior LightingConsideration should be given to the options offered by direct lighting, indirect lighting, down lighting, up lighting and lighting from wall- or floor-mounted fixtures.
Illumination Levels. For lighting levels for interior spaces see the values indicated in Table 6-3. For those areas not listed in the table, the IES Lighting Handbook may be used as a guide.
In office areas with system furniture, assume that under cabinet task lighting is used and provide general illumination of about 300 Lux (30 footcandles) on the work surface. Ceiling lighting branch circuit capacity, however, should be sufficient to provide levels in Table 6-3 for occupancy changes.
Energy Efficient Design. Lighting design must comply with ASHRAE/IES 90.1 as modified by Table 6-4. Power allowances for normal system receptacles include task lighting as shown in Table 6-1. Lighting calculations should show the effect of both general and task lighting assuming that task lighting where it is used has compact fluorescent tubes.
Accessibility for Servicing. Careful consideration must be taken in the design of lighting systems regarding servicing of the fixtures and replacement of tubes or bulbs. This issue needs to be discussed with building operation staff to determine the dimensional limits of servicing equipment.
Light Sources. Generally, interior lighting should be fluorescent. Downlights should be compact fluorescent; high bay lighting should be high intensity discharge (HID) type. HID can also be an appropriate source for indirect lighting of high spaces. However, it should not be used in spaces where instantaneous control is important, such as conference rooms, auditoria or courtrooms.
Dimming can be accomplished with incandescent, fluorescent or HID fixtures, although HID and fluorescent dimmers should not be used where harmonics constitute a problem. Incandescent lighting should be used sparingly. It is appropriate where special architectural effects are desired.
General Lighting Fixture CriteriaLighting Fixture Features. Lighting fixtures and associated fittings should always be of standard commercial design. Custom-designed fixtures should be avoided. They may only be used with express approval from GSA in cases where available standard units cannot fulfill the required function.
Offices and other areas using personal computers or other VDT systems should use indirect or deep-cell parabolic ceiling fixtures. If acrylic lenses or diffusers are used, they should be non-combustible.
Baseline Building Fixture. The fixture to be used for baseline cost comparisons for office space is a 600 mm (2-foot) by 1200 mm (4-foot) 3 lamp fixture utilizing T-8 or CFL lamps and electronic ballasts, deep cell parabolic diffuser, and white enamel reflector.
The number of fixture types and lamp types in the building must be minimized.
Table 6-3 Interior Illumination Levels (Average)
 |
|
| Area | Nominal Illumination Level in Lumens/Square Meter (lux) |
|---|---|
| Office Space | |
Normal work station space, open or closed offices1 |
500 |
ADP Areas |
500 |
Conference Rooms |
300 |
Training Rooms |
500 |
Internal Corridors |
200 |
Auditoria |
150-200 |
Public Areas |
|
Entrance Lobbies, Atria |
200 |
Elevator Lobbies, Public Corridors |
200 |
Ped. Tunnels and Bridges |
200 |
Stairwells |
200 |
| Support Spaces | |
Toilets |
200 |
Staff Locker Rooms |
200 |
Storage Rooms, Janitors’ Closets |
200 |
Electrical Rooms, Generator Rooms |
200 |
Mechanical Rooms |
200 |
Communications Rooms |
200 |
Maintenance Shops |
200 |
Loading Docks |
200 |
Trash Rooms |
200 |
| Specialty Areas | |
Dining Areas |
150-200 |
Kitchens |
500 |
Outleased Space |
500 |
Physical Fitness Space |
500 |
Child Care Centers |
500 |
Structured Parking, General Space |
50 |
Structured Parking, Intersections |
100 |
Structured Parking, Entrances |
500 |
| 1 Level assumes a combination of task and ceiling lighting where systems furniture is used. (This may include a combination of direct/indirect fixtures at the ceiling for ambient lighting.) NOTE: To determine footcandles (fc), divide lux amount by 11. |
|
Table 6-4 System Performance Unit Lighting Power Allowance Common Activity Areas
| UPD Area/Activity |
UPD W/m2 |
Wft2 | Note |
|---|---|---|---|
| Auditoriums | 15.0 | 1.4 | c |
| Corridor | 8.6 | 0.8 | a |
| Classroom/Lecture Hall | 19.4 | 1.8 | |
