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Objective: To examine the relationship between practice of visual ergonomics in the work from home setup and its effect on eye health during COVID-19 pandemic. And to propose mitigation strategies via easy to implement visual ergonomic practices.

For large-scale manned spacecraft bound for the Moon and Mars, lighting should be explored that can reduce safety risks while increasing visual capability. The use of appropriate lighting in large-scale manned spacecraft can provide astronauts with a comfortable and safe living and working environment while reducing the energy consumption of the lighting equipment. Visual acuity is an important aspect of the quality of the light environment. It directly determines the human eye’s ability to discern details and has an important impact on visual ergonomics and the efficiency of receiving visual in-formation. In this study, we investigated changes in the human eye’s visual acuity in a simulated spacecraft environment under three illuminances. 18 healthy persons participated in the study and tested binocular vision under three illuminance light environments. The results show that the amount of change in visual acuity decreased as the illuminance value increased, the rate of decrease gradually slowed down and eventually tended to be flat. We found that with 200 lx as the dividing line, increasing the illuminance value at low illuminance can significantly improve visual acuity.

A visual environment impaired by e.g. glare can cause eyestrain, visual symptoms and musculoskeletal strain. A Visual Ergonomics Risk Assessment Method (VERAM) consisting of both a subjective questionnaire and an objective risk assessment, have been used at 217 workplaces, mainly computer work. VERAM can be used to examine and prevent deficiencies and increase wellbeing as well as detecting risks in the visual work environment and suggest measures that can be used to reduce the risks. The questionnaire showed that eyestrain, visual symptoms and musculoskeletal strain are common among Swedish workers. The overall risk assessments for glare and amount of illuminance on work surface are divided into three categories, green – no risk, yellow – risk, and red – high risk. Risk of glare and insufficient illuminance was present at 66% and 49% of the assessed workplaces, respectively. When the risk of glare and illuminance levels was rated as red, the frequency of the subjective strain was higher.

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.

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.

Neck pain and headache are leading causes of years lived with disability globally, and the prevalence is gradually increasing from school age to early adulthood. These symptoms have been linked to the use of digital devices. However, there is little knowledge related to this topic in adolescents, who spend increasingly more time using digital media. The aim of the study was to investigate eyestrain, headache, and musculoskeletal symptoms in relation to the use of tablets and smartphones in healthy adolescents with normal vision. Fifty healthy adolescents aged 11 – 13 years (mean = 12.1 (SD = 0.53)) with normal vision and development participated. A vision examination was performed by an authorised optometrist and an interview questionnaire measuring eyestrain, headache, and musculoskeletal symptoms in relation to screen use was filled out. In addition, screen time, ergonomics, participation in sports, and outdoor time were obtained. Forty-nine (98%) of the 50 children used a smartphone and 17 (34%) used a tablet. Overall, 12% to 41% experienced symptoms of headache, neck pain, tiredness and/or tired eyes while using smartphones and tablets. Nine (18%) experienced at least one symptom often or always while using their device. Musculoskeletal pain and headache were significantly associated with vision and eyestrain. Tablet use was associated with increased symptom scores compared to smartphone use. Increased screen time and shorter viewing distance were associated with eyestrain, headache, and neck pain. Children with neck- shoulder- and back pain were significantly (2.1 hours) less physically active than children without these symptoms. Most adolescents with good health and vision had no symptoms while using smartphones and tablets. However, a significant proportion still experienced symptoms of headache, neck pain, tiredness and tired eyes, and these symptoms were associated. Symptoms increased with screen time, shorter viewing distance and reduced participation in sports. This suggests that even healthy children with good vision may develop vision symptoms and musculoskeletal pain. Awareness should be raised among parents, teachers, eye care- and health care personnel, of the importance of good visual ergonomics and physical activity to promote health in adolescents.

The present study aimed to identify whether or not an increase in ciliary-muscle contraction force, when the eye-lens is adjusted for viewing at a near distance, results in an increase in trapezius muscle activity, while performing a natural work task. Twelve participants, ranging in age from 21 to 32 years, performed a computer-mouse work task during free gaze conditions. A moving visual target was tracked with a computer mouse on a screen placed at two different distances from the eyes, 25 cm and 50 cm. Tracking performance, eye accommodation, and bilateral trapezius muscle activity were measured continuously. Ciliary-muscle contraction force was computed according to a formula which takes into account the age-dependent, non-linear relationship between the contraction force of the ciliary muscle and the produced level of eye accommodation. Generalized estimating equations analyses were performed. On the dominant hand side and for the nearest screen distance, there was a significant effect of ciliary-muscle contraction force on the trapezius muscle activity (p 0.05). The results support the hypothesis that high visual demands, during computer mouse work, increase ciliary muscle contraction force and contribute to a raise of the sustained level of trapezius muscle activity. The current study specifically clarifies the validity of the relationship between ciliary-muscle contraction force and trapezius muscle activity and demonstrates that this relationship is not due to a general personality trait. We conclude that a high level of ciliary muscle contraction force can contribute to a development of musculoskeletal complaints in the neck–shoulder area.

