Light / Illuminance (lx)
air-Q with a light/illuminance sensor
Description of the light / lighting:
Light allows humans to perceive their surroundings with their eyes. However, too much or too little light distorts our sensory perception. This applies to both daylight and artificial lighting. In this context, the intensity and wavelength of light are key factors in determining our tolerance for it.
Various regulations specify the intensity and wavelengths at which artificial light sources must emit light. For example, emergency lighting along evacuation routes must have an intensity of at least 1 lux.
By way of comparison: this is roughly the same amount of light emitted by a candle from a distance of about 1 meter. Typical household lighting, on the other hand, ranges from 100 to 300 lx, while that of a modern operating room is 160,000 lx.
The human eye perceives radiation in a wavelength range of approximately 380 to 780 nanometers (nm). It functions most effectively in daylight, with wavelengths around 555 nm. The range of luminance within which it can perceive contrast lies between10−4cd/m²and10⁴cd/m².
Based on these values, the optimal illuminance for workstations is derived: it should be, on average, at least 500 lx.
Lighting limits:
For workplaces in Germany, there are recommendations regarding the type and direction of lighting and the corresponding measures to protect the eyes from fatigue.
In its document “Technical Rules for Workplaces,” the Federal Institute for Occupational Safety and Health (BAuA) sets forth the following minimum values in May 2023 regarding “lighting and visual contact”:
| Area of Activity / Use of Space | Minimum illuminance value E (lx) |
| Precision work, e.g., sanding decorative elements, color checks, assembly work | 1000 lx |
| Writing, reading, data processing | 500 lx |
| Files | 200 lx |
| Break rooms, waiting rooms, locker rooms | 200 lx |
Consequences of too much or too little light:
Unfavorable lighting conditions can cause problems with concentration, headaches, and eye strain, and can even lead to impaired perception and reaction times. In poorly lit environments, people also often adopt poor posture to compensate for visual deficits. Over time, this can lead to strain and injury, resulting in an increase in sick leave.
To protect yourself from the short- and long-term effects of insufficient lighting, it is recommended that you ensure the lighting is at an appropriate level.
Origin of Light
Light is generated by converting chemical energy through combustion or fusion processes, or by discharging electrical energy. It can also be released through the conversion of electrical energy. Both processes occur naturally (fire, lightning, the sun) and are generated by humans (light bulbs, LEDs).
Sensor used:
The light sensor measures light intensity by detecting the brightness of incident light and converting it into a digital signal. It takes into account only the spectrum of light perceptible to the human eye and ignores infrared and ultraviolet radiation.
Measure light:
Measure the light levels and indoor air pollutants in your office or home in real time with the air-Q air analyzer, available for order here.
More measured values / sensors
