The adoption of electronic light has changed the ‘circadian rhythm’ of our bodies, which controls key features such as sleep-wake behaviour and hormone secretion. This disturbs the 24-hour sleep cycle we should be operating on for optimal health and happiness.
Recent studies have shown we now spend close to 90% of our lives indoors, a historically unprecedented amount. This means we are simply not getting enough natural sunlight.
‘Human-centric lighting’ is a solution that works to maintain a natural light cycle indoors, no matter where you spend the majority of your day.
In this article, we will discuss the practicalities and benefits of a tailored human-centric lighting scheme - especially in workplace environments.
Human-centric lighting: what is it exactly?Human-centric lighting solutions can support the human circadian rhythm and enhance concentration. They also prevent sleeping disorders and improve our overall mental well-being.
So how do they work exactly? Recent innovations in lighting technology (in particular with LEDs) has meant that ‘tuneable’ white light can be achieved in an energy-efficient manner. This light is then managed with advanced control systems.
New, smart, connected lighting systems create endless possibilities with better user control. For instance, the SkyLux works its magic by replicating a natural 24-hour day cycle. It has a panel which realistically depicts scenes of sky, clouds and sunshine.
The main control will be the level of brightness intensity, which is scaled all the way from 0 (which gives the effect of a cloudy day) to 100 (which exudes the light of an intensely sunny day).
This means that the owner of this advanced lighting system can choose what type of weather is simulated in a building.
Practical considerations for human-centric lighting schemes
The components that make up the luminaire must guarantee an adequate level of performance. First and foremost, they must pass tests to ensure they meet all electrical and mechanical test requirements. They should also be tested to make certain that ‘LED flicker’ is kept to an absolute minimum.
LED flicker originates from a mismatch of components - when the LED module, driver and control system are not working in harmony. This mismatch causes a flickering light which has damaging consequences.
If left unchecked, flicker can result in chronic discomforts such as eye-strain and headaches. In workplaces, this is shown to lead to an increase in absenteeism. Manufacturers must guarantee that LED flicker is minimised to avoid this problem.
Light distributionYou must consider that not all luminaires are appropriate for human-centric lighting systems and certain design criteria must be satisfied. Many of the existing general-purpose lighting fixtures in commercial settings cannot meet these design criteria.
The distribution of light from a luminaire in a human-centric system must not create glare. Glare is a serious problem at workplaces as it can cause long-term health problems.
Excessive brightness entering the eye from intense luminaires reflecting from working equipment (such as screens) prevent workers from being able to read data and reduces productivity.
However, if you arrange a system of quality luminaires in a well-spaced pattern there will be minimal amounts of glare caused. Furthermore, the optimal amount of light needed to aid the natural circadian rhythm will be achieved.
The advantages of a human-centric lighting systemThe sheer quality of LED light has improved leaps and bounds over the last few years. New developments in LED colour schemes mean that we can now match the colour output that is created by the natural light spectrum.
As previously mentioned concerning the SkyLux, this means we can accurately simulate weather conditions that are occurring halfway across the world. Human-centric lighting schemes are designed using ultra-high colour rendering LEDs, which consistently depict a colour accuracy of over 95 percent.
This increase in the quality of colour rendering will reap health benefits. Currently, there are efforts to move colour accuracy performance even further, using ‘sunlight’ criteria for LEDs.
These LED modules are designed to mimic the spectrum of sunlight. In doing this, LED manufacturers are seeking to reduce the ‘blue spikes’ in the LED spectrum that are considered poor for our health.
Lighting controlWith human-centric lighting comes dynamic lighting control. The latest thinking from designers is that the core lighting should be set according to a fixed scheme, which will fit a general ‘working pattern’, convenient to employees.
Health benefitsAs mentioned before, the presence of blue wavelengths is negative for our health. It suppresses the effect of the pineal gland, which ‘tricks’ the brain into thinking that it’s safe for us to carry on working, when we should be preparing for a good night’s sleep.
Human-centric lighting has the ability to reduce blue content in white light by shifting the ambient colour spectrum from ‘daylight’ to a comfortable warm light as we come to the end of the day.
Lighting levels (illuminance) are also adjustable across the working day so they can replicate external conditions.
As evidenced by the pioneering SkyLux, human-centric lighting is really making waves in the lighting industry. Hopefully, in the near future, bespoke lighting will be the norm in all modern workplaces.