Wide awake

Lighting concept at the Scharnhausen Technology Plant

Light is very important for the human organism. This is especially noticeable during the dark winter months when there is less daylight, which often leads to depressed moods. Even a long working day under artificial light can be tiring. The less daylight there is, the more the light levels drop at the workplace and hence the ability to concentrate. Scientists have come up with solutions that are now being applied in practice.

The colour of the light plays an important role for people's day–night rhythm. The retina of the eye contains so-called photosensitive ganglion cells which transmit the information absorbed by the eye to the brain. They are particularly good at absorbing light in the blue area of the visible spectrum. Blue light leads to a reduction in the production of the sleep hormone melatonin, which means we stay awake longer and can concentrate better. Red light, on the other hand, leads to the body preparing itself for the rest phase and sleep.

Lighting influences biorhythms

How these findings can help in everyday work is shown by the example of the Festo Technology Plant in Ostfildern-Scharnhausen. A health-promoting lighting concept was put into place in cooperation with the Fraunhofer Institute for Industrial Engineering. It is based on natural sunlight, which, over the course of a day, shifts from a cool blue to a warm, red light.

Production employees who work in shifts can thus have the right light intensity that corresponds to their natural biorhythms for the time of day. Back at home after a late shift, workers will find it easier to sleep thanks to the increase in red light towards the end of the day.

Brightness helps

Besides the colour of light, the brightness can also have effects on the human organism. Dr Max Kaplan, president of the Bavarian State Medical Association and former GP, deals with this phenomenon. According to him, a consistent level of brightness has a positive effect on concentration at the workplace. He therefore had around 700 LED pendant lights installed in the Munich offices of the State Medical Association. These provide a consistent brightness of 500 lux to all workstations and, at the same time, consume much less energy than conventional lights.

The principle is simple: as soon as it gets brighter outside, the LED lights will dim; when it gets darker, the control system turns their brightness up.