Improving our understanding of muscle response towards assistive force is important not only to ensure the effectiveness of assistive devices but also to avoid injury due to excessive assistance. Therefore, the objective of this study was to compare muscle activities towards assistive force during isometric elbow flexion in young and elderly participants. The study involved right-handed young (n = 9, 25.3 ± 2.4 years) and elderly (n = 9, 68.4 ± 3.3 years) male participants and determined the maximum voluntary contraction (MVC) and maximum workload for each participant. The participants performed isometric elbow flexion under two conditions of submaximal workload (20% and 40%) and three levels of assistive force (0%, 50%, and 100%). The electromyographic activity of agonist and antagonist muscles decreased with increased levels of assistive force under both workload conditions in both groups. In addition, a more effective reduction in electromyographic activity was observed during 50% assistance in both muscles for both groups. In summary, assistive force relieved the exertion in the agonist muscle in both young and elderly groups; however, their effects were influenced by the level of assistive force.
Study was conducted with an aim to i) study the lower limb biomechanics of healthy workers, ii) determine changes of human biomechanics with different modes of load carriage and iii) suggest biomechanically efficient mode of load carriage. Study was conducted on 20 workers in the age range 20 to 55 years. Qualisys Motion Capture System (Sweden), Kistler Force Plate (Switzerland) and Polar S810i HR monitor, Finland were used. Heart rate was recorded at rest and during different modes of load carriage with 40% of body weight i.e. loads on head, shoulder and hand. Movement of lumbar spine while carrying loads was recorded by using Industrial Lumbar Motion Monitor (iLMM), USA. Walking speed for head load, shoulder load and hand load were 4.19±0.55 km.hr-1, 4.09± 0.82 km.hr-1 and 3.94± 0.84 km.hr-1respectively. Stride length was longer in case of head mode (1.20±0.45 meter) followed by hand (1.19±0.01 meter) and shoulder mode (1.12±0.04 meter) of load carriage. Average Twisting Velocity of lumbar spine was found lowest in case of head mode of load carriage followed by shoulder and hand mode. Heart Rate cost of carrying loads on head, shoulder and hand were 50±10.54 beats/min, 52.95±10.88 beats/min and 57.45±10.04 beats/min respectively. Energy cost of cost of carrying loads on head, shoulder and hand were 294±61.99 jule/min, 311.346±63.97 jule/min and 337.81±59.03 jule/min respectively. Results demonstrated a significant relationship between kinetic and kinematic parameters of workers at different load conditions. Findings would provide substantial input for designing work and work rest cycle for industrial workforce.
Human head needs to be protected from any risk as multiple sensory organs are located there. Hence it is very important to design products with a high level of comfort and fit in order for the product to perform its function. With the advancement of 3D scanning facilities, it is possible to acquire highly accurate and precise surface contour which can be used for designing customized products. With the availability of wide range of 3D scanners, it is necessary to evaluate the user experience of products developed from different scanners based on their accuracy and precision in scanning. The aim of this study is to investigate the effect of accuracy of three 3D scanners in product designing and evaluating user’s comfort and fit parameters for the developed products. Participants were scanned using three different 3D scanners (Artec Eva 3D scanner, Cyberware 3030 color scanner and Structure sensor scanner). A mask frame was developed from every scan and then 3D printed for evaluation. The individuals were made to evaluate the designed mask frame to understand their comfort and fit experience. Based on the responses from the participants it was found that the mask frame developed from the scan acquired from Artec Eva 3D scanner was found to be the most comfortable one and had the best fit. The scans acquired from Cyberware 3030 color scanner had missing data and was reported slightly dissatisfaction on fit. The scans from the Structure sensor lacked precision and fine details, and the frame got the lowest rating at comfort level.