Visual ergonomics through ocular biomechanical analysis is an inviting, non-invasive method to add insights into the effect of immersion on our ocular system. It can also add insights into the mental and cognitive state, due to the tight coupling of eye movement and mental state. Eye movement tracking has been used in studying eye movement in normal activities and with the use of embedded eye trackers into virtual reality headsets, this can be easily extended into virtual environments. In this paper, we present a biomechanical analysis of eye movements recorded from subjects during immersion. Our objective is to validate the ocular biomechanical model used, through comparing recorded and muscle-driven eye movement. The regression analysis between the recorded eye movement and the muscle-driven eye movement shows a strong significant positive correlation. In addition, the computed extra-ocular muscle controls show agonist-antagonist relationships which is in accordance with the normal realistic eye movement. Insights into the different eye-head coordination styles performed by subjects are highlighted, too.

Digital Screens (DS) can be considered harmful to the eyes, if used for a prolonged time, leading to such health issues as computer vision syndrome (CVS) and digital eyestrain. A wearable device able to inform the user about the time spent looking at DS could be helpful in order to suggest him the proper break timings and avoid CVS. In this study, a new Digital Screen Detection (DSD) approach using a new generation of head mounted wearable color light sensor has been proposed. Data from five subjects during common activities of daily living (ADL) in different environments (indoor, outdoor, office, meeting room) characterized by the presence of various DSs (Tablet, PC, large screen) have been acquired. The best performing machine learning algorithms already applied in a previous in-lab controlled study have been analyzed. The results showed that, in ADL context, the Random Forest algorithm reached the best accuracy in DSD with the proposed system (79.3%).

In the past two decades, diagnostic radiology has changed in technology and frequency of imaging per patient. Further, the change from film to soft-based image diagnostics as well as further technological developments in cross-sectional and dynamic imaging have introduced new opportunities but also health hazards for radiologists, too.

Purpose: To extend our knowledge of the functional linkages between visual fatigue and regional cerebral prefrontal cortex (PFC) oxygenation, we measured time related hemodynamic changes over the right dorsolateral prefrontal cortex (dIPFC) during convergence load under conflicting stimulus-to-accommodation and stimulus-to-vergence eye movements with and without concurrent mental load. Methods: Twenty healthy participants with a median age of 28 years (range: 18-44 years) fixated upon a vertical bar presented separately to the left and right eyes, using polarized filters, during four counterbalanced 10-min periods: (i) no accommodation/vergence conflict (Control, Ctrl): (ii) added convergence load and accommodation/vergence conflict (Conv); (iii) added cognitive load only (Cog) and; (iv) a combination of added cognitive and convergence load and accommodation/vergence conflict (Cc). Viewing distance was 65 cm. Non-invasive measurements of hemodynamic activity over the dIPFC were quantified by functional near-infrared spectroscopy (fNIRS). During the two-convergence load conditions, the horizontal disparity of the two bars varied dynamically from no disparity to a disparity set 20% below the individual threshold for diplopia. Cognitive load was induced by the n-back-2 test which required the subject to memorize and recall the changing colors of the horizontal bars and decide when a given color was the same as that occurring two colors previously. fNIRS data were averaged over 10-s windows centered at 0, 2, 4, 6, 8, and 10 min of each task, subtracted from a 20-s baseline window immediately preceding the visual task, and then represented as changes in oxygenated hemoglobin (Delta HbO(2)), deoxygenated hemoglobin (Delta HHb) and total hemoglobin (Delta tHb). Results: Linear mixed model analyses showed that hemodynamic activity was systematically influenced by time (p < 0.001). The group-averaged time-related level of change across the viewing conditions did not differ when compared with one another (p > 0.05). Larger convergence eye-movement responses under conflicting stimulus-to-accommodation, and stimulus-to-vergence over time, increased Delta HbCO(2) and Delta tHb only in condition Cc and after 8 min of task time (p < 0.10 for min(-6) and min(-8): p < 0.05 for min(-10)). Discussion: Collectively, our data suggest that HbCO(2), HHb, and tHb, recorded over the dIPFC with fNIRS, can be used to assay the degree to which supervisory oculomotor control processes are activated during visually deficient near work., This study was in part supported by grants from the Swedish Council for Working Life, Social Research Grant 2009-1761 and from the Swedish Research Council, 2015-01116.

