Author: Monazzam MR1, Shoja E2, Zakerian SA1, Foroushani AR3, Shoja M4, Gharaee M4, Asgari A5
1Occupational Hygiene Department, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
2Department of Occupational Hygiene Engineering, Esfarayen Faculty of Medical Sciences, Esfarayen, Iran. firstname.lastname@example.org.
3Epidemiology and Biostatistics Department, Tehran University of Medical Sciences, Tehran, Iran.
4Department of Epidemiology, Esfarayen Faculty of Medical Sciences, Esfarayen, Iran.
5Department of Environmental Health Engineering, School of Public Health, Ardabil University of Medical Sciences, Ardabil, Iran.
Conference/Journal: Int Arch Occup Environ Health.
Date published: 2018 Mar 12
Other: Special Notes: doi: 10.1007/s00420-018-1301-z. [Epub ahead of print] , Word Count: 260
PURPOSE: This study aimed to investigate the effect of whole-body vibration and ambient lighting, as well as their combined effect on human discomfort, heart rate, and reaction time in laboratory conditions.
METHODS: 44 men were recruited with an average age of 25.4 ± 1.9 years. Each participant was subjected to 12 experimental steps, each step lasting five minutes for four different vibration accelerations in X, Y, and Z axes at a fixed frequency; three different lighting intensities of 50, 500, and 1000 lx were also considered. At each step, a visual computerized reaction test was taken from subjects and their heart rate recorded by pulse oximeter. In addition, the discomfort rate of subjects was measured using Borg scale.
RESULTS: Increasing vibration acceleration significantly increased the discomfort rate and heart beat but not the reaction time. Lack of lighting caused more discomfort in the subjects, but there was no significant correlation between lighting intensity with heart rate and reaction time. The results also showed that the combined effect of vibration and lighting had no significant effect on any of the discomfort, heart rate, and reaction time variables.
CONCLUSIONS: Whole-body vibration is an important factor in the development of human subjective and physiological reactions compared to lighting. Therefore, consideration of the level of vibration to which an individual is exposed in workplaces subject to vibration plays an important role in reducing the level of human discomfort, but its interaction with ambient lighting does not have a significant effect on human subjective and physiological responses.
KEYWORDS: Discomfort; Heart rate; Lighting intensity; Reaction time; Whole-body vibration
PMID: 29532145 DOI: 10.1007/s00420-018-1301-z