Summary
This expert consensus paper provides actionable, time-of-day-specific indoor lighting recommendations expressed in melanopic equivalent daylight illuminance (melanopic EDI), giving lighting designers a standardized, biologically grounded framework to optimize health and performance. The recommendations address daytime, evening, and night-time exposures separately to maximize circadian entrainment, sleep quality, and cognitive function while minimizing unwanted circadian disruption.
Key Findings
- Recommends ≥250 melanopic EDI lux during the daytime to robustly stimulate alertness and support circadian entrainment
- Recommends ≤10 melanopic EDI lux in the evening/night to minimize circadian disruption and melatonin suppression
- Introduces melanopic equivalent daylight (D65) illuminance as the SI-compliant metric for characterizing non-visual (ipRGC-mediated) light effects
- Comprehensive sensitivity analysis of human non-visual responses underpins the quantitative thresholds provided
Categories
The Science of Light: Establishes SI-compliant melanopic equivalent daylight (D65) illuminance as the standard metric for quantifying non-visual light effects, with expert consensus recommendations.
Sleep & Circadian Health: Recommendations directly target circadian rhythm entrainment and sleep quality through time-of-day-specific light exposure guidance.
Workplace Performance: Recommendations address daytime indoor light exposure to support alertness, cognitive function, and neuroendocrine performance.
Author(s)
T Brown, G Brainard, C Cajochen, C Czeisler, J Hanifin
Publication Year
2020
Number of Citations
51
Related Publications
The Science of Light
- Phototransduction by retinal ganglion cells that set the circadian clock
- Color appearance models
- The mammalian circadian timing system: organization and coordination of central and peripheral clocks
- Diminished pupillary light reflex at high irradiances in melanopsin-knockout mice
- Melanopsin is required for non-image-forming photic responses in blind mice
Sleep & Circadian Health
- Phototransduction by retinal ganglion cells that set the circadian clock
- The mammalian circadian timing system: organization and coordination of central and peripheral clocks
- The two‐process model of sleep regulation: a reappraisal
- Melanopsin is required for non-image-forming photic responses in blind mice
- Strange vision: ganglion cells as circadian photoreceptors
Workplace Performance
- Acute alerting effects of light: A systematic literature review
- Effects of artificial dawn and morning blue light on daytime cognitive performance, well-being, cortisol and melatonin levels
- Can light make us bright? Effects of light on cognition and sleep
- Kruithof's rule revisited using LED illumination
- Shining light on memory: Effects of bright light on working memory performance