Visual ergonomics, performance and the mediating role of eye discomfort: a structural equation modelling approach.

The purpose of this study was to model the visual ergonomic factors affecting performance in human-computer interaction. A cross-sectional study using structural equation modelling was performed with a sample of 200 participants. The measuring instruments included the office lighting survey questionnaire, performance assessment questionnaires, visual ergonomics assessment and an eye discomfort assessment. The hypothetical model evaluated workplace lighting status and visual ergonomics as precursors, performance as the output and eye discomfort as a mediator. The results showed that eye discomfort directly affected performance. Visual ergonomics also had a significant direct effect on eye discomfort. The final model suggested a significant new path between the quality of lighting and visual ergonomics. Also, the quality of lighting had an indirect effect on eye discomfort and performance, and the effect of visual ergonomics on performance was the same. Improving the lighting quality and visual ergonomics can reduce eye discomfort and increase performance.

Investigating the short-term effects of using full-body hospital personal protective equipment and changes in physical workload intensity on human physiological and cognitive performance.

The present study investigated the short-term effects of using Personal Protective Equipment (PPE) and physical workload intensity on human physiological and cognitive performance among 21 males and 19 females. PPE1 consisted of a medical coverall and surgical mask, while PPE2 consisted of impermeable full-body coverall, shoe covers, latex gloves, N95 mask, and face shield. Objective assessments were heart rate, energy expenditure, core body temperature, clothing microclimate temperature and humidity, and cognitive performance were the continuous performance test and N-Back test. Subjective assessments included thermal sensation, perceived fatigue/skin wetness/clothing moisture. Using PPE2 and increased workload intensity significantly increased the values of all physiological parameters and the subjective ratings of fatigue, thermal sensation, skin wetness, and clothing moisture. Moreover, the participants' cognitive performance was not affected by the type of PPE.Practitioner summary: Healthcare workers are at the highest risk in the fight against pandemics. Therefore, these people are required to use personal protective equipment. Using this equipment may have difficulties. The results show physiological strain and higher subjective ratings associated with using full-body hospital PPE and increased physical workload.

Subjective and objective survey of office lighting: effects on alertness, comfort, satisfaction, and safety.

BACKGROUND: Lighting is one of the workplace factors that can relevantly impact workers' health, performance, safety, and job satisfaction. Brightness, natural light and color temperature are the factors that affect the quality of lighting. This study involved subjective and objective evaluation of office lighting and its effects on workers' alertness, comfort, satisfaction, safety, and performance in a prominent government office. METHODS: Visual comfort, alertness, performance, safety and satisfaction were assessed subjectively using the questionnaires and rating scales. Moreover, illuminance, color temperature of light sources, and natural light availability were evaluated objectively. RESULTS:  The findings of this study indicated that the use of natural light in the workplace could increase the illuminance and color temperature of light in the workplace and improve alertness, visual comfort, satisfaction and worker's preference. Conclusions: To improve the quality of lighting in the workplace, factors affecting it, such as the color temperature and the availability of natural light, should be considered.