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This report introduces the AF PREMIER Program. The primary goal of the PREMIER program is to minimize the negative impact on AF mission accomplishment by preventing work-related musculoskeletal disorders (WMD) among AF employees. The AF PREMIER program consists of a series of modules designed to anticipate, recognize, evaluate, and control ergonomic risk factors associated with WMD development. This report describes the overall philosophy of the AF PREMIER program and provides detailed management guidelines for implementation of the program.

Background & Objective (s) Upper extremities musculoskeletal disorders (UEMSDs) are referred as the most pervasive and significant problem in textile industries worldwide. Therefore, this study was conducted to assess the ergonomic risk factors of UEMSDs by Comprehensive Exposure Index (CEI) in a textile industry. Materials & Methods 425 accidentally-sampled workers of Ghaemshahre textile industry (North of Iran) were studied in a cross-sectional study. A combined method including: Interviews (to gain workers’ personal characteristics and understand job processes), Nordic Musculoskeletal Questionnaire (NMQ; to obtain UEMSDs pain symptoms and signs prevalence), Hierarchical Job Analysis (HJA; to analyse jobs before assessment) and Comprehensive Exposure Index (CEI; to assess the ergonomic risk factor of UEMSDs) were used and the gathered data were analysed. Results Percentage pain symptoms in hand & fingers, wrist, forearm, elbow, arm, and shoulder were 83.61%, 78.28%, 71.39%, 57.09%, 41.22%, and 24.18% respectively. There were significant correlation between prevalence of hand & fingers musculoskeletal disorders with workers’ age, job experience, and stature ( p ). CEI revealed that 11.28% of tasks posed on level 1 (Safe level), 22.61% of tasks posed on level 2 (uncertain level), 47.12% of tasks located on level 3 (slight risk level), and 18.99% of tasks posed on level 4 (significant risk level). There were significant associations between CEI scores and pain symptoms prevalence of hand & fingers and wrists ( P 5). Discussion and Conclusions Most repetitive tasks of textile industry feature ergonomic risk factors that can induce UEMSDs. The CEI model was found to be a sensitive model to assess the ergonomic risk factor causing UEMSDs in textile industries and any changes in exposure before and after ergonomic interventions.

Improper application of an ergonomic analysis tool increases the likelihood of high-risk jobs not being detected, thus jeopardising worker’s health. Likewise, significant time and cost may be incurred by redesigning jobs improperly identified as high risk. Utah Intelligent Data Driven Ergonomic Assessment System (IDDEAS) is an expert system that aggregates the outputs of multiple analysis tools to create a more predictive ergonomic analysis tool. Rules in the expert system were optimised by processing health outcome data from hundreds of jobs and analysing the resulting relationship between the system’s prediction and the known health outcomes. IDDEAS appears to improve in predictive ability with addition of expert knowledge and to be more accurate at predicting the level of risk than individual ergonomic analysis tools used alone. The study also provides insight into methods of quantifying health outcomes and analysis tool outputs for use in software systems that integrate or compare ergonomic information.

EK. has worked in the clinical laboratory of a large medical center for 14 years. Her duties include processing and testing specimens, and entering results into a computer. She uses a variety of equipment for these tasks, including a microscope, pipette, and cell counter. E.K. has noted numbness and tingling in both thumbs and index fingers for the past few years, which currently has become constant over recent months. She reports difficulty gripping objects and a loss of grip strength. Last week, she dropped an entire rack of test tubes. This prompted her supervisor to refer her to employee health for evaluation. During her visit, she is nonchalant about her symptoms, noting that everyone in her lab has lots of “aches and pains” and that “it's part of the job.” On examination, she has severe hypothenar atrophy, decreased range of motion of the thumb carpometacarpal joints bilaterally, decreased grip strength, and a loss of sensation to two point discrimination in a medial nerve distribution.

