Lighting at computer workstations

Physical work environment in an activity-based flex office: a longitudinal case study

OBJECTIVE

This study aimed to investigate and explore Occupational Health and Safety (OHS) management, office ergonomics, and musculoskeletal symptoms in a group of office workers relocating from cell offices to activity-based flex offices (AFOs).

METHODS

The analysis was based on qualitative interview data with 77 employees and longitudinal questionnaire data from 152 employees.

RESULTS

Results indicate that there was a need to clarify roles and processes related to the management of OHS. Self-rated sit comfort, working posture, and availability of daylight deteriorated and symptoms in neck and shoulders increased after the relocation and seemed to be influenced by many factors, such as difficulties adjusting the workstations, the availability of suitable workplaces, and age, sex, and individual needs.

CONCLUSION

Research on the long-term effects of physical work environments and management of (OHS) issues after implementing activity-based flex offices is sparse. This study demonstrates the importance of planning and organising OHS issue management when implementing an AFO, and to carefully implement office ergonomics among office workers.

Algorithmic and sensor-based research on Chinese children's and adolescents' screen use behavior and light environment

Background

Myopia poses a global health concern and is influenced by both genetic and environmental factors. The incidence of myopia tends to increase during infectious outbreaks, such as the COVID-19 pandemic. This study examined the screen-time behaviors among Chinese children and adolescents and investigated the efficacy of artificial intelligence (AI)-based alerts in modifying screen-time practices.

Methods

A cross-sectional analysis was performed using data from 6,716 children and adolescents with AI-enhanced tablets that monitored and recorded their behavior and environmental light during screen time.

Results

The median daily screen time of all participants was 58.82 min. Among all age groups, elementary-school students had the longest median daily screen time, which was 87.25 min and exceeded 4 h per week. Children younger than 2 years engaged with tablets for a median of 41.84 min per day. Learning accounted for 54.88% of participants' screen time, and 51.03% (3,390/6,643) of the participants used tablets for 1 h at an average distance <50 cm. The distance and posture alarms were triggered 807,355 and 509,199 times, respectively. In the study, 70.65% of the participants used the tablet under an illuminance of <300 lux during the day and 61.11% under an illuminance of <100 lux at night. The ambient light of 85.19% of the participants exceeded 4,000 K color temperature during night. Most incorrect viewing habits (65.49% in viewing distance; 86.48% in viewing posture) were rectified swiftly following AI notifications (all p < 0.05).

Conclusion

Young children are increasingly using digital screens, with school-age children and adolescents showing longer screen time than preschoolers. The study highlighted inadequate lighting conditions during screen use. AI alerts proved effective in prompting users to correct their screen-related behavior promptly.

Effect of illuminance and colour temperature of LED lighting on asthenopia during reading

PURPOSE

A self-controlled study to determine the influence of illuminance and correlated colour temperature (CCT) of light-emitting diode (LED) lighting on asthenopia.

METHODS

Twenty-two healthy postgraduates (nine women) were recruited to read under eight LED lighting conditions with four illuminances (300 lx, 500 lx, 750 lx and 1000 lx) and four CCTs (2700, 4000, 5000 and 6500 K) for 2 h. A subjective asthenopia questionnaire, the optical quality analysis system (OQAS) and an inflammatory cytokine assay were used to assess the levels of asthenopia.

RESULTS

Increased asthenopia was observed after reading, but the degree varied with lighting conditions. There were significant differences among the groups in terms of subjective symptoms (inattention, eye pain, dry eye and total score), optical performance parameters (modulation transfer function [MTF] cut-off frequency, Strehl ratio [SR], objective scattering index [OSI], mean OSI and accommodative amplitude [AA]) as well as inflammatory cytokines in the tears (epidermal growth factor [EGF], transforming growth factor [TGF]-α, interleukin [IL]-6, IL-8, macrophage inflammatory protein [MIP]-1β, tumour necrosis factor [TNF]-α, TNF-β and vascular endothelial growth factor [VEGF]-A). All of the subjective and objective measurements collectively suggested that asthenopia was lessened for the 500 lx-4000 K condition. However, asthenopia was significantly worse for 300 lx-2700 K and 1000 lx-6500 K in terms of subjective symptoms and objective optical performance, respectively.

CONCLUSIONS

LED illuminance and CCT do have a significant effect on asthenopia during reading. 500 lx-4000 K lighting resulted in the lowest level of asthenopia. Conversely, low illuminance at low CCT (300 lx-2700 K) and high illuminance at high CCT (1000 lx-6500 K) promoted more severe asthenopia.

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 the 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 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.

The Physical Learning Environment of Online Distance Learners in Higher Education - A Conceptual Model

Online distance learning is offered not only in post-secondary distance education institutions but in traditional universities as well. With advances in mobile and wireless technologies, completing academic studies anywhere anytime should become feasible. Research in distance education and online learning has focused on computer-mediated communication, instructional design, learner characteristics, educational technology, and learning outcomes. However, little attention has been given to where exactly learners do their learning and studying and how the physical and social aspects of the physical environment within which the online learner is physically embedded (e.g., the home) supports and constrains learning activities. In this paper, the author proposes a conceptual model for understanding the role that the physical environment plays in online distance learning in higher education, drawing on theories and research in environmental psychology, online learning, telework and mobile work, and higher education. Several gaps in research are identified, and suggestions for future research are proposed.

