Letter to the Editors: Lighting for Different Healthcare Settings

Abstract

According to Michael White, Light should be interpreted as an architectural material. Mr. White made his pronouncement at the Annual Conference of the Academy of Neurosci- ence for Architecture in September 2012, and went on to say that in addition to being economically sound and aesthetically pleasing, the specification of light should address the biology of human health and well being.Mr. White, an EDAC-certified senior lighting design consultant for the firm Shuler Shook in Minneapolis, Minnesota, was a guest speaker in a panel session titled That Informs Light- ing Design in Healthcare Settings. The other pan- elists were Sanchin Panda, PhD, a neuroscientist at the Salk Institute for Biological Studies in La Jolla, California, where the conference was being held; Eve Edelstein, PhD, a neuroscientist and associate professor at the University of Arizona College of Architecture, Planning, and Landscape Architec- ture; and Mark Rea, PhD, a biophysicist and direc- tor of the Lighting Research Center at Rensselaer Polytechnic Institute. Like his colleagues, White was concerned with the use of indoor electrical lighting.People living and working today in the most advanced industrial countries spend the majority of their daylight hours and an average of six hours after nightfall under artificial light. Research has shown that in the absence of full-spectrum sun- light, individuals are susceptible to detrimental effects (Veitch et al., 2008). Conventional candes- cent and/or fluorescent lamps have been implicated in aggravating fatigue, depression, aggression, eye strain, dyslexia, tooth decay, reduced muscle strength, obesity, and diabetes. The lack of exposure to ultraviolet radiation impairs the body's ability to absorb calcium, produce vitamin D3, and stimulate the neuroendocrine system to destroy a wide range of microorganisms that might otherwise lead to hospital-acquired infections (Braun, 2008). In the 1960s, fluorescent lamps were engineered to simulate the natural outdoor environment in both the visible and non-visible UV wavelengths. How- ever, because of legal concerns and the cost of pro- duction, this type of fixture never became widely available in the United States.Sunlight deficiency and the typical measures taken to compensate this deficiency may negatively affect one's sleep/wake cycles, which in turn may cause cardiovascular disorders (Edelstein et al., 2007) and cancer (Stevens et al., 2001). Electrical light- ing codes and standards with an emphasis on ener- gy efficiency often require insufficient footcandles during the day and too much light intensity at night for normal circadian function. Nurses and doctors assigned to shift work and patients who are continually exposed to illumination are unable to entrain (or align) with their 24-hour natural rhythms (Schernhammer et al., 2001). Our under- standing of sleep disorders was greatly enhanced by the 1998 discovery of melanopsin retinal ganglion cells, a type of photoreceptor in front of the eye's retina that provide signals to the suprachiasmatic nucleus (SCN), the brain's master clock (Hatori et al., 2010). These newfound cells project to many other brain regions as well, influencing countless aspects of human physiology.There is currently enough evidence to assist design- ers, architects, and engineers in selecting the prop- er type and sufficient quantity of light for different healthcare settings. It is critical in preventing errors such as misreading charts and medication labels, or a patient's vital signs. Knowing that a cool color temperature as in blueish white suppresses mel- atonin in humans and activates the brain means that this type of lighting should not be specified above a hospital patient's bed at night, but that it may benefit those with dementia in long-term care facilities by boosting their activity levels during daytime hours (Holtzman, 2010). …