When planning lighting, illuminance is a critical technical value. But what does the value mean, and what level of lighting do you need at your workplace? The following article is supposed to explain this and help you to choose the right lighting solution.
What is illuminance?
We specify an artificial light source’s illuminance in the unit lux (lx) and use them to determine how much light hits a given surface. There is often confusion between the units lumen and lux. Therefore, we would like to explain the difference briefly: The unit lumen (lm) only indicates how much light the light source emits in all directions. In contrast, the illuminance (unit lux) indicates how much light hits the work area, i.e. to a specific place. As a result, we perceive brightness as very bright at a high lux value. Depending on the light source’s distance from the work surface, this value is influenced and results in a low lux value at a considerable distance and a high lux value at a small space.
Figure 1: Difference between lux and lumen of an artificial light source
Which illuminance for which application?
Low illuminance at the workplace can lead to rapid eye fatigue and thus to poor work results. Therefore, it is necessary to determine the illuminance differentiated according to the field of application. Since there are many individual visual tasks in our everyday working lives, the minimum illuminance requirements for all application areas have been defined in the work guideline Din 12464-1 “Light and lighting – Lighting of workplaces”. In practice, however, experience with customers has shown that much higher illuminance levels than the minimum requirements defined in the standard are needed in some cases to create the desired visual conditions.
Therefore, we would like to give you our recommendations based on our customer experience for the various application areas.
For dental technician areas, the DIN standard recommends 1000 – 1500 lux. However, based on experience with many of our dental technology customers, we recommend an illuminance of at least 2800 lx – 3300 lx.
Our RMD recommendations for the dental technician:
Like the dental technician, we recommend an illuminance of at least 2800-3300 lx for watchmakers.
Our RMD recommendations for watchmakers:
For a goldsmith’s application area, we recommend an illuminance of 2800-3300 lx.
Our RMD recommendations for goldsmiths:
Illuminance levels of 1000-3300 lux are suitable for the workplace of modellers. But even here, a higher illuminance should be preferred for precision work.
Our RMD recommendations for model makers:
Depending on the task in your workshop, the illuminance can vary from values between 200-300 lux (welding, repair work on engines), 1000 lux (painting) or 1500 lux (final inspection, quality testing). So we recommend preferring higher illuminance levels to provide sufficient light for the visual task at hand.
Our RMD recommendations for the workshop:
We advise fly tyers to use a light with an illuminance of at least 1500 lux so that the flies’ colours to be tied are visible.
Our RMD recommendations for fly tyers:
Articulated-, magnifying-, flexarm- or pendant lamps?
It is up to the user and the type of application. All variants can produce identical illuminance levels. However, if you prefer to have the table free, you should use a pendant luminaire. If you want to have the luminaire head close to the work object because this is appropriate to the individual working method or the visual task requires it, you should always take an articulated lamp flexible arm lamp or, if magnification of the object is required, a magnifying lamp! If lighting is needed for the entire room and the work surface, an interaction between a pendant and table lamp can provide an even better lighting atmosphere.
Our most common lights in the categories of pendant-, articulated-, magnifier- and flex arm lamps are…