Lighting & Productivity

Introduction
In a typical commercial building, the cost of employing people outnumbers the cost of operating a lighting system by some 150 to one.

Therefore, while even as high as a 50 percent reduction in lighting costs using energy-efficient lighting can have a positive impact on the bottom line, just a one percent increase in productivity can dramatically improve profitability. Economists are acknowledging that the economic boom in the 1990s was driven by productivity gains.

Productivity can fluctuate between 50 and 200 percent at any given time for many reasons, including compensation, deadlines, the work environment, outside stresses, work relationships and so on. Lighting also plays an important part, both as an active participant and in a supporting role, and as such has been linked to Indoor Environmental Quality (IEQ) along with thermal comfort and indoor air quality.

The research is difficult to ignore. Here are a few examples of studies that demonstrate a relationship between productivity and lighting:

• An American Society of Interior Designers (ASID) study determined that 68 percent of employees complain about the light in their offices
• The 1989 Steelcase Office Environment index, (Louis Harris), showed that workers consider eye strain as the leading hazard to their health in the office
• A Silicon Valley study found that 79 percent of computer users would like better lighting

By providing the best lighting design to support human interaction with the visual environment, we can support the goals of the space, including worker productivity, retail sales, occupant satisfaction, safety, security, reduced absenteeism, greater competitiveness in leasing--in short, turning good lighting into profit.

Lighting & Human Performance
Between 80 and 85 percent of our impressions of the world are visual. Light makes sight: vision requires a functioning human eye and light. Perception, however, depends on how a space is lighted. And perception, as they say, is reality. With Americans spending an average of 80 percent of their time indoors, most lighting is therefore electric--created, designed and controlled by humans.

The National Lighting Bureau states, "Lighting affects performance in two ways: directly and indirectly. The direct effects occur because lighting alters how well we can see, either by changing the stimuli to the visual system or by changing the operating state of the visual system. The indirect effects occur because lighting can gather attention; alter arousal, mood and behavior; and modify the body's hormone balance."

Therefore, the amount of light available to perform a task is one critical factor, and how the space is lighted is the other.

Introduction

Lighting & Health

Productivity vs. Energy Savings

Sustainable Case Studies

The Importance of Daylighting

Above: PIER stands for Public Interest Energy Research. Their published reports cover integrated energy systems and offer a wealth of information on productivity and building science. If you would like copies of these reports, visit www.newbuildings.org/pier/downloadsFinal.htm