Aim To investigate if trapezius muscle activity increases over time during visually demanding near work. Methods The vision task consisted of sustained focusing on a contrast-varying black and white Gabor grating. Sixty-six participants with a median age of 38 (range 19–47) fixated the grating from a distance of 65 cm (1.5 D) during four counterbalanced 7-min periods: binocularly through −3.5 D lenses, and monocularly through −3.5 D, 0 D and +3.5 D. Accommodation, heart rate variability and trapezius muscle activity were recorded in parallel. Results General estimating equation analyses showed that trapezius muscle activity increased significantly over time in all four lens conditions. A concurrent effect of accommodation response on trapezius muscle activity was observed with the minus lenses irrespective of whether incongruence between accommodation and convergence was present or not. Conclusions Trapezius muscle activity increased significantly over time during the near work task. The increase in muscle activity over time may be caused by an increased need of mental effort and visual attention to maintain performance during the visual tasks to counteract mental fatigue.

Ergonomists and optometrists often have mutual clients/patients with complex visual needs in the workplace but communication between the professionals is usually indirect through the client/patient. This paper describes a joint professional development meeting between optometrists and ergonomists in Canberra, Australia, which included a discussion to explore how to improve communication between the two professions. Optometrists and ergonomists reported they would prefer more information before conducting assessments and providing advice. Vision screening forms commonly in use for computer workers were viewed as inadequate to meet these needs. Communication between the two professions was hampered by absence of contact details of the optometrist/ergonomist, perceptions that the other profession is too busy to talk, privacy considerations in sharing information and funding issues for shared care arrangements. There are opportunities for increasing awareness of good vision in workplaces. Communication between optometrists and ergonomists can be improved by developing information-sharing documents relevant to modern workplaces.

Despite the booming of the hair salon bringing a wide variety of hair design technology and tools; however, the innovative hand tools bring some problems, such as radio-ulnar clubhand due to the overuse of hands and wrong exertion, envolving occupational injury and the danger of use. The issue of occupational injury occurs with the development of every industry. At first, researches use Observational Method to understand the operational behavior and job requirements; using QFD to assess the design of the curing iron in the market is the most corresponding to the job requirements. The design of the curing iron for hair salon faces too many requirements in the market, so it produces special shapes for the hair style or for the convenience of using handles; however, these changes can’t improve the problem of customers burned and the operation of hands. In addition, The bad hand tool design can affect the force of the hands’ muscles, using for a long time will cause the tire of muscles and wrists, easily causing disease of muscles and bones, forming occupational injury further. The results of this study can reduce occupational injuries generation hair stylist hand. The results of this study can reduce the incidence of occupational injuries hairstylist hand, and provide design assessment.

Background Computer vision syndrome (CVS) is a collection of symptoms related to prolonged work at a computer display. Objective This article reviews the current knowledge about the symptoms, related factors and treatment modalities for CVS. Methods Relevant literature on CVS published during the past 65 years was analyzed. Results Symptoms reported by computer users are classified into internal ocular symptoms (strain and ache), external ocular symptoms (dryness, irritation, burning), visual symptoms (blur, double vision) and musculoskeletal symptoms (neck and shoulder pain). The major factors associated with CVS are either environmental (improper lighting, display position and viewing distance) and/or dependent on the user's visual abilities (uncorrected refractive error, oculomotor disorders and tear film abnormalities). Conclusion Although the factors associated with CVS have been identified the physiological mechanisms that underlie CVS are not completely understood. Additionally, advances in technology have led to the increased use of hand-held devices, which might impose somewhat different visual challenges compared to desktop displays. Further research is required to better understand the physiological mechanisms underlying CVS and symptoms associated with the use of hand-held and stereoscopic displays.

The type and level of lighting affects the assessment and outcome of important functional elements of vision. The type and level of lighting affects the low vision individual selectively. Depending upon their personal visual condition, lighting impacts their visual acuity, their visual ergonomics, their field of vision available to the task and the stability of that field. By assessing the individual's lighting needs, it is possible to combine improved visual aids with lighting strategies to address specific personal tasks such as reading bills and writing checks. Examples are given of results obtained at the National Association for the Visually Handicapped.

