Lighting, performance and age variation.
NIOSH 1975 Mar; :37-42
The relationship between lighting, performance and aging was discussed with emphasis on the ability of the eye to use the light energy available. The diameter of the pupil decreases according to age, with subsequent reduction in the light transmitted by the lens. To achieve the same retinal performance, the old eye requires more light. This problem usually arises only under threshold conditions when the amount of light available is small. According to available evidence, the eye of a 60 year old individual requires about three times the amount of light needed by the eye of a 20 year old person, under threshold conditions. In normal conditions, the amount of light available is sufficient. As a result, the new code developed by the British Illuminating Engineering Society no longer differentiates between the lighting requirements of old and young workers, while taking into account only the amount of light required to perform the task at the workplace. A relationship between the decrease in the sensitivity of the eye as a function of age and the presence of glare, has been established. Accordingly, the photic environment of the older workers can be improved by reducing the number of glare sources in their visual field. A correlation was also found between aging and the probability of developing ocular defects. The probability of acquiring some defect of the eye by age 70 was found to be 92 percent.
Lighting-systems; Age-factors; Illumination; Task-performance; Visual-perception; Eye-examinations; Eyesight
The Occupational Safety and Health Effects Associated with Reduced Levels of Illumination. Proceedings of a Symposium, July 11-12, 1974, Cincinnati, Ohio, NIOSH, Division of Laboratory and Criteria Development, HEW Publication No. (NIOSH) 75-142