A workplace with good consideration of ergonomics in the design which can prevent musculoskeletal discomfort, improve productivity and work efficiency, reduce production costs and optimize human well-being. This paper aims to summarize the research findings of six aspects of applying ergonomics principles in workplace design. This paper will answer the following questions: (1) Why should use ergonomics principles in workplace design? (2) Who should consult and consider in workplace design? (3) When should use ergonomics principles in workplace design? (4) Where should apply ergonomics in workplace design? (5) How to use ergonomics in workplace design? (6) What are the ergonomics principles in workplace design? The workplace design should consider full spectrum of users group with different physical and psychological needs. Ergonomics should be well considered in the design stage and the pre-occupant and post-occupant inspections should be used to evaluate the actual environment. The design should consider both the work and non-work area in the workplace that including the design of workstation, staff facilities, tools and work environment. Staff consultation should be organized in the design stage for collecting the opinion of the staff. A good workplace design can enhance employees' satisfaction and well-being. The environmental comfort model by Visher (2008) illustrated that there are three levels of comfort, (1) physical comfort; (2) functional comfort; and (3) psychological comfort. In addition, a good quality of environmental quality will create a higher quality of employees' work life and ultimately will have positive effect to the employee well-being and quality of life. In conclusion, ergonomic workplace design can facilitate occupational safety and health, work efficiency and employee well-being.
Pressure and distortion imposed by automatic care beds can lead to negative effects during interaction process. Motion discrepancy between human body and care bed surface causes shear as another type of risks. While relationship between structure design and risk remains unclear. To quantify design limitation and predict the feasibility of Automatic Care Bed(ACB) in lateral turning over Tasks, a virtual man-bed system was established according to two types of structures. A mannequin was modified to simulate patients of different types of figure. Eighteen subjects (6 males and 12 females) were measured by a pressure mapping system for interaction data collection. Distortion, pressure and friction caused by motion discrepancies were quantified to assessed the negative effect of existing structures of care beds. Possibility of structure redesigned is recommended to reduce pressure and distortion. Some auxiliary structures are used to relieve shear and friction.
This paper presents the methodologies and the systematic approaches of human factor ergonomics considerations in designing a Glucose Sensor device. The Glucose Sensor device is a non-invasive version of glucose sensor utilizing NIR (Near Infra-Red Spectroscopy) for medical application that provides diabetes screening as an early symptom in diagnostic. Contextual inquiry (CI) was conducted at the early stage to gather all the users' inputs and feedback and KJ Analysis was applied to prioritize the voice of customer. Hence, the customer needs could be identified as our design requirements. This study encompasses the ease of use and the usability of the Glucose Sensor device on the two main product features which are thumb module design and LCD placement. Prototypes had been developed to assess the design effectiveness and the discussion will be carried out at the end of this paper.
The compression forces on disc of spine were recommended from The National Institute for Occupational Safety and Health (NIOSH). The safety level for disc compression forces during lifting object in manual material handling should less than 3,400 N. There are many studies about disc compression forces in manual material handling, but manual human handling less researched. The aim of this study is to compare L4/L5 compression forces in four manual human lifting techniques and three phases of lifting and transferring. Thirty two subjects lifted a 60±5 kilogram person in four techniques: two-handed seat carry, four-handed seat carry, Fore-and-Aft carry and Chair carry from table height 50 cm walked 9 m, rested 3-5 minutes between each technique. Lifting and transferring was divided 3 phases (origin lift, carry and destination lift). Five cameras were installed in different angle of views to record subject movement during lifting. The static mode of the University of Michigan's Three-Dimensional Static Strength Prediction Model (3DSSPP) was used to predict lumbar disc compression forces (L4/L5) in each technique during lifting. Only origin lift phase has the average maximum L4/L5 compression forces more than 3,400 N especially Two-handed seat carry and Four-handed seat carry techniques. The results of L4/L5 compression forces of manual human lifting might help to prevent lifters or authorities from back injury.
Walking is essential to our everyday lives, both socially and in our ability to perform basic everyday tasks. However, a significant number of people suffer from walking difficulties, especially people of older ages. Smart walkers are assistive devices that support independent living by extending the capabilities of four-wheeled walkers. The augmentative nature of this device means that there is a need for compatibility with the user's gait and balancing needs. This aspect has not yet been fully explored as most previous studies have focused upon the technological features of smart walkers. This paper aims to highlight and elaborate upon some of the challenges associated with developing smart walkers from an ergonomics perspective.
