The environmental impact of the new version of the Interior Lighting European Norm in Lighting and Circadian Design

The new version of the European Standard of Interior Lighting (EN 12464-1) considers LED technology for energy saving and minimizing environmental impact by giving new criteria for quantitative and qualitative lighting, including those that concern the “non-image-forming effects” (NIF) of light. In addition, it takes into account normal aging as an assumption for proposing increased light levels in indoor workplaces. In real applications, this seems to create lighting conditions that do not fully support human well-being based on the criterion of WELL Building Standard v2 (2021) for Circadian Lighting Design. Therefore, in offices, it is proposed to increase the light levels by at least one step from the minimum provided by the EN Standard. In order to examine this hypothesis, a typical office space is examined. In addition to the main requirements, the Mean Ambient Illuminance (Ēamb) and the Mean Room Surface Luminous Exitance (Mrs) are calculated according to the EN Standard but also the Equivalent Melanopic Lux (EML) and the Melanopic Equivalent Daylight Illuminance (M-EDI) as proposed by the WELL Standard. The comparison between EN 12464-1 and Well Standard has shown that the qualitative lighting design criteria are stricter in WELL than in EN Standard.