What is PD CEN/TR 16791- Irradiance for eye-mediated non-image-forming effects about?
PD CEN/TR 16791 is a safety standard on quantifying irradiance for eye-mediated non-image-forming effects of light in humans.
PD CEN/TR 16791 proposes metrics that can be used to evaluate and compare lighting conditions with respect to their potential to achieve non-image-forming, eye-mediated effects of light in human beings.
PD CEN/TR 16791 applies to visible optic radiation in the wavelength range from 380 nm to 780 nm.
Note 1: PD CEN/TR 16791 does not give information for lighting applications.
Note 2: PD CEN/TR 16791 does not address health safety issues such as resulting from flicker, photobiological safety, or the effects of non-visible optical radiation (ultraviolet and infrared radiation.
Who is PD CEN/TR 16791- Irradiance for eye-mediated non-image-forming effects for?
PD CEN/TR 16791 on quantifying irradiance for eye-mediated non-image-forming effects of light in humans is relevant to:
- Testing authorities
- Medical personnel
- Eye specialists
Why should you use PD CEN/TR 16791- Irradiance for eye-mediated non-image-forming effects?
There is strong scientific evidence that light is not only essential for vision but also elicits important biological, non-image-forming effects that are highly relevant for human performance and well-being. The non-image-forming effects can be either eye or skin-mediated (e.g., vitamin D production, skin cancer, or solar dermatitis).
PD CEN/TR 16791 focuses on the eye-mediated non-image-forming effects. Depending on the time of light exposure, spectral power distribution, duration of exposure, and individual parameters like circadian phase, light history, and others, light can cause suppression of the nocturnal release of melatonin, increase heart rate as well as alertness and affect thermoregulation, or the electroencephalogram spectrum. Light is the main synchronizer of the human biological clock. It can shift the phase of the circadian system and determine the timing of the sleep/wake cycle. The above-mentioned biological effects of light are elicited by stimulation of ocular photoreceptors. The actual biological effect of ocular exposure to light depends on the relative response of all photoreceptors and there is good evidence for synergistic responses between the receptors. For a deeper understanding of how a simulation of the photoreceptors leads to a desirable or undesirable biological effect, the light is characterized in a way to quantify the input to each of the five known photoreceptors.
PD CEN/TR 16791 assists with the biological non-visual effects of light which have a direct impact on human performance and well-being with large implications for architecture, indoor design, and lighting as well as for social- and work schedules. PD CEN/TR 16791 contains the input of experts that, at the time of writing, also have contributed to the Draft International Standard in preparation by CIE JTC 9 "CIE system for metrology of ipRGC influenced light response". PD CEN/TR 16791 is entirely informative in nature.
Overall, PD CEN/TR 16791 is useful as it explains the importance of darkness, and the daily pattern of light and dark, particularly around and during periods of sleep. PD CEN/TR 16791 helps in analysing the involvement of different photoreceptors and helps to understand how such outcomes with impact on human health are provoked.
