(Issue: December 2017)
Senior Care in Lighting Design
Gundersen Tweeten Care Home in Spring Grove, Minn., contracted with Energy Performance Lighting (EPL) of Cottage Grove, Wisc., to install tunable white light in their care home. The director of Tweeten had read about case studies incorporating tunable white light that had a positive effect on the nursing home residents where it was installed.
EPL interviewed the staff to determine how the facility was utilized. This included meal time, wake time, bed time, when and where falls occurred and where residents spent most of their day. A walk-through assessment of the current lighting was completed and a plan was developed to upgrade the lighting to meet the requirements of the director while reducing energy consumption.
The lighting plan was developed utilizing guidelines provided by Dr. Steve Lockley of Harvard Medical School. It is essentially the same protocol that was developed for the International Space Station. It is based on specific color spectrums that are the most effective at suppressing melatonin during the day and the opposite during the night. This is what sets our circadian rhythm or internal time clock.
The lighting was installed throughout the entire building in December of 2016. A new ceiling was installed at the same time. The space by space lighting was designed as follows:
- Common areas: A programmable lighting system with a range of 3000K to 5000K with dimming capabilities.
- Rooms: LED T8 lamps installed in existing fixtures. The fixture is a standard hospital wall fixture. A 5000k lamp was used for up lighting during the day and 3000k for down lighting for evening use. Dimmable 2700K lamp at doorway entrance. Bathrooms had 3000k lighting.
- Kitchen areas and staff areas were all illuminated with 5000k LED lamps.
The design was cost effective, reduced energy consumption, and met the needs of improving the environment for the nursing home residents and staff. The residents spent most of their day in the common areas of the facility where the tunable lighting is located. A lighting protocol as follows, was developed based on how they spent their day:
- 7:00–10:00 a.m.: 5000 K at 350 lux
- 10:00 a.m.–4:00 p.m.: 5000 K 500 lux
- 4:00–8:00 p.m.: 4000 K 500 lux
- 8:00–10:00 p.m.: 83000 K 350 lux
- 10:00 p.m.–7:00 a.m.: 3000 K 50 lux only at the exits
The up-lighting in the resident rooms was turned on at 7:00 a.m. and turned off during dinner at approximately 4:30 p.m. The staff lighting remained on 24 hours/day.
Midwest Lighting Institute (MLI) reviewed the project to obtain measurements of before and after lighting installation to determine if there was an actual effect of the light. Six months after installation data was gathered and compared based on aggregate medical records.
Color Spectrum was measured with a spectrometer and calculated with the Lucas Tool to determine the Melonopic Lux or alertness effect of the light. Below on the left is the Spectral Power Distribution of the light in the common areas during the day. The blue spike is the area of the spectrum which is the most effective at increasing alertness. On the right is the SPD at night. Note the lack of blue content.
The results below are the most impressive for this lighting upgrade
- Falls dropped from 9.12 per 1000 resident days to 6.17 (32 percent reduction)
- Antianxiety meds dropped from 1.99 to 1.84 per 1000 patient days
- Antipsychotic meds dropped from 1.00 to 0.92 per 1000 patient days
- Staff surveys reported sundowners reduced by 38 percent
- Lighting energy consumption reduced by 63 percent
There is more to lighting than just energy efficiency. Light and health are intertwined. As more research demonstrates this relationship, lighting designers and maintenance professionals will have to know the science and apply it in their everyday work. Just based on reducing the number of falls, this lighting upgrade was paid for in less than six months.
This study was just one application of lighting in a nursing home. There are many more types of studies being conducted as you read this. They include improving student performance, reducing the medical error rate, reducing harmful microbials in health care environments, all with visible light. There is potentially much more that we do not even know about and it is yet to be discovered. Think of the people who can be helped with just light. This is all on top of reducing energy consumption by 60–70 percent.
There are some who will ignore this relationship, others will start investigating and the leaders will begin applying the physiological principles of light and health. As more research evolves, there will ultimately be finger pointing because somebody installed the wrong color of light and an error was made and damage occurred or a life was lost. As a lighting professional, we encourage you avoid this and begin learning about the science of light and human response. It will help your client, achieve greater energy consumption than just changing lights and protect you from any finger pointing..