Summary Objectives The aim of the study was to investigate the connections between voice ergonomic risk factors found in classrooms and voice-related problems in teachers. Methods Voice ergonomic assessment was performed in 39 classrooms in 14 elementary schools by means of a Voice Ergonomic Assessment in Work Environment—Handbook and Checklist. The voice ergonomic risk factors assessed included working culture, noise, indoor air quality, working posture, stress, and access to a sound amplifier. Teachers from the above-mentioned classrooms reported their voice symptoms, respiratory tract diseases, and completed a Voice Handicap Index (VHI). Results The more voice ergonomic risk factors found in the classroom the higher were the teachers' total scores on voice symptoms and VHI. Stress was the factor that correlated most strongly with voice symptoms. Poor indoor air quality increased the occurrence of laryngitis. Conclusions Voice ergonomics were poor in the classrooms studied and voice ergonomic risk factors affected the voice. It is important to convey information on voice ergonomics to education administrators and those responsible for school planning and taking care of school buildings.

Objectives to determine the magnitude, distribution and associated ergonomic factors of radial styloid tenosynovitis among electronic assembly workers in Thailand. Methods the design was a cross-sectional study. 591 of 853 workers in an electronic and electrical appliance assembly factory in Bangkok, Thailand, participated in the study during October 2010 to January 2011. The self-administered questionnaire consisted of demographic data and ergonomic factors. The clinical examination was done by a physician for radial styloid tenosynovitis diagnosis. The criteria for diagnosis came from the consensus by a group of orthopaedists. The associated ergonomic factors of radial styloid tenosynovitis were analysed by multiple logistic regression. Results the prevalence of radial styloid tenosynovitis in electronic assembly workers was 13.08% (95% CI 10.23 to 15.92%). They were aged 18–30 years. 97.46% were female. After adjustment for age, gender, education and body mass index, the adjusted ORs to develop radial styloid tenosynovitis for the following ergonomic factors were: forceful exertion of wrist 1.78 (95% CI 1.06 to 2.99), awkward posture of wrist 2.37 (95% CI 1.28 to 4.36) and contact stress at wrists 1.75 (95% CI 1.02 to 3.00). However, there was no association between repetitive motion and radial styloid tenosynovitis. Conclusions radial styloid tenosynovitis was the most common upper extremities musculoskeletal disease in electronic assembly workers. The ergonomic risk factors for this problem were forceful exertion, awkward posture and contact stress. The relevant parties should provide ergonomic training for these workers.

Manufacturing in developing economies continue to be labour intensive owing to its cost benefits. Productivity improvement in this circumstance is brought about by continuous evaluation of manual work for ergonomic risks and taking corrective actions. Existing tools for risk assessment seek to measure risk in isolation while risk often depends on several factors such as posture, loads, injury proneness of a job and environmental factors (EFs) (temperature, lighting conditions, etc.). In the absence of an integrated measurement tool for ergonomic risk assessment, we propose a composite measure called RBG risk scale. It provides a single measure of the ergonomic assessment in terms of several factors (e.g. posture, biomechanical forces, environmental, etc.) collectively contributing to ergonomic impairments. This integrated score provides a clearer picture of the risk involved in the job and hence it can be used as a basis for prioritising operations for ergonomic interventions.

A two-page checklist for determining the presence of ergonomic risk factors associated with the development of upper extremity cumulative trauma disorders (e.g., repetitiveness, local mechanical contact stresses, forceful manual exertions, awkward postures, and hand tool usage) was developed and evaluated as part of a joint labour-management ergonomics intervention programme. This checklist was used by plant personnel at four work sites to assess the presence of upper extremity risk factors in 335 manufacturing and warehouse jobs. In addition, results generated by the checklist were compared to the results of ergonomic analyses performed by persons with advanced training (Masters degree) in occupational ergonomics for a subset of 51 jobs. Most of the jobs included in the survey were found to have significant exposures to upper extremity risk factors. Awkward work postures were common, with 90% of the jobs requiring wrist deviations outside the neutral range-of-motion. The jobs were also highly repetitive and frequently required workers to exert high hand forces. Results generated by the checklist were generally in agreement with results generated by the ergonomic analysts; however, the checklist was found to be more sensitive in identifying the presence of risk factors. The checklist was found to be an effective rapid-screening instrument for identifying jobs that expose workers to potentially harmful ergonomic stresses. However, the checklist methodology did not include sufficient documentation of work methods to identify specific job attributes associated with these exposures.

