The Lighting Research Center (LRC) at Rensselaer Polytechnic Institute (RPI) is one of the world's leading centers for lighting research and education. Professor of Architecture at RPI and Director of the LRC, Dr. Mariana Figueiro has been pioneering research on Light and Health and is specifically known for her work on the effects of light on human health, circadian photobiology, and lighting for older adults. Through the LRC and with a grant from the National Institute of Occupational Safety and Health (NIOSH), she has created a series of short videos on the science of lighting for human health.
In this series of 9 videos, Dr. Mariana Figueiro gives a brief overview of human circadian rhythms - explaining their importance and the need for staying entrained with lighting.
LRC Video 1 - Circadian Rhythms
A brief overview of human circadian rhythms - explaining their importance and how light exposures help synchronize our internal clocks to the local time.
(Video length 2:56 minutes)
LRC Video 2 - Circadian Stimulus
An overview of circadian stimulus (CS), a metric developed at the Lighting Research Center to quantify the extent to which lighting impacts the human circadian system.
Explains the role that light levels and spectrum play in CS
Impact of other qualities of lighting
Other metrics not recommended due to inability to predict light's effect on the circadian system
(Video length 5:35 minutes)
LRC Video 3 - Circadian Stimulus Calculator
The LRC has developed a calculator to determine the amount of circadian stimulus in circadian light. This video explains the LRC's circadian stimulus calculator and how to calculate CS levels provided by one or more light sources in a 3-step process.
Select light source(s)
Determine light level at the eye
Interpret results
The circadian stimulus calculator is available online at:
LRC Video 4 - Delivery & Control of Circadian Stimulus
Overview of techniques to deliver and control circadian stimulus at various times of day.
(Video length 3:33 minutes)
LRC Video 5 - Lighting For Older Adults
Aging can result in deterioration of vision, a decreased sense of balance, and sleep disruption. This video explains how lighting can be used to mitigate these isues.
(Video length 3:52 minutes)
LRC Video 6 - Lighting For Shift Workers
Shift work involving night and early morning shifts have been linked to health problems and decreased performance. This is likely to be linked to disruption in circadian rhythms due to staying awake through the night when our biological clocks require us to sleep. Dr. Mariana Figueiro discusses lighting strategies to provide a solution.
(Video length 3:19 minutes)
LRC Video 7 - Lighting For Adolescents
Due to adolescents' circadian rhythms, they tend to fall asleep and wake up naturally at later times than societal norms. Early starting times at middle schools and high schools can lead to poor performance, day time sleepiness and many other issues. Dr. Mariana Figueiro discusses how controlling lighting can help teens get more sleep.
(Video length 3:22 minutes)
LRC Video 8 - Lighting For Office Workers
Dr. Mariana Figueiro discusses the challenges for office workers who are not exposed to sufficient circadian stimulus and techniques to help them.
(Video length 2:12 minutes)
LRC Video 9 - Future Directions In Lighting For Health
We're currently seeing the lighting industry shift from lighting for vision and energy efficiency to an approach that considers human centric lighting. The video explores the future direction for using lighting to improve health and well-being.