The static posture of postal workers when sorting mail can lead to musculoskeletal discomfort. Research has shown a connection between eyestrain and upper-body musculoskeletal discomfort in general, including postal workers. A previous study of postal workers found that most of those with eye strain were in need of a new correction in their existing spectacles.Evaluate intervention effects on eyestrain and musculoskeletal discomfort with new spectacles for postal workers.Postal workers subjectively reported eyestrain, musculoskeletal discomfort and their opinions of the visual environment via questionnaires pre- and post-intervention. After an eye examination the postal workers were divided into two groups: those who needed new spectacles and those who did not.Those who needed new spectacles showed a higher prevalence of eyestrain and musculoskeletal discomfort pre-intervention. Post-intervention, the postal workers rated their vision better and the average eyestrain and musculoskeletal discomfort decreased for both groups. These workers also experienced a decrease in discomfort on the left (static) side of the neck while sorting mail.An intervention providing the optimal correction reduces eyestrain and decreases musculoskeletal discomfort, especially from the neck.

This study was performed between 2004 and 2011 at mail sorting facilities in Sweden. During this time, different interventions were performed. The first was a lighting intervention that had a positive impact on the postal workers, especially those with eyestrain. A new lighting system also improved the illuminance and gave better light distribution. The second intervention involved new personal spectacles for the postal workers who needed them and this had a positive effect on eyestrain. The third intervention involved a specific type of sorting spectacles for the postal workers who already used progressive lenses privately. The reading distances that the postal workers had while sorting the mail was inverted to the distances in their regular progressive lenses. The new sorting spectacles had a positive effect on head postures and on muscular activity.

Visual requirements are high when sorting mail. The purpose of this visual ergonomics intervention study was to evaluate the visual environment in mail sorting facilities and to explore opportunities for improving the work situation by reducing visual strain, improving the visual work environment and reducing mail sorting time. Twenty-seven postmen/women participated in a pre-intervention study, which included questionnaires on their experiences of light, visual ergonomics, health, and musculoskeletal symptoms. Measurements of lighting conditions and productivity were also performed along with eye examinations of the postmen/women. The results from the pre-intervention study showed that the postmen/women who suffered from eyestrain had a higher prevalence of musculoskeletal disorders (MSD) and sorted slower, than those without eyestrain. Illuminance and illuminance uniformity improved as a result of the intervention. The two post-intervention follow-ups showed a higher prevalence of MSD among the postmen/women with eyestrain than among those without. The previous differences in sorting time for employees with and without eyestrain disappeared. After the intervention, the postmen/women felt better in general, experienced less work induced stress, and considered that the total general lighting had improved. The most pronounced decreases in eyestrain, MSD, and mail sorting time were seen among the younger participants of the group.

Three-dimensional computerized imaging with current advanced software (Cemax) has resulted in superior visual ergonomics and rapid data acquisition utilizing standard computed tomography (CT) or magnetic resonance imaging. Consequently, within 15-20 min of a standard CT scan, the information is available to be employed for operative planning, allowing this useful tool to be practical in emergency situations, such as trauma. The advanced lifelike imaging permits excellent preoperative planning due to correct demonstration of the surgical anatomy. We present three patients to illustrate the applications of this technology: one with a skull base tumor, another with a complex ethmoidal encephalocele, and a third with severe craniofacial trauma. We have found this technique to have a significant impact on the management of pediatric neurosurgery patients with complex pathology.

Ergonomic data was gathered for subjects reading in a "natural" position. Estimates of eye declination, reading distance and horizontal eye movement were found. Objective and subjective thresholds for blur were also investigated.

A large ocular surface area (OSA) is thought to be one of the causes of eye irritation and eye fatigue. Because ocular surface is very sensitive to various irritants such as dust, heat, dryness, air flow, etc., a large OSA increases the possibility of eye surface exposure to such irritants. Thus, OSA is one of the most important indices of visual ergonomics. This paper aims at making OSA an exact and practical index by first describing an accurate method of measuring it, and then clarifying the relationship between OSA, the width of the palpebral fissure, and vertical gaze direction, all of which are thought to be strongly correlated with each other. We derived the following equations: 1) y = 0.039x1 + 3.36, r = 0.99, 2) y = 3.05x2 - 0.39, r = 0.97, 3) x1 = 72.7x2 - 91.4, r = 0.97, where x1 = vertical gaze direction (degrees), x2 = width or the palpebral fissure (cm), y = OSA (cm2). Finally, this paper also introduces the practical applications of OSA measurement, and notes the differences between OSA when VDT work (word processing using a keyboard and drawing a picture using a mouse) is performed and when traditional office work without a VDT (reading, drawing, and writing) is performed.

IntroductionThe Visual Ergonomics Risk Assessment Method (VERAM) is a newly developed and validated method to assess visual ergonomics at workplaces. VERAM consists of a questionnaire and an object ...