RISKS IN THE VISUAL ENVIRONMENT SUCH AS GLARE, ILLUMINANCE AND LUMINANCE RATIO - RISK ASSESSMENTS MADE WITH VISUAL ERGONOMICS RISK ASSESSMENT METHOD, VERAM– A DESCRIPTIVE PAPER

The visual environment has an impact on subjective strain and headaches. A visual ergonomics risk assessment method, VERAM, was used on 217 workplaces, and consists of both of a subjective questionnaire and an objective risk assessment, the latter risks are presented in this paper. The risk for daylight was assessed to be yellow (moderate risk) or red (high risk) at 53% of the workplaces and the risk for glare was yellow or red at 66%. The assessment of the lighting design showed a yellow or red risk at 44% of the workplaces and the illuminance was assessed to be insufficient at 49% of the workplaces. Flicker or TLM (temporal light modulation) was assessed to be a problem among 33%. These results show that the design of the visual environment is in most cases not performed in a satisfying way. The visual environment is essential to increase wellbeing, health and performance.

Quantifying biologically essential aspects of environmental light

Quantifying and comparing light environments are crucial for interior lighting, architecture and visual ergonomics. Yet, current methods only catch a small subset of the parameters that constitute a light environment, and rarely account for the light that reaches the eye. Here, we describe a new method, the environmental light field (ELF) method, which quantifies all essential features that characterize a light environment, including important aspects that have previously been overlooked. The ELF method uses a calibrated digital image sensor with wide-angle optics to record the radiances that would reach the eyes of people in the environment. As a function of elevation angle, it quantifies the absolute photon flux, its spectral composition in red–green–blue resolution as well as its variation (contrast-span). Together these values provide a complete description of the factors that characterize a light environment. The ELF method thus offers a powerful and convenient tool for the assessment and comparison of light environments. We also present a graphic standard for easy comparison of light environments, and show that different natural and artificial environments have characteristic distributions of light.