Illuminance

The illuminance is a calculated value that says how light an entire room or a certain area is in it. For some areas, such as jobs and manufacturing facilities, the minimum requirements for those in DIN EN 12464-1 are set. The illuminance is given in Lux (LX) and abbreviated with the letter E. It indicates the luminous flux, which meets a certain area from a light source.

You get a lux when the luminous flux of a lumen illuminates exactly one square meter. This is measured with a luxmeter on horizontal and vertical surfaces.

Overall, however, the illuminance does not describe the exact brightness impression of a room, since it depends on several factors. Above all, the reflection properties of the areas and walls also play an important role here, for example, since a white space with the same illuminance looks much brighter than a dark painter.

In addition, the light distribution of a lamp is not absolutely even, which is why norms usually indicate the so -called medium illumination. This takes into account the unevenness arithmetically and can therefore be used as a standard.

Typical illuminance are:

• Sunlight: 100,000 lux
• Summer shade: 10,000 lux
• Workplace lighting: 500 lux
• Traffic zone lighting: 100 lux
• Street lighting: 10 lux
• Candle about 1 meter away: 1 lux