It is the intent of the work to achieve the ergonomic effective design of a workstation belonging to an industrial plant operating in the field of mechanical parts production. To this end, the authors propose an approach based on the integration of modelling and simulation tools and several ergonomic standards. Modelling and simulation tools are used to implement a three-dimensional environment capable of recreating, with satisfactory accuracy, the evolution over the time of the real workstation. The ergonomic standards are accomplished for evaluating and analysing the ergonomic risk level within the system being considered. Workstation modifications are incorporated in the simulation model and the effects (ergonomic risk level) of those changes are analysed for designing an improved workstation configuration in terms of interaction between operators and their industrial working environment.

After several years of political controversy, the Occupational Safety & Health Administration has proposed a new standard designed to protect workers from repetitive stress injuries. The proposal would require companies to make one person responsible for ergonomic issues, to supply ergonomic resources and training on their use, to inform workers of ergonomic risk factors and symptoms of musculoskeletal disorders, and to set up a disability reporting system. Under the proposed standard, a company would have to establish a prevention program if just one worker suffers an ergonomic disability. OSHA claims its standard would be flexible and inexpensive. "This proposal includes some unique provisions to expand flexibility," says Charles N. Jeffress, assistant secretary of labor for occupational safety and health. "We've given employers a quick-fix option and included a grandfather clause, both designed to limit what employers need to do while effectively protecting workers." OSHA estimates the standard would c...

Musculoskeletal disorders (MSDs) have been common complaints among workers involved in static work or tasks requiring the repetitive motion of the upper limbs and prolonged computer work. Call center workers are the one group which may impact on chronic musculoskeletal health problems. Therefore, the aim of this study was to assess ergonomics risk for MSDs in work environment among call center workers. This was a survey study conducted among 216 call center workers in Khon Kaen province, Thailand. Call center workers who had experience jobs more than 6 months, working time at least 32 hours per week with computer at least 4 hours per days. Data were collected by the Rapid Office Strain Assessment (ROSA) which measured the sitting posture, workstation (chair height, pan depth, armrests, and back support), computer (monitor, mouse and keyboard), telephone and duration of spending time for each posture or activity. From ROSA, there were 4 levels of ergonomics risk classification (low, medium, high, very high). The results of this study showed that the call center workers were only at 2 level of risk (high and medium). The majority of the call center workers were at high risk level (score 5-7 points) for 52.3% (mean score 5.3, 95%CI: 5.2-5.4). The medium risk level (score 3-4 points) was 47.7% (mean score 3.6, 95%CI: 3.5-3.7). The top three highest frequencies of score of ergonomics risk were 5 points, followed by 4 points and 3 points which were at 37.5%, 28.2% and 19.4%, respectively. The mean score of that risk was 4.5 (95% CI: 4.4-4.6). By using the ROSA, this study showed that most of the call center workers were exposed to the high ergonomics risk for MSDs development. For prevention of MSDs, there should be ergonomics training for workers to be aware of ergonomics factors in the office. The personal working behaviors and the design of the workstations should be improved based on the ergonomics principles.

This research presents a design proposal for extremes where men and women perform similar tasks in the same workstations. Within assembly lines hydraulic presses that allow to be adjusted to different heights are used. However, at the initial workstation of the cell production, a high fixed workstation is used. In addition, workers have to handle axis of different dimensions. For example, the shortest is 50 centimeters while the longest is 90 centimeters. Medical service department has received constant complaints from workers assigned to this workstation, which reported mostly musculoskeletal discomfort in shoulders, neck and back. The objective of this research is to develop a new workstation design that allows adjusting its dimensions according to the workeŕs statures and parts sizes used in the assembly lines. Ergonomic assessment was developed applying the Muscular Fatigue Assessment (MFA) and Biomechanics analysis before and after workstation implementation. The MFA method shows very high levels of ergonomic risk on shoulders, neck, back, and hands. While the biomechanical evaluation shows overload on shoulder (321%), elbow (490%), L5/S1 (518%), and hip (118%). A workstation that reduces risk levels from very high to medium is designed and also eliminates overloading in shoulder and ankle. This is confirmed by the methods of assessment after implementation of the new design workstation.

