Introduction
A method for risk assessment in the field of visual ergonomics is under development. Insufficient visual ability can lead to increased workload and contribute to eyestrain and musculoskeletal discomfort. Although the relation between eyestrain and musculoskeletal discomfort is not fully understood, studies have shown that straining the eyes increases the musculoskeletal activity in the neck and shoulders (trapezius); associations between visually demanding work, eye problems, headaches and/or muscle problems have also been found (Aarås et al., 2001; IESNA, 2011; Zetterlund et al., 2009; Zetterberg et al., 2013; Toomingas et al., 2013; Richter et al., 2011; Richter et al., 2015). Problems due to insufficient visual ergonomics not only exist in computer intensive work, but in other professions as well, such as surgeons and postal workers (Hemphälä et al., 2011; Hemphälä et al.,2012).
The aim of this project is to develop a practical, easy-to-use, and time efficient risk assessment method for visual ergonomics. With this method, risk factors in the visual environment can be detected, and interventions implemented to reduce the prevalence of symptoms related to poor visual ergonomics among workers.
Methods
A first version of the risk assessment method has already been developed. In the spring of 2015, 27 ergonomists were taught visual ergonomics and introduced to the method. After the course, each ergonomist used the method to assess 8-10 workplaces, providing data and practical experiences from approximately 250 risk assessments. These data will be used to further develop and improve the method. During the fall of 2015 and spring of 2016, two other groups, each consisting of 30 ergonomists, will be trained in using the revised version of the risk assessment method in approximately 10 workplaces each. Data from these assessments will be used to test the validity and reliability of the method.
Results
The first version of the risk assessment method for visual ergonomics will be presented at NES 2015 together with the results from the approximately 250 risk assessments made by the first group of ergonomists. So far, the factors included in the method are objective measurements of illuminance, luminance contrast, illuminance uniformity values, size of work object, visual angle; expert assessment of the risk for glare; and subjective ratings of visual ability, eyestrain and musculoskeletal discomfort. Some tendencies have been found of correlations between an objectively-rated high risk for glare and eyestrain/headache, as well as between a high contrast glare/luminance ratio and eyestrain.
Conclusion
Several factors in the visual environment contribute to wellbeing and the level of performance. In this risk assessment method for visual ergonomics, ergonomists have been trained to evaluate, for example, the risk for glare, as one of the major risks. The risk assessment method presented will be discussed in relation to its usefulness in the prevention of discomfort and work-related disorders at workplaces.
NEHF , 2015. p. B1-1-
Nordic Ergonomics Society 47th Annual Conference (NES 2015), 1-4 November 2015, Lillehammer, Norway