Ergonomic Assessment Methods Research Articles

Using the INRS QECPT method for ergonomic assessment and prevention strategies in an Algerian maternity ward

Introduction: Physical workload is a significant challenge in maternity wards, where healthcare workers face intense demands such as patient handling, prolonged postures, and repetitive efforts. This study, conducted in an Algerian maternity ward, uses the INRS (National Institute for Research and Safety) method to evaluate physical workload, identify biomechanical, organizational, and environmental risks, and propose improvement strategies. Methods: This study followed a structured three-step approach. First, risks were identified and prioritized using ergonomic indicators to highlight critical situations. Second, a detailed evaluation of physical workload was conducted based on five dimensions: physical effort, staffing levels, temporal constraints, organizational factors, and environmental conditions. Risks were stratified into moderate and high levels to focus on key areas for intervention. Finally, preventive strategies were proposed to reduce constraints and improve working conditions for healthcare workers. Results: Out of 31 work situations analyzed, 47.2% exhibited moderate to high-risk levels. The gynecology, high-risk pregnancy, and neonatology units concentrated critical constraints, including prolonged postures and intense physical efforts. Conclusion: The study highlights key priorities such as improving ergonomic equipment and reorganizing workflows to reduce physical strain and preserve healthcare workers’ health while ensuring quality patient care. This provides a foundation for targeted preventive strategies.

Fuzzy expert system for ergonomic assembly line worker assignment and balancing problem under uncertainty

ABSTRACT In the era of Industry 5.0, there is a significant gap in addressing ergonomic risks and imprecise task times in manufacturing systems. This study aims to fill this gap by extending the ergonomic assembly line balancing problem with worker assignment. It employs a novel two-phase framework combining a constructive heuristic for feasibility with a unique ergonomic assessment method developed through a fuzzy expert system. Validated using 96 synthesized numerical instances, the proposed method addresses the scarcity of fuzzy and ergonomic-oriented data in benchmarks. Then, computational results are thoroughly analyzed to evaluate the method’s performance and identify potential areas for further research. The proposed optimization method provided high-quality solutions with a majority demonstrating low ergonomic risk and high worker safety, contributing to an overall improvement in ergonomic conditions. The integration of fuzzy expert system and advanced optimization techniques yields a robust framework for achieving a safer and more efficient manufacturing environment.

Pengujian Ergonomi Berdasarkan SNI 9011:2021 dan ROSA Serta Evaluasi Lingkungan Kerja Perkantoran Berdasarkan Peraturan Menteri Kesehatan Nomor 48 Tahun 2016 di Fakultas Teknik Unsoed

Office environments, as one of workplace, are inherently associated with potential occupational hazards that may impact the health and safety of individuals within them. According to the Ministry of Health of Indonesia Regulation No. 48 of 2016, office spaces are required to meet specific physical conditions, taking into aspects such as lighting, noise levels, air temperature, and humidity within the work environment. Various issues have been identified at the Faculty of Engineering, Universitas Jenderal Soedirman, such as malfunctioning some of air condition units, inadequate lighting, noise pollution from vehicular traffic, and complaints regarding workers' postures. Office workers are susceptible to ergonomic risks, particularly musculoskeletal disorders due to work activities (GOTRAK). This research aims to evaluate the compliance with the Ministry of Health of Indonesia Regulation No. 48 of 2016 by assessing the work environment and adhering to the