Background: Ergonomic hazards are the most important causes of knee osteoarthritis (OA) in aged para rubber farmers. Ergonomic management comprising working condition improvement and muscle strengthening exercise has been well-documented in terms of workers’ health benefit. However, those interventions were not adequate to sustain the advantage. Few studies have demonstrated the effect of integrating participatory ergonomic management (PEM) in Non-Weight-Bearing Exercise (NWE) and Progressive Resistance Exercise (PRE) and none has focused on aged para rubber farmers with knee osteoarthritis. This study investigated the effect of PEM-NWE, PEM-PRE and standard treatment (STG) on self-care and functional ability in the aged population.
Methods: A single-blinded, clustered randomized controlled trial was carried out. Participants (n =75) from 3 different communities in southern Thailand were randomly assigned to PEM -NWE, PEM-PRE, and STG. Self-care and functional ability (pain, stiffness, and physical function) were examined at baseline (B), during the intervention at week 5 (W5) and after its completion at week 9 (W9). Mean comparison of those outcomes overtime was made using Generalized Linear Mixed Models (GLMM).
Results: Compared to the standard treatment, the means both groups PEM-NWE and PEM-PRE were significantly increased in self-care. However, no significant difference between PEM-NWE and PEM-PRE was found.
Conclusions: Either or both interventions should be incorporated into nursing practice in order to promote occupational health and enhance quality of work life for the Thai aged farmers. The further study on their cost-effectiveness is highly recommended.
This research study aims to identify the present and probable problems of the current ultrasound workstation being used at De La Salle University - Medical Center and provide improvements and recommendation to their current workstation to increase comfort and decrease pain. The current workstation was assessed and evaluated using different ergonomic tools. Data gathered were compared with the ergonomic standards to determine if the current workstation is fit for the radiologic technologists and safe from risks and injuries. The study focused on solving the problem regarding their posture while performing the ultrasound procedure. The RULA scores were 5.43 and 4.86 for the right hand (abdomen and thyroid) and 3.43 for the left hand, which indicates that further investigation and change on the current workstation is needed soon. The Postural Analysis showed that they stretch their wrist 65% of the time, their right elbow not assisted 80% of the time, and they raise their shoulder 81% of the time. While the Nordic questionnaire, focus group discussion, and comfort survey indicated that the participants experienced pain in their body parts specifically their right wrist, right shoulder, arm, and back.
Voice interaction between users and IT devices has become possible through voice user interface. Since VUI is based on vocabulary language, the most basic form of human communication, it lowers the entry barrier for those who experience difficulty using graphic user interface (GUI) or situations where using IoT devices with tiny screen or no screen at all. User experience can be a critical marker for the development of technology, however, few academic researchers have attempted to investigate the users' speech behavior pattern when they use VUI. Therefore, this study aims to provide insight about guidelines and design feedback for the novice users through observation in their adaption process of VUI. The author investigated speech patterns of error correction through observing ‘iPhone Siri' users who have less experience on VUI. Through the 7 days Siri usage history, the speech behavior patterns of error correction were analyzed in tone (amplitude, pitch, and duration), and in sentences (sentence elements or structure) based on the Communication Accommodation Theory. The results of this study can be summarized as follow; 1) After the first error, users change their speech tone and sentences at a similar rate, 2) but, when the second error occurred, they change sentences more, 3) the speech behavior patterns after error were different depending on the types of errors and 4) the users' speech behavior patterns were changed depending on time period of use. This study has primarily focused on variation in use behavior by observing real user experience. Through demonstrating how users respond to the situations of errors, this research has practical implications for the industry as it can positively contribute to the development of VUI voice feedback design and improve user experience on VUI.
The aim of this study is to establish pedestrian experience(PX) principles of the mobility handicapped. Due to the increasing attention to the pedestrian-friendly walking environment, walkability has been studied in the various field. However, walkability has been studied mainly in terms of ease and safety of walking although the walking environment has various functional aspects to a pedestrian as well as walking. It is difficult to reflect various experiences of the pedestrian as a concept of walkability. PX is a concept that expands the walkability to mirror diverse experiences of pedestrians. PX research needs to be given priority for those who often face with discomfort during walking. To constitute PX principles, we investigated which goals the existing studies set to design a pedestrian-friendly walking environment. The PX principles were supplemented by two methods; in-depth interview with the workers who works for the mobility handicapped and diary method with the mobility handicapped. The participants of in-depth interview worked for six types of the mobility handicapped; the visually impaired, hearing impaired, mentally handicapped, physically challenged, the aged, and a child. The types of those who participated in the diary method were the hearing impaired, mentally handicapped, physically challenged. Four PX principles and eight-teen sub-principles were derived. PX principles we suggested would help to design walking environment for the pedestrian.