Assembly lines are associated with health risk and musculoskeletal disorders, particularly in the upper limbs. The aim of this study was to analyze three risk factors of posture, duration and force by using the postural ergonomic risk assessment (PERA) method in the workers of the assembly unit of automobile parts. Material and Methods: This descriptive cross-sectional study was conducted in the assembly unit of one of the auto parts manufacturing industries. Using the occupational task analysis method, task identified in one hierarchical task analysis (HTA) was divided into a set of sub-tasks. Risk factors of posture, duration and force were assessed by PERA method for each task. Results­: Based on hierarchical task analysis, the vehicle assembly task included four sub-tasks of deburring, washing, vacuum testing and packaging which consisted of a total of 15 operations. Based on the risk factor analysis, we found the greatest risk of force in loading operations and the most awkward posture in sub-task of deburring and packaging. The risk level was estimated high and unacceptable in all three sub-tasks of washing, vacuum testing, and packaging. Conclusion: Factors of force, posture and duration of work contributed to unacceptable risk in the loading operations of the cylinder head on the pallet and placing it inside the carton. Using tables with adjustable height (reducing the vertical distance between origin and destination) and rotating plates at all angles, together with reducing the exposure time to risk factors by rotation programs for workforces can prevent forward and lateral trunk and neck bending and reduce unacceptable risk levels.

This work examines a balancing problem wherein the objective is to minimize both the ergonomic risk dispersion between the set of workstations of a mixed-model assembly line and the risk level of the workstation with the greatest ergonomic factor. A greedy randomized adaptive search procedure (GRASP) procedure is proposed to achieve these two objectives simultaneously. This new procedure is compared against two mixed integer linear programs: the MILP-1 model that minimizes the maximum ergonomic risk of the assembly line and the MILP-2 model that minimizes the average deviation from ergonomic risks of the set of workstations on the line. The results from the case study based on the automotive sector indicate that the proposed GRASP procedure is a very competitive and promising tool for further research.

In this paper, we present an extension to the TSALB problem (Time and Space constrained Assembly Line Balancing) with ergonomic risk restrictions. This ergonomic risk is defi ned from the task durations and their categories regarding to the risk factor for the workers. A study is presented through a case linked to an engine assembly line in the Automobile industry, considering variable demand.

This work addresses a balancing problem approach whose objective is to minimizing the ergonomic risk dispersion between the set of workstations of a mixed-model assembly line and the risk level of the workstation with the greatest hazard. A GRASP procedure is proposed to achieve these two challenges simultaneously. This new procedure is compared with two Mixed Integer Linear Programs, the MILP-1 that minimizes the maximum ergonomic risk of the assembly line, and the MILP-2 that minimizes the average deviation from ergonomic risks of the set of workstations of the line. The results from the case study linked with the automotive sector indicate that the proposed GRASP is a very competitive and promising tool for further researches.

BackgroundThe aim of this pilot study was to analyze postures during the work of neurologists with respect to their occupational activities.MethodsA total data material of 64.8 h (3885.74 min) of nine (three m/six f) neurologists (assistant physicians) was collected. Kinematic data were collected using the CUELA system (electro-goniometry). In addition, the occupational tasks performed on-site were subject to a detailed objective activity analysis. All activities were assigned to the categories “Office activities” (I), “Measures on patients” (II) and “Other activities” (III). The angle values of each body region (evaluation parameters) were evaluated according to ergonomic ISO standards.ResultsOnly 3.4% of the working hours were spent with (II), while 50.8% of time was spent with (I) and 45.8% with (III). All tasks of category (II) revealed an increased ergonomic risk to the head, neck, trunk and back areas. During category (I) especially neck and back movements in the sagittal plane showed higher ergonomic risk levels.ConclusionDespite frequently performed awkward body positions in (II), the ergonomic risk is considered as rather low, since the percentage time share totaled only 3.4%. As a result, “Office activities” have been detected as high predictor to cause stress load on the musculoskeletal system in the daily work of neurologists.

