Can you imagine a life without sunsets? Twenty-four hours of daylight? Probably not.

But constant light and unnatural lighting patterns are relatively common in hospitals and group-living centers. These situations disrupt sleep patterns, cause disorientation and throw off basic bodily function, and now a team of Drexel researchers is working on a solution that brings the benefits of natural light inside with the flip of a switch.

Drexel’s Don McEachron and Eugenia Ellis note that while hospitals and living centers are designed to keep patients in a safe, comfortable, sterile environment, a consideration that sometimes goes by the wayside is residents’ exposure to natural light. Ambient, artificial light in these facilities allows health care workers to conduct their jobs and monitor residents day and night. But McEachron and Ellis believe the residents could experience a much better quality of life and benefit from the improved health that comes with exposure to a regular daylight cycle.

“To keep organisms aligned both inside and out, circadian rhythms—using what is sometimes called a ‘biological clock’—synchronize to the daily cycle of light and darkness. In artificial or built environments, constant or unpredictable lighting can cause a failure of alignment and contribute to a loss of temporal health. Humans that are ‘out of tune’ are more susceptible to a variety of problems, issues and disorders,” McEachron says.

“In artificial or built environments, constant or unpredictable lighting can cause a failure of alignment and contribute to a loss of temporal health.”
Don McEachron, research professor

Their solution is a two-foot-square LED light fixture that can be adjusted to mimic the changing color and intensity of natural sunlight, thus simulating a natural day-night light cycle inside the health
care facility.

Ellis, who holds appointments in both the Westphal College of Media Arts & Design’s Architecture & Interiors Department and the College of Engineering’s Civil, Architectural and Environmental Engineering Department, is designing the light. McEachron, a research professor and associate director in the School of Biomedical Engineering, Science and Health Systems, is providing the circadian know-how to tune them so they are in sync with the natural light.

The “daylight” fixtures will get their first trial run at the St. Francis Country Day Home, a senior living facility in Delaware County. Ellis is currently finalizing a prototype and hopes to have the lights installed at St. Francis this summer.

A prototype of the daylight-matching luminaire is being tested in a lab in Drexel’s College of Engineering.

McEachron will work with Elizabeth Gonzalez, a professor in the College of Nursing and Health Professions, to conduct a comparative study over the course of several months to monitor the effect of the lights on the patients’ sleep habits, energy levels and overall quality of life.

If successful, the group hopes to make these lights available for retrofitting health care facilities so that patients can experience a normal light-dark cycle even if it’s not coming from the sun.