This study evaluated flexible display concepts (foldable, rollable, and bendable) using the strategy canvas, and determined screen sizes suitable for each of five major smartphone tasks on foldable display concepts and preferred folding methods. Before using the strategy canvas to compare design concepts, two focus group interviews were conducted. The first interview was done with four design major students and the second with four human factors engineering major students. A total of 44 evaluation criteria obtained from these interviews were comprised of advantages, disadvantages, and characteristics of each flexible display concept. Thirty three evaluation items were selected and used when five researchers independently evaluated each flexible display concepts. The means of five evaluations were used to draw the strategy canvas. The foldable display concepts were scored the highest while the rollable display concept was scored the lowest. For the preferred screen sizes and the folding methods, a small screen size was preferred for the calling task, while a medium screen size was for the search and game tasks. An outward-folded screen type was preferred over an inward-folded type for one-fold screen concepts, while a z type (outward- and inward- folded screen) was preferred among three two-fold screen concepts. Overall, the z type was the most preferred concept. These findings will help to design ergonomic foldable display products and to improve rollable design concepts.
The Philippines is considered as the BPO capital of Asia due to Filipinos ability to speak English as a second language. Because of this, BPO has become an industry that contributed to the economic growth for decades.
Since the industry that employs workers at various times of the day, particularly at nighttime, various talent management programs have been in place to attract a skilled workforce. However, in the light of attractive compensation and generous benefits – companies overlooked the important aspect of ergonomics issues in call center management such as workstation design, shiftwork and its effects and computer-related disorders. It was observed that call center work in the Philippines lacked focus on considering these factors, making talent management more diagnostic than preventive in avoiding employee burnout, thus making skilled talent move from one call center to another, or worse to another industry and making a career change for good.
This paper will provide a conceptual framework of linking ergonomics and sustaining talent in the Business Process Industry, a look at the Philippine setting. By addressing so, it will also measure the employees' productivity which resulted in the competitiveness, growth and profitability of these call centers. This paper aims to investigate the transformative nature these BPO has employed ensure they get to keep the best talent not because of the attractive compensation and benefits they offer but the level of seriousness management has placed to alleviate workplace conditions to address these ergonomic issues of shiftwork, workstation design and computer-related disorders.
Working on a computer for four to six hours a day can lead to high incidences of work-related musculoskeletal disorders (WMSDs). Several factors of WMSDs including personal, work characteristics, work environment and stress. Several tools have been used to investigate incidences and factors affecting WMSDs. Most tools need experienced investigators to perform data collection and they have not covered risk factors. There is an Online Self-report Questionnaire on Computer Work related Exposure (OSCWE), which can assess risk factors of WMSDs. But, its internal consistency was low in some items. This study aimed to revise the OSCWE and investigate its content validity in order to use it in more general target groups. A new version of OSCWE was developed by 3 physical therapy lecturers involving teaching of ergonomics. The steps of developing comprised of reviewing literature, revising questionnaire and investigating content validity for 2 rounds by 10 specialists in ergonomic field. The items with low internal consistency were modified and add items to identify level of physical activities and work station were included. Snowball sampling and consensus methods were used. The test was performed two rounds by selecting 5-likert score of two questions of each item in OSCWE. Those questions were “Does the item correspond with the OSCWE's objective?” and “Should this item be in questionnaire?”. Descriptive analysis and Fleiss kappa were calculated for content validity in each item that correspond with the objectives and suitable to be in the new version of OSCWE. Ten specialists who validated the content had averaged years of ergonomic experience 15.3±9.04 years with ranged 5-29 years with educational qualification at doctoral degree. The new version of OSCWE was found that Kappa value of two questions in two rounds were between 0.52-0.61 when assessing all domains. The results showed moderate to substantial agreement. Moreover, Kappa values of two questions in two rounds were between 0.43-0.81 when assessing each domain. The results showed moderate to almost perfect agreement. Exceptionally, Kappa value of work environment of the second question “Should this item be in questionnaire?” of first round was 0.29 which were rated as fair agreement. The average score of each item of OSCWE was found to correspond with the objective and should be included in the questionnaire, except, the personal domain. The mode values of all Items were more than and equal to 3 score which were fair to good level. To be discussed, this questionnaire was developed from the first version of OSCWE which were used in computer workers. The first version had low internal consistency of some items. While this version tried to improve validity of those items which should be more beneficial to determine factors affecting WMSDs, physical activity level, and disorders among computer users in more general population. This study found that OSCWE questionnaire was accepted for its content validity in each item of the five domains. But, some items should be improved for more acceptability level and general use.