In this paper we propose to incorporate some working conditions to the assembly lines. For this, used a mathematical model to solve the assembly line balancing problem whose objective is minimizing the ergonomic risk, imposing the limitation of the cycle time, number of workstations and the maximum linear area for each station. A study is presented through a case study that corresponds to an assembly line from Nissan’s plant in Barcelona.

We present a new mathematical model for the assembly line balancing problem with the objective of maximizing the line comfort to operators. Besides minimizing discrepancies between the ergonomic risks of workstations, balancing is subject to temporal and spatial conditions for the workstations. To evaluate the performance of the proposed model, we compare it with other mathematical model whose objective is minimizing the maximum ergonomic risk of a mixed-model assembly line. To compare the models, a case study linked to Nissan’s engine plant in Barcelona (NMISA, Nissan Motor Ibérica – BCN).

A cross-sectional survey of semiconductor factories was conducted to identify the ergonomic risk factors in the work processes, the prevalence of body pain among workers, and the relationship between body pain and work processes. A total of 906 women semiconductor workers took part in the study. In wafer preparation and polishing, a combination of lifting weights and prolonged standing might have led to high pain prevalences in the low back (35.0% wafer preparation, 41.7% wafer polishing) and lower limbs (90.0% wafer preparation, 66.7% wafer polishing). Semiconductor front of line workers, who mostly walked around to operate machines in clean rooms, had the lowest prevalences of body pain. Semiconductor assembly middle of line workers, especially the molding workers, who did frequent lifting, had high pain prevalences in the neck/shoulders (54.8%) and upper back (43.5 %). In the semiconductor assembly end of line work section, chip inspection workers who were exposed to prolonged sitting without back support had high prevalences of neck/shoulder (62.2%) and upper back pain (50.0%), while chip testing workers who had to climb steps to load units had a high prevalence of lower limb pain (68.0%). Workers in the assembly of electronic components, carrying out repetitive tasks with hands and fingers, and standing in awkward postures had high pain prevalences in the neck/shoulders (61.5%), arms (38.5%), and hands/wrists (30.8%).

The detection and prevention of workers’ body straining postures and other stressing conditions within the work environment, supports establishing occupational safety and promoting well being and sustainability at work. Developed methods towards this aim typically rely on combining highly ergonomic workplaces and expensive monitoring mechanisms including wearable devices. In this work, we demonstrate how the input from low-cost sensors, specifically, passive camera sensors installed in a real manufacturing workplace, and smartwatches used by the workers can provide useful feedback on the workers’ conditions and can yield key indicators for the prevention of work-related musculo-skeletal disorders (WMSD) and physical fatigue. To this end, we study the ability to assess the risk for physical strain of workers online during work activities based on the classification of ergonomically sub-optimal working postures using visual information, the correlation and fusion of these estimations with synchronous worker heart rate data, as well as the prediction of near-future heart rate using deep learning-based techniques. Moreover, a new multi-modal dataset of video and heart rate data captured in a real manufacturing workplace during car door assembly activities is introduced. The experimental results show the efficiency of the proposed approach that exceeds 70% of classification rate based on the F1 score measure using a set of over 300 annotated video clips of real line workers during work activities. In addition a time lagging correlation between the estimated ergonomic risks for physical strain and high heart rate was assessed using a larger dataset of synchronous visual and heart rate data sequences. The statistical analysis revealed that imposing increased strain to body parts will results in an increase to the heart rate after 100–120 s. This finding is used to improve the short term forecasting of worker’s cardiovascular activity for the next 10 to 30 s by fusing the heart rate data with the estimated ergonomic risks for physical strain and ultimately to train better predictive models for worker fatigue

In early mobilization context as also for any type of critically ill patient mobility, there are different levels of patients' participation during the activity, going from total dependence to independence. In this sense, two aspects should be considered as the efficacy of safe procedures to the patient as well as for the health care team in order to minimize ergonomic risks. This ergonomic risk can be tracked through a specific scale, although so far there are no evidence of this ergonomic risk in critically ill patients.