Evaluation of sleep quality and sleepiness characteristics of the staff and its relationship with the light source parameters used in the work room

Document Type : Original Article

Authors

1 Department of Color Imaging and Color Image Processing, Institute for Color Science and Technology, Tehran, Iran

2 Textile Engineering Department, Kar Higher Education Institute, Qazvin, Iran

3 Center of Excellence for Occupational Health and Research Center for Health Sciences, School of Public Health, Hamadan University of Medical Sciences, Hamadan, Iran

Abstract

Performance, level of consciousness and concentration of staffs at work could be affected by a series of color physics parameters among which parameters related to lighting of work environment could be noticed. Physical factors in working environment has direct effect on the visual, psychological and health needs of individuals so to improve the quality of all the places, especially indoor spaces, lighting as a physical factor in working environments should be considered. If the quality and quantity of lighting of working room cannot be provided properly, it can be a risk factor for the emergence of some complications such as visual, physical and mental disorders. In this study, the relationship between the psychological characteristics of the staff in their working room and the physical parameters associated with the used light sources, i.e. illuminance and correlated color temperature (CCT) were considered. The questionnaire of the Pittsburgh sleep quality and the Karolinska sleepiness scale as well as the selective & divided attention test were used for the psychological analysis. The parameters of illumination were measured in time intervals as at the first, mid, and end of the work shift for 21 rooms with the artificial light sources. The results showed that the low consciousness level can be improved to some extent by the factors such as correcting lighting conditions and light sources in terms of intensity of lighting and correlated color temperature.

Keywords


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