Medication error is the most frequent category of errors among others, according to the 2015 annual report of the Taiwan Patient-safety Reporting system (TPR). This type of errors is especially prevalent among hospital inpatients. For those inpatients treated with high-alert medications, any error in their treatments may cause serious adverse outcomes for them. The aim of this study is to review the process of high-alert medications for hospital inpatients with an emphasis on ergonomic perspective. First, a committee was formed consisting of physicians, pharmacists, nurses, and ergonomists. Then, the committee visited four medical institutes to observe their procedures of prescribing, dispensing, and administrating high-alert medications to inpatients. Next, physicians, pharmacists, and nurses in the institutes were interviewed for understanding their daily practices and related issues or problems. Finally, data collected from the observations and interviews were further discussed in the committee to identify room for further improvement in reducing errors and enhancing usability. The observations and interviews focused on the three major stages: physician order entry, pharmacy dispensing, and medication administration. In the stage of physician order entry, Computerized Physician Order Entry (CPOE) systems were used in all the institutes. However, all the systems were different in terms of their functionalities, user interfaces, and databases. Issues about information display, such as the size of order entry window, use of colors and blinks, alert display, and information visualization, were pointed out for further improvement. In the stage of pharmacy dispensing, the major issues were workplace layout and physical environment. Moreover, information could be more visualized. Finally, in the stage of medication administration, multitasking was the common practice and may lead to work overload. Therefore, simplifying procedures or providing aids may improve the work quality of nurses. Furthermore, labels on the medications and the display on the administration devices could be redesigned. Many ergonomic issues were found in the process of high-alert medications for hospital inpatients. These issues could increase mental workload and/or reduce situation awareness of these healthcare practitioners, and consequently might cause errors. In this preliminary study, we identified the problems in the medication process and provided possible solutions. Further empirical research on these identified ergonomic issues in the process of high-alert medications for hospital inpatients should be worthwhile.
Nurses are well-known for their dedication to hard work, performing multiple roles of nurse, manager, partner, parent and so on. To promote their work and life satisfaction, this study examined the interactive effects positive spillover (PSP), negative spillover (NSP), compensation (COM) and segmentation (SEG) caused on the interfaces between multiple roles and work and life satisfaction. In 2015, we collected a total of 910 valid data (male=118 female=792) using the academic online survey service. Questionnaire was composed of the work and life satisfaction items, the Multiple Roles Map (MRM) Questionnaire and demographic items. A logistic regression analysis (LRA) supported the significant relationship between predictor and outcomes and led to five conclusions; (1) The NSP effects were more strongly associated with higher work satisfaction than the PSP effects among male nurses, (2) The PSP effects were more strongly connected with work satisfaction than the NSP effects among female nurses. (3) The male nurses coped with negative events in family and private roles by positive events in nurse role. (4) The female nurses compensated the negative events in nurse roles by positive events in family and private roles. (5) Enrichment of the manager role among male nurses and that of the partner role among female nurses will be meaningful to promote their work and life satisfaction.