| Elect/Mech Equipment Room | |||
General |
7.5 16.1 |
0.7 1.5 |
a a |
| Food Service | |||
Fast Food/Cafeteria |
8.6 15.0 14.0 15.0 |
0.8 1.4 1.3 1.4 |
b b |
| Recreation/Lounge | 5.4 | 0.5 | |
| Stairs | |||
Active Traffic |
6.5 4.3 |
0.6 0.4 |
|
| Toilet & Washroom | 5.4 | 0.5 | |
| Garage | |||
Auto & Pedestrian Circulation |
2.7 2.1 |
0.25 0.2 |
|
| Laboratories | 23.7 | 2.2 | |
| Library | |||
Audio Visual |
11.8 16.1 8.6 10.7 |
1.1 1.5 0.8 1.0 |
|
| Lobby (General) | |||
Reception & Waiting |
5.9 4.3 |
0.55 0.4 |
|
| Atrium (Multi-Story) | |||
First 3 Floors |
4.3 1.6 |
0.4 0.15 |
|
| Locker Room & Shower | 6.5 | 0.6 | |
Table 6-4 Continued
| UPD Area/Activity |
UPD W/m2 |
Wft2 | Note |
|---|---|---|---|
| Office | |||
Enclosed offices of less than 900 ft2 and all open plan offices without partitions or with partitions lower than 4.5 ft. below ceiling |
|||
Reading, Typing and Filing |
14.0 23.6 19.4 |
1.3 2.2 1.8 |
d d d |
| Open plan offices, 900ft2 or larger, with medium partitions 3.5 to 4.5 ft. below ceiling | |||
Reading, Typing and Filing |
16.1 28.0 22.6 |
1.5 2.6 2.1 |
a a a |
| Open plan offices, 900ft2 or larger, with large partitions higher than 3.5 ft. below ceiling | |||
Reading, Typing and Filing |
18.3 32.3 25.8 |
1.7 3.0 2.4 |
a a a |
| Common Activity Areas | |||
Conference/Meeting Room |
14.0 22.6 10.7 19.4 |
1.3 2.1 1.0 1.8 |
c |
| Shop (Non-Industrial) | |||
Machinery |
26.9 26.9 17.2 24.7 12.9 |
2.5 2.5 1.6 2.3 1.2 |
|
| Storage and Warehouse | |||
Inactive Storage |
2.1 3.2 9.7 10.7 |
0.2 0.3 0.9 1.0 |
|
| Unlisted Spaces | 2.1 | 0.2 | |
| Notes: | |||
a Area factor of 1.0 shall be used for these spaces. |
|||
Fixture Ballasts. Ballasts should have a sound rating of “A” for 430 MA lamps, “B” for 800 MA lamps and “C” for 1500 MA lamps. Electronic ballasts should be used wherever possible.
Exit Signs. Exit signs shall be of the LED type, have an EnergyStar rating, and meet the requirements of NFPA 101.
Lighting Criteria for Building Spaces
Office Lighting. Office lighting is generally fluorescent lighting. A lighting layout with a fairly even level of general illumination is desirable. Modular (plug-in) wiring for fluorescent lighting fixtures should be used for office areas to facilitate changes. In open office areas with systems furniture partitions, the coefficient of utilization must be reduced to account for the light obstruction and absorption of the partitions.
Design for glare, contrast, visual comfort and color rendering and correction must be in compliance with recommendations contained in the Illuminating Engineering Society of North America (IES) Lighting Handbook.
Task lighting will be used in situations, such as areas of systems furniture, where the general lighting level would be insufficient for the specific functions required.
ADP Areas. Generally, ADP areas should have the same lighting as offices. If the area contains special work stations for computer graphics, dimmable fluorescent lighting may be required. If a large ADP area is segregated into areas of high and low personnel activity, switching design should provide for separate control of lights in high- and low-activity areas of the space.
Conference Rooms and Training Rooms. These spaces should have a combination of fluorescent and dimmable incandescent lighting.
Lobbies, Atria, Tunnels and Public Corridors
Special lighting design concepts are encouraged in these spaces. The lighting design should be an integral part of the architecture.Wall fixtures or combination wall and ceiling fixtures may be considered in corridors and tunnels to help break the monotony of a long, plain space. As stated previously, careful consideration must be taken in the design of lighting systems regarding servicing of fixtures and replacement of lamps.
Mechanical and Electrical Spaces
Lighting in equipment rooms or closets needs to be provided by industrial-type fluorescent fixtures. Care should be taken to locate light fixtures so that lighting is not obstructed by tall or suspended pieces of equipment.
Dining Areas and Serveries
Ample daylight is the illumination of choice in dining areas, assisted by fluorescent fixtures. Limited compact fluorescent lighting for accents is acceptable if comparable architectural effect to incandescent lighting can be achieved.
Character-Defining Spaces in Historic Structures.
Spaces that contribute to the character of a historic structure, as identified the HBPP, should be lighted in a manner that enhances their historic and architectural character. Maintenance and rehabilitation of historic lighting fixtures should be considered, and may be required in the HBPP. Care should be taken to avoid placing fixtures, switches, conduit, or other electrical facilities through character-defining architectural elements.
Structured Parking. Fixtures for parking areas may be fluorescent strip fixtures with wire guards or diffusers. Care must be taken in locating fixtures to maintain the required vehicle clearance. Enclosed fluorescent or HID fixtures should be considered for above-grade parking structures.
High Bay Lighting. Lighting in shop, supply, or warehouse areas with ceilings above 4900 mm (16 feet) should be color-improved high-pressure sodium. In areas where color rendition is known to be of particular importance, metal halide should be used.
Supplemental Emergency Lighting. Partial emergency powered lighting must also be provided in main mechanical, electrical and communications equipment rooms; UPS, battery and ADP rooms; security control centers; fire command centers; the room where the building automation system is located; adjacent to exits; and stairwells. Where CCTV cameras are used for security systems, emergency lighting should be provided at the task area.
Lighting Controls
All lighting must be provided with manual, automatic, or programmable microprocessor lighting controls. The application of these controls and the controlled zones will depend on a number of space factors: frequency of use, available daylighting, normal and extended work hours and the use of open or closed office plans. All of these factors must be considered when establishing zones, zone controls and appropriate lighting control.
Lighting Configuration Benefits. An appropriate lighting configuration can benefit the government; it reduces operating costs by permitting limited operation after working hours, takes advantage of natural light during the daytime working hours and facilitates the subdivision of spaces.
Enclosed Space Lighting Controls. Enclosed space lighting controls may include switches, occupancy sensors, daylight sensors, light level sensors or micro-processors. The lights can be zoned by space or multiple spaces. If microprocessor controls are used to turn off the lights, a local means of override should be provided in every office to continue operations when required.
The following design guidance is provided for enclosed areas:
- Photoelectric sensors that reduce lighting levels in response to daylighting are recommended for small closed spaces with glazing.
- Occupancy sensors should be considered for small closed spaces without glazing.
- Microprocessor control, programmable controller or central computer control are recommended for multiple closed spaces or large zones.
- Touchtone telephone or manual override controls should be provided if microprocessor, programmable controller or central computer control is provided.
Open Space Lighting Controls. Open space lighting controls may include switches, light level sensors for spaces adjacent to glazing and microprocessor controls for zones within the space. If microprocessor controls are used to turn off the lights, a local means of override should be provided to continue operations when required.
Large open space should be subdivided into zones of approximately 100 m2 (1,000 square feet) or one bay. The following guidelines are provided for open plan spaces:
- Controls should be located on core area walls, on permanent corridor walls or on columns
- Remote control schemes and reductions from a programmable controller, microprocessor, and/or central computer should be considered.
Occupancy Sensor Lighting Controls. Infrared, ultrasonic, or passive dual sensors should be considered for small, enclosed office spaces, corridors (if adequate lighting is provided by emergency system) and toilet areas. Each occupancy sensor should control no more than one enclosed space/area. Each occupancy sensor should be marked by a label identifying the panel and circuit number. Occupancy sensors should not be used in open office areas or spaces housing heat producing equipment.
New Orleans, LA
Ambient Light Sensor Controls. Photoelectric sensors should be considered for fixtures adjacent to glazed areas and for parking structures.
Exterior Lighting
Exterior luminaries must comply with local zoning laws. Lighting levels for exterior spaces should be the values indicated by the IES Lighting Handbook. Flood lighting should only be provided if specified in the building program. Exterior lighting of a historic structure should be designed to blend with and support the new architectural characteristics that contribute to the structure’s character.
Parking and Roadway Lighting. Parking and roadway lighting should be an HID source and should not exceed a 10 to 1 maximum to minimum ratio and a 4 to 1 average to minimum ratio.
Parking lots should be designed with high-efficiency, pole mounted luminaries. High- pressure sodium lamps are preferred but consideration should be given to existing site illumination and the local environment. Emergency power is not required for parking lot lighting.
Entrances. Lighting fixtures should be provided at all entrances and exits of major buildings. These exterior lighting fixtures shall be connected to the emergency lighting circuit.
Loading Docks. Exterior door lighting should be provided at loading docks. Fixtures for illumination of the interior of trailers should be provided at each truck position.
Controls. Exterior lighting circuits should be controlled by photocell and a time clock controller to include both all-night and part-night lighting circuits.