Is Your Office Lighting Draining Your Employees’ Energy?

Is Your Office Lighting Draining Your Employees’ Energy?

It wasn’t until the 1940s that artificial lighting became commonplace in work environments. Prior to that time, natural lighting—the lighting we’re just now rediscovering as ideal for employee health—was the primary source of light in offices and factories.1 But to date, not every organization has reintegrated natural lighting into the workplace. In fact, the American Society of Interior Design recently found that 68% of employees were unhappy with their office lighting.

It was nurse Florence Nightingale who first noted how light affected health and recovery: “It is the unqualified result of all my experience with the sick, that second only to their need of fresh air is their need of light; that, after a closed room, what hurts them most is a dark room.”1

Poor lighting and employee health
More recently, Swiss neuroscientist Mirjam Muench discovered that artificial or poor lighting conditions created significant drops in human cortisol levels, which means that we are more stressed, fatigued and less able to stabilize our energy levels when exposed to inadequate lighting.2

Additional employee health issues suspected to be caused or aggravated by poor lighting include:

  1. Migraine headaches
  2. Eye strain
  3. Drowsiness and fatigue
  4. Hormonal imbalance
  5. Disruption of the natural circadian rhythm

How lighting affects employee productivity
Dr. Jacob Israel Liberman, a current oculist and light therapy specialist, noted that under optimal lighting conditions, office workers could concentrate up to eight hours and remain fully focused for two hours under artificial light.3

The National Renewable Energy Laboratory found that workers exposed to natural lighting stayed on task 15% longer than workers who were not exposed to natural lighting. Their study found that natural light increased energy, creativity and productivity.4

A Cornell study5 published in Health Environments Research and Design Journal found that nurses who were exposed to daylight in their places of work reported higher body temperatures and lower blood pressures, and if they worked in stations with windows, they laughed five times more frequently and had eight more episodes of communication versus nurses without outside window exposure.

On the patient side of the coin, the same study found that decreased pain medication, reduced antidepressant effects of some medications, and a reduced hospital stay were the end result of patients who had increased window or daylight exposure.

Even as far back as the 1980s, the U.S. Postal Service recognized lighting as the culprit for productivity. One Reno, Nevada post office renovated their lighting system, resulting in an energy savings of $50,000 per year, but the greatest financial impact they realized was in terms of worker productivity. Their mail sorters soon became the most productive in the western half of the country with the lowest error rates, helping the post office realize a yearly revenue boost of $500,000.6

The heightened employee health benefits and productivity improvements driven by optimized workplace lighting can no longer be ignored—nor should they be—if companies wish to realize peak performance in a challenged economy.

As always, Pacific Gas and Electric Company representatives are readily available to you for additional information on lighting design. Visit the eBook “Lighting Controls and Occupancy Sensors Guide"to learn how advanced lighting controls may benefit your business and its employees.


  1. Nursing Planet
  2. Lighting Research and Technology
  3. Megaman Lighting Design for Quality Living
  4. National Renewable Energy Laboratory
  6. Rocky Mountain Institute and the U.S. Department of Energy