Work-related musculoskeletal disorders (WMSDs) have posed a global impact (and concern, therefore) on both individuals' health and industries. In India majority (92%) of the total workforce are in the informal economy, also referred to as the unorganized sector in the country. Among the unorganized sector stone polishing is one where a large number of workers are involved and quite prone to various injuries and accidents. Thirty (30) male stone polishing workers were randomly selected from the Guwahati city of Assam. A modified Nordic questionnaire was used for exploring and assessing their pattern and duration of work, job stress and postural discomfort. The analysis of different working postures of the stone polishing workers was carried out using the Rapid Entire Body Assessment (REBA) method. The commonness of musculoskeletal symptoms in the neck, shoulder, back and knees were found to be very high among the stone polishing workers which may result in a significant number of complaints or injuries in the future. The grand score of REBA has been found high which indicated that the postural load of the workers is prone to develop musculoskeletal problems.
Wearing virtual reality glasses are likely to cause visual fatigue and simulator sickness. In this research, effects of controller and body postures on simulator sickness and visual fatigue are studied by conducting experiments. 32 participants were asked to finish a series tasks while wearing virtual reality glasses. They were asked to fill in questionnaires before and after each experiment to measure visual fatigue and simulator sickness. As a result, participants in standing postures have more severe symptoms of visual fatigue than in sitting postures. And participants who use traditional controllers have more severe symptoms of visual fatigue and simulator sickness than those who use head-movement controller. The result may be useful in design of the interaction of virtual reality glasses.
Neck pain is one of main health problems of office workers. They work with computers in the same position for long period of time. Previous studies show the prevalence of neck pain (45.5%) in office workers. This can lead to direct and indirect costs of health care. It is essential to develop predictors for preventing people from neck pain. Previous studies show that musculoskeletal disorders are related to physical fitness level. Many factors in physical fitness can predict the incident of musculoskeletal disorders.There is still few studies which are specific to neck pain and physical fitness. Therefore, the purpose of the study was to investigate the relation between physical fitness level and prevalence of neck pain in office workers. A preliminary cross-sectional survey study included office workers who work in Faculty of physical therapy, Mahidol University. Participants were advertised with information and advantages of the study. The total of participants in this study were 18 office workers (10 females and 8 males). The test-retest reliability (ICC) of physical fitness tests were between 0.52-0.99. Physical fitness of participants were measured in five domains including 1) range of motion, 2) neck endurance, 3) strengthening of deep neck flexor muscle, 4) grip strength and 5) cardiorespiratory fitness by using cervical range of motion goniometer, neck flexor endurance test, neck flexor strength test by a pressure biofeedback, a hand grip dynamometer and three minutes step test, respectively. Compared the results which norms, subjects can be classified into normal group and below normal group. The Thai version of the modified neck disability index was used for examine the prevalence of neck pain. The neck disability scores were calculated, participants with the score more than 20% of full score were included in neck pain group. Statistic analysis analyzed by SPSS version 20.0. Intraclass correlation coefficient was calculated for test-retest reliability. Descriptive statistics showed that neck strength, neck endurance, cardiorespiratory fitness and range of neck flexion in participants with normal physical fitness level tend to have less prevalence of neck pain than that of participants with below normal physical fitness level.
The aim of this study was to determine PA, sitting time at work and WMSDs in computer workers. We conducted a preliminary cross-sectional study in twenty-one computer workers. Participants age were between 22 to 45 years and were also excluded if they could not stand at work. The online Self-Report Questionnaire on Computer Work-related Expose (OSCWE) was used to assess symptoms of WMSDs during the last 12 months and sitting time at work. Thai Physical Activity Guideline (TPAG) questionnaire was also used to determine physical activity levels and calculate energy expenditure. Twenty-one participants completed the questionnaires. Twenty-eight percent of participants had neck and shoulder WMSDs. Twenty-three percent of participants had PA in level 1 and level 3 defined by TPAG. Energy expenditure of PA and sitting time at work for participants without WMSDs were 1431.48±1721.17 kcal/week and 5.94±1.91 hr/day, respectively. While the above parameters in the WMSDs group were 1324.52±1125.64 kcal/week and 6.83±2.05 hr/day, respectively. Participants without WMSDs had more PA and less sitting time at work than ones who had WMSDs. Although, participants had less PA and more sitting time at work also tended to have WMSDs. Future study should increase the number of subjects to explore the relationship between PA, sitting time at work and WMSDs. Decreasing sitting time at work can also prevent WMSDs in computer workers. Therefore, PA and sitting time at work should be concerned in workplaces.
