Ergonomics

The right light in the right place. That is the ergonomics of light. But what defines the right light? To answer this question we must understand how light affects the human eye. Only by doing so can we respect the principles that govern our visual world and consequently create a visual harmony that ensures comfort and acuity.

The majority of our understanding of these principles is laid down in the European standard EN 12464-1 for interior workspaces. By following these standards, and where appropriate surpassing them, lighting designers can choose exactly the right light source, optical system and light distribution for each individual space. In retail applications, this covers all lighting parameters: colour rendering index, glare prevention, illumination level, lighting uniformity and harmonious distribution of brightness. Each individual parameter must be viewed as part of a holistic whole, ensuring the perfect for both customers and employees.

Colour Rendering Index

Colour is possibly the most important visual parameter in retail environments. It determines our perception of goods , informs our decisions to buy and defines the identity of a store. Colour, however, does not exist without light, thus what light we use in retail environments in absolutely key.

In order to define the CRI of a given light source it must be compared to a neutral control light source, most commonly daylight. Both the control and test light source must have the same CCT properties for the comparison to be accurate, as CCT is one of the key determiners of CRI. The more accurate the colour rendition of a light source, the higher its CRI value, with daylight having CRI= 100. To assess colour rendition, fifteen test colours are compared, each receiving an individual rating with the average of the first eight referred to as the Ra value, the standard expression of CRI used throughout the industry.