The lighting at work premises often impacts upon the safety and health of workers at work. In principle, the European legal framework makes no provision for standards in this area. Nevertheless, standards governing lighting at work premises have been and continue to be developed. KAN's view is that the German national foreword of such standards must state that national provisions governing lighting at work premises exist that extend beyond the scope of the standard. References at this point to the German Ordinance on Workplaces and to relevant state rules and regulations and those of the German Social Accident Insurance Institutions assist the user of the standard in observing the binding regulations.
Non-visual effects of light
Besides enabling human beings to see, light also has non-visual effects upon the human body. Non-visual effects of light influence human physiology, mood and behaviour. Light can for example briefly raise attentiveness, and may also influence the human biological clock and thus also the circadian (i.e. daily) rhythm.
Besides being exerted by daylight, these non-visual effects can also be produced by special artificial lighting. Daylight, however, dictates the natural rhythm for each individual's inner clock. Artificial lighting may have similarities to daylight but is not a substitute for it in every respect.
Non-visual effects of light are dependent upon a number of factors:
- Spectral composition
- Point in time of exposure to the light
The right light at the right time can stabilize the human biological clock and thereby improve sleep patterns. A study conducted by the Federal Institute for Occupational Safety and Health (BAuA) for example has shown that in the morning, lighting enriched by a blue component not only has an acutely stimulating effect, but also has the potential to compensate for subsequent disturbances of the body's biological clock. A disturbance of the biological clock can for example be caused by exposure of an individual to the same light enriched by a blue component shortly before they go to bed: the light has a stimulating effect and may therefore keep the individual awake. The wrong light at the wrong time can increase tiredness during the day, sleep impairments, and thereby the accident risk.
New types of lighting system are available on the market that exploit these non-visual effects of light. The intentional triggering of visual, emotional and non-visual effects of artificial light is currently described as human-centric lighting (HCL; defined by the ZVEI), particularly in the lighting industry. A further term in use is that of artificial, biologically effective lighting.
Is this topic relevant to occupational safety and health?
Light has a continual effect at every workplace. The non-visual effects of light present both opportunities and risks. Should lighting systems be used inappropriately, the non-visual effects may lead to health impairments. In particular, the high blue component of highly efficient lamps may give rise to unintended stimulation of the workers.
Early consideration is therefore to be given to safety and health during the planning of lighting installations; this includes consideration for the respective opportunities and risks presented by different lighting scenarios.
In 2015, KAN published a position paper on the subject of non-visual effects in standardization. Since further observations have been made and agreements reached in discussions between the stakeholders since the position paper was published, it was updated in 2017. The position paper contains information from the occupational safety and health community on standardization, research, regulation and application of the new technology. The following documents were published after 2017:
- KAN-literature review "Gesicherte arbeitsschutzrelevante Erkenntnisse über die nichtvisuelle Wirkung von Licht auf den Menschen" (Validated OSH-related findings concerning the non-visual effect of light upon human beings) (abstract in English)
- the DGUV InformationDGUV Information 215-220 Nichtvisuelle Wirkungen von Licht auf den Menschen (only in German)
- and the „Empfehlung des Ausschusses für Arbeitsstätten (ASTA) – Künstliche biologisch wirksame Beleuchtung in Arbeitsstätten“ (only in German; recommendations of the ASTA which is a governmental committee), saying: use artificial lighting with colour < 4100 K during the night; continuous lighting of cold light with high illuminance levels should be avoided
We are currently adapting the KAN position paper from 2017 to these new developments.
BAuA information material
BAuA study: "Mental health in the world of work: lighting" (in German)
BAuA study: "Circadian effects of AmI-based lighting systems: Effects of circadian desynchronization" (in German)