It is known that worker's performance is related with several factors such as working postures and environmental factors. This study aims to attract attention to the importance of quantifying and assessing factors in a home appliance manufacturing facility. Twenty five assembly line workers are asked to assess environmental conditions and fill out Cornell discomfort survey based on the tasks they perform. Then, video records are analyzed to identify working postures by use of OWAS. Statistical analysis are made to identify whether the factors have a significant effect on the tasks performed or not.
Brazil is the world's leading poultry meat exporter since 2004. The poultry slaughtering workers are exposed to risk factors for work-related upper limb musculoskeletal disorders, such as repetitiveness, high frequency of technical actions, forceful exertions, inadequate posture, insufficient time for recovery, use of tools and exposure to cold temperatures. The aim of this study was to evaluate the risks associated with the repetitive movements of upper limbs in different tasks performed in a poultry slaughterhouse. In the poultry slaughterhouse 1,200 workers slaughtered 100,000 chickens per day during two work shifts. Ten percent of the company's employees were evaluated during the execution of work tasks, using the OCRA Checklist method. Each worker was filmed for a period of 5 minutes. The Student t-test (SPSS 17.0) was used, adopting p≤0.05, in order to compare the risk variable between the sides of the body. The 30 work activities analyzed were from the following sectors: packing (n=12); cutting (n=11); evisceration (n=3); reception (n=2); chiller (n=1); and freezing tunnels (n=1). The average of occupational repetitive actions performed by poultry workers was 64.4±16.1 per minute, representing 9 points in the OCRA's scale (0 to 10 points scale). The average score of OCRA's checklist of all the workstations analyzed was 22.7±5.6 points (moderate risk). The Checklist scores for the right upper limbs (average 22.5 - moderate risk) were significantly higher (p = 0.033) than the left upper limbs (mean of 21.7 - moderate risk), representing a higher risk for the right side of the body. Considering the five risk categories proposed by the OCRA Method, 11 work tasks (37%) were considered high risk, and 19 (63%) presented moderate risk. It is concluded that the majority of the slaughterhouse workers were vulnerable to ergonomic hazards by repetitive movements and to a greater probability of developing upper limb work-related musculoskeletal disorders (>21.5% probability for high risk and 10.8 to 21.5% for moderate risk).
Musculoskeletal disorders (MSDs) are considered to be a major occupational health problem and also affecting quality of work life, medical costs, efficiency at work and productivity in most workplaces. Industrial workers have been identified as high risk for developing MSDs. The purposes of this study were to determine the prevalence and to identify the potential risk hazards on musculoskeletal discomfort occurrence among electronic workers in Thailand. A cross-sectional survey was completed by 321 electronic workers in all departments in a large electronic factory. Data were collected using questionnaires including demographical-occupational data and self-reported musculoskeletal discomfort. Descriptive and binary logistic regression statistics were used to identify ergonomic hazards of reported musculoskeletal discomfort.
Most workers were men (71.40%) with average age of 32.09 years (S.D. = 8.38), and had experience in this factory for 7.76 years (S.D. = 8.20). 76.80% of electronic workers self-reported work-related musculoskeletal discomforts in at least one body part. The most three high prevalence were found at low back (51.4%), followed by lower leg (50%) and shoulder (44%). The workers reported usually working time in a standing posture (74.15%) with average 52.06 minute (S.D. = 2.64). It has been also found that manual material handling was a common task (86.90%) with average weight 8.33 kg. (S.D. = 7.13). Binary logistic regression showed that standing posture (OR=3.75; 95% CI 1.84 to 16.66) was significantly associated with musculoskeletal discomfort (p<0.05).
