The Subjective and Objective Assessment of Color Selection and Light Intake with Regard to Employee Performance

Abstract

Employees’ physical and mental health is significantly influenced by the light intensity and color environment of their workstations. The goal of this research was to determine the influence of workspace color variations and lighting intensity on employees’ physical and mental comfort. Objective assessment by measuring physical condition including heart rate and blood pressure using the design of experiment methods (DOE). The subjective rating using the National Aeronautics and Space Administration Task Load Index (NASA-TLX) method is to perform a working mental burden measurement consisting of six-dimensional indicators including Mental Demand, Physical Demand, Temporal Demand (TD), Own Performance, Frustration Level, Effort. Measurements were recorded before and after the color and intensity of the light in a three-meter long, three-meter wide, and three-meter high chamber by adjusting the color of the walls to red, blue, or white and noting changes in the physical environment and the respondent's mental stress level. Objective measurement tests for DOE included measuring degrees of physical comfort using blue and lighting from 300 lux to 350 lux. The highest ranking was systole of 100.9 mmHg, down 5.48%; diastole, down 2.71%; and heart rate, down 2%. The same thing occurred in measuring the level of mental comfort with NASA TLX: the blue color and light intensity of 300 lux to 350 lux produced the lowest stress value of 55.67, down 18.40%. Results showed the effect of the blue color and the lighting can lower the blood pressure, heart rate, and mental burdens of employees, thus improving employees’ comfort.