General Lighting
The lighting system plays a significant role in the overall indoor environmental quality of the office space.1,2 General lighting is designed to provide a substantially uniform level of illuminance throughout an area, exclusive of any provision for special local requirements.3 General lighting selection should be driven by efficiency, lamp life, color quality of the light, and its intended use with a combination of direct (downward) and indirect (upward) light sources. The ceiling layout impacts the effectiveness of a general lighting scheme. Use a non-uniform lighting layout to give more visual stimulation and appeal, supplemented as appropriate with daylighting, task lighting and accent lighting.
- Optimizing daylighting and providing views to the outdoors has been demonstrated to increase occupant performance and reduce absenteeism.4 Integration of shading and glare control strategies avoids eye strain while individual lighting controls and task lighting gives occupants the ability to control their lighting conditions.
- Task lighting is directed to a specific surface or area, providing illumination for visual tasks.3 In the office environment, providing task lighting at individual workstations and desks allows occupants control of their visual space and could reduce the need for general lighting.
- Accent lighting is directional lighting to emphasize a particular object or surface feature, or to draw attention to a part of the field of view.3 Selective illumination, often located in entrance and lobby areas, can improve wayfinding, add brightness, create dramatic effects, and highlight points of visual interest.
Lighting system components are lamps, fixtures (reflectors, diffusers, and lens), ballasts (for some types of lamps), and controls. Light Emitting Diode (LED) lamps have become common in most workplace environments, but fluorescent and High-Intensity Discharge (HID) lamps may be preferred for certain applications. Consider the lamp, fixture, and appropriate controls, as well as ceiling, floor, and wall surface reflectance values, to maximize light levels while minimizing energy consumption.
Use the Green Procurement Compilation (GPC) for guidance on procuring Lighting and SFTool Product Search to find compliant products.
For guidance on selecting the most cost-effective and energy-efficient lighting systems available, see GSA's LED Lighting and Controls Guidance.
1. Committee to Review and Assess the Health and Productivity Benefits of Green Schools (2006). Review and Assessment of the Health and Productivity Benefits of Green Schools: An Interim Report. National Research Council, National Academy of Sciences.
2. Heschong-Mahone Group (2003). Windows and classrooms: A Study of Student Performance and the Indoor Environment. Sacramento, CA: California Energy Commission.
3. Illuminating Engineering Society | General Lighting
4. Milton, D.K., P.M. Glencross, and M.D. Walters (2000). Risk of Sick Leave Associated with Outdoor Air Supply Rate, Humidification, and Occupant Complaints. Indoor Air, 2000. 10(4): p. 212-21.
Bundles:
Building Automation
Cost-Effective IEQ Upgrade
System Relationships
HVAC
<p>Minimizing waste heat from lighting fixtures allows the cooling system to run more efficiently.</p>