The prevalence of MSDs among workers in this study is found high. The study revealed that prolonged standing has led to musculoskeletal discomfort among electronics workers, especially in the lower back and lower leg regions. Therefore, work re-design should provide short breaks every hour and muscular stretching to reduce MSDs. Improvement of working condition is recommended in the study to prevent high risk activities at specific complained body parts
Work in the automotive assembly plant is physically strenuous and assembly team members are particularly at risk for developing symptoms of musculoskeletal discomforts (MSDs) compared to other sectors. The main aim of this study was to determine the prevalence rate of musculoskeletal discomforts based on the frequency, severity and performance interference among production assembly team members in an automotive component assembly plant. A cross-sectional study was carried out among the production assembly team members who performed manual assembly welding task. The Cornell Musculoskeletal Disorders Questionnaire (CMDQ) data sheets were used in interview with the assembly team members to obtain the prevalence of MSDs. The prevalence of pain in the upper back, lower back, right shoulder and right wrist have been reported to be higher in comparison with pain in other parts of the body. The current study identified the severe musculoskeletal discomfort allies with production assembly line. Assembly team member's lines 4 were reported high mean frequency discomfort, severely discomfort and interfered assembling task performance. It has been discovered; nonetheless, that assembly team member's assembling task performance has interfered with lower back pain. MSD's survey appeared to be very helpful to screen the production assembly team member's health,well-being and performance. The results are also useful for assessing the ergonomics risks factors in the future study.
A console of a submarine is a collection of user interfaces composed of control devices and two vertically installed displays. Since console operators receive most visual information from these displays for a long time, it may cause musculoskeletal disorders and psychological discomfort if the screen is not in the right position. Therefore, the aim of this study is to derive optimal design values for the position and tilting angle of displays. We identified the environmental constraints of control room and the visual angle of the operators. In addition, we considered the physical characteristics of target user population. Thus, we used anthropometric data of Korean males aged from 20s to 30s, who are representative user segments that operates the console. Tasks were divided into ‘direction’ tasks that operators usually perform, and ‘detection’ tasks, which should be performed in case of emergencies. The variables of monitor height, maximum vertical height, work surface height, eye height, and distance between eye and monitor were selected, and conditional equations were established with consideration of design factors and environmental constraints. With these equations, the optimal value was derived through a GRG (Generalized Reduced Gradient) method. After, we evaluated the appropriateness of the proposed optimal values with a full-scale mockup of a console. 10 ergonomics experts conducted usability test, and reaction time (RT) as well as electromyography (EMG) activity of the cervical vertebral were measured during the experiment. As a result, participants reacted within a fairly short time with little fatigue on the cervical vertebral. Overall, we successfully suggested the optimal ranges of tilting angles for two vertically arranged monitors while considering context-of-use, anthropometric characteristics of South Koreans, and human visual characteristics.
The paper attempts to highlight indigenous Jugaad practices of the people of villages in India. Jugaad has played an important role in solving problems. The style of innovations is defined by the kind of resource available and the availability of optional resources. It also outlines some conventional techniques and tools that are essentially found in the rural part of India. The paper presents two broad areas of product innovation in villages and towns of India. One being the design innovation and the other being the bare necessity of functional expectation for the masses. It includes a classification of these local innovations termed as Jugaad according to the type whether incremental, modular, architectural or radical. The innovation in India originated many centuries ago from the time of Indus valley civilization. Villages and towns remained distant to the available technology which is more enjoyed in the urban areas in terms of sharing the benefits of laboratory advancements of technology and innovations. Study of some Jugaad products such as knife, lamps etc. provide origin and evolution of Jugaad products. It also presents the different categories of product with regards to functionality technique and resources used. Jugaad innovators sense and respond to the social and environmental changes. The financial constraints, absence of need of procuring certification & validity, lack of cut throat competitions among other factors put an easier and simpler route of execution of Jugaad ideas. Jugaad presents creativity in its blatant and crude form. Jugaad innovations consider the affordability of the product or services in terms of the low earning villagers and towners. Being indigenous in nature such innovations are cheaper and exhibit less dependence on expensive resources. People with sufficient higher spending power often purchase branded products ranging from agriculture to household utility furniture. Much of village population depends on their livelihood they earn from agriculture. Agriculture is the main occupation in most rural part of India. Which indicates that most villages continue to flourish with their indigenous tools and techniques. However increased migration may potentially disturb the practice of indigenous innovations to some extent.