calendarJul 23, 2020
clock Reading time: 5 minutes

What does photobiological safety mean?

Does a high proportion of blue light in LEDs endanger our health?

Many people are unsettled by negative headlines in connection with the threat to our health from LEDs and topics such as so-called photobiological safety. Frequently asked questions that arise particularly in relation to the right workplace light include:

    • Does LED light with a high proportion of blue light rob you of sleep?
    • Does LED light mess up the internal clock?

Is this uncertainty justified? Do LED workplace lights really pose a hazard to the eye? In order to pursue these questions, it is necessary to clarify from the ground up what effects blue light has on our body and how the risk of exposure to blue light from artificial light sources is to be classified.

Our inner clock is controlled by blue components in the LED light spectrum with a wavelength of around 480 nanometers. There are photoreceptors in the eye that specifically collect light of this wavelength. Especially in sunlight, such blue tones are strongly present around noon. bright, bluish and strong light brakes in our body the Release of the sleep hormone melatonin. So if we have lighting with a high proportion of blue light during the day, this increases activity and encourages concentrated work. In the evening, on the other hand, these blue tones are missing in natural daylight, the light appears reddish and the melatonin levels increases continuously, making us tired. Therefore should in the evening to lighting with high illuminance levels and high proportion of blue light should be avoided in order to avoid sleep disturbances. So while a high proportion of blue light is desirable during the day, it is certainly undesirable at night because it causes sleep disorders and can therefore be harmful to health. The use of light with lower Color temperature around 3000 Kelvin is therefore recommended.

The photobiological safety of light and LED workplace lights in accordance with DIN-EN-62471

Blue light hazard is the potential risk of photochemical damage to the retina caused by high-energy, blue visible light. It preferably occurs in Wave range between 400 nm and 500 nm on. This light can penetrate the cornea and reach the retina. As a result, receptors can irreversible damage to take.

In the discussion, it is often claimed that a high proportion of blue light in daylight-white LEDs endangers the retina and can therefore be harmful to health. But are LED workplace lights really a hazard to the eye?

A direct look at the sun (high proportion of blue light, extremely high luminance) can be harmful even with brief exposure. On the other hand, looking into the blue sky (very high proportion of blue light, low luminance) is possible without hesitation. The blue light component alone is therefore not responsible for possible damage to the eye! Very high luminance levels and the duration of exposure must also be taken into account.

If LED workplace lights are used as intended, there is no risk to the eyes. The lamp head and articulated arm technology are designed in such a way that a direct view of the LED modules is avoided and the user is therefore not dazzled. Furthermore, the LED modules are covered by plastic discs, so that even a quick glance at the light is harmless. But which user already does this? Nevertheless, there are differences in the risk assessment of LED workplace lights. The risk of blue light exposure can be assessed on the basis of the European standard DIN-EN-62471 (in Germany DIN EN 62471). The light sources are classified according to different hazards, e.g photochemical retinal hazard (blue light hazard) assessed and divided into risk groups. The standard classifies the photobiological safety of light sources into the following risk groups (RG):

    • RG 0 "exempt" Are safe under all circumstances. No risk to the eye, even with permanent
      Looking towards the light source.
    • RG 1 "low risk" Low risk You can look into the light source for several minutes without risk
    • RG 2 "mod risk" Medium risk. You can look into the light source for a few seconds without any risk
    • RG 3 "high risk" Damage to the eye possible even with brief exposure

Note: The sun would fall into the highest risk group 3 (RG3).

All our RMD workplace lights belong in terms of their photobiological safety risk groups 0 and are certified by Photometrik GmbH. They therefore fall into the group of artificial light sources with the highest photobiological safety. A health hazard, a disturbance of sleep and damage to the retina can therefore be ruled out. You can view the measurement report and the expert opinion below.