The Physical Learning Environment of Online Distance Learners in Higher Education - A Conceptual Model

Online distance learning is offered not only in post-secondary distance education institutions but in traditional universities as well. With advances in mobile and wireless technologies, completing academic studies anywhere anytime should become feasible. Research in distance education and online learning has focused on computer-mediated communication, instructional design, learner characteristics, educational technology, and learning outcomes. However, little attention has been given to where exactly learners do their learning and studying and how the physical and social aspects of the physical environment within which the online learner is physically embedded (e.g., the home) supports and constrains learning activities. In this paper, the author proposes a conceptual model for understanding the role that the physical environment plays in online distance learning in higher education, drawing on theories and research in environmental psychology, online learning, telework and mobile work, and higher education. Several gaps in research are identified, and suggestions for future research are proposed.

Neck and upper extremity pain in sonographers - a longitudinal study

Background

Sonographers have reported a high occurrence of musculoskeletal pain for more than 25 years. Assessments of occupational risk factors have previously been based on cross-sectional surveys. The aim of this longitudinal study was to determine which factors at baseline that were associated with neck/shoulder and elbow/hand pain at follow-up.

Methods

A questionnaire was answered by 248 female sonographers at baseline and follow-up (85% of the original cohort). 208 were included in the analyses. Physical, visual, and psychosocial work-related conditions were assessed at baseline. Pain in two body regions (neck/shoulders and elbows/hands) was assessed at both baseline and follow up.

Results

Pain at baseline showed the strongest association with pain at follow-up in both body regions [prevalence ratio (PR) 2.04; 95% confidence interval (CI) 1.50–2.76], for neck/shoulders and (PR 3.45; CI 2.29–5.22) for elbows/hands. Neck/shoulder pain at follow-up was associated with inability of ergonomic adjustments at the ultrasound device (PR 1.25; CI 1.05–1.49), a high mechanical exposure index (PR 1.66; CI 1.09–2.52), and adverse visual conditions (PR 1.24; CI 1.00–1.54) at baseline. Moreover, among participants with no neck/shoulder pain at baseline, high job demands (PR 1.78; CI 1.01–3.12), and a high mechanical exposure index (PR 2.0; CI 0.98–4.14) predicted pain at follow-up. Pain in the elbows/hands at follow-up was associated with high sensory demands at baseline (PR 1.63; CI 1.08–2.45), and among participants without pain at baseline high sensory demands predicted elbow/hand pain at follow-up (PR 3.34; CI 1.53–7.31).

Conclusion

Pain at baseline was the strongest predictor for pain at follow-up in both body regions. We also found several occupational factors at baseline that were associated with pain at follow-up: inability to adjust equipment, adverse visual conditions, a high MEI, high job demands and high sensory demands. These results point at a possibility to influence pain with better ergonomics.

Visual fatigue during control room work in process industries

BACKGROUND

Working in front of computer screens is visually demanding and related to adverse eye symptoms. Occurrence of glare further increases visual fatigue.

OBJECTIVE

This paper presents results from an examination of visual ergonomics in control room environments at two Swedish process industries.

METHODS

Visual conditions were examined and evaluated in nine control rooms and eighteen process operators answered questions about their perceived workload and visual experiences.

RESULTS

When working in the control rooms, the mental workload was rated significantly higher by the participants, compared to experienced performance. The operators further experienced significantly higher visual fatigue and blurred vision compared to double vision and sore eyes. Visual demands were increased in conditions where contrast glare was present, as well as frequent changes of focusing distances, and low contrast between background and characters in computer screens.

CONCLUSIONS

Suboptimal visual working conditions in the control rooms contributes to increased visual demands on the operators. Presence of glare is leading to visual fatigue and an unnecessary high mental load. The findings support the relevance of considering principles of general and visual ergonomics when designing and organizing work in control rooms. Workstation design should also be flexible to allow for individual and contextual adjustments.

The pitfalls of the traditional office ergonomics model in the current mobile work environment: Is visual ergonomics health literacy the remedy?

Mobile technology has revolutionised how we work. It is now relatively easy to work anywhere and anytime, but this has placed the onus is on mobile (or flexible) workers to set up their own work environment for comfort and ease of use. Vision is an important driver of posture, and hence visual ergonomics principles are integral for setting up digital devices. If mobile workers do not have visual ergonomics knowledge, or are unable to apply visual ergonomics knowledge to appropriately set up their work environment, then they are at risk of developing visual-related occupational health issues due to exposure to adverse physical work environments. To address this potential health care issue, we propose the introduction of Visual Ergonomics Health Literacy. This would provide mobile workers (including school children) with the knowledge and skills to set up their work environment for comfort and ease of use, wherever they work. It is important to address this issue now before we have a widespread epidemic of discomfort and injury from not applying sound visual ergonomics principles to work environments.

The Effects of Lighting Problems on Eye Symptoms among Cleanroom Microscope Workers

The visual health of microscope workers is an important occupational health concern, and a previous study suggested an association between lighting problems (e.g., flashing light, insufficient lighting) and eye symptoms among cleanroom workers in the electronics industry. This study aimed to explore the association between eye symptoms and lighting problems, as well as light-related counteracting behaviors among microscope workers in the cleanroom environment. Ninety-one cleanroom workers aged 20 years or older were recruited from an electronics factory. The socio-demographic factors, work-related factors, eye symptoms, and lighting problems were assessed using a self-administered questionnaire. There were 92.3% female participants in this study. Among all participants, 41.8% and 63.7% had symptoms of dry eye and eye fatigue, respectively. The counteracting behaviors of needing to move closer (adjusted odds ratio (aOR) = 3.47, 95% CI = 1.11 to 10.88) was significantly associated with dry eye symptoms. Workers who were more experienced at the job (aOR = 1.03, 95% CI = 1.01 to 1.06) and had shorter break times (aOR = 0.94, 95% CI = 0.91 to 0.98) were more likely to have eye fatigue. As a result of these findings, this study suggests that good lighting and adequate break times are crucial to improve the visual health of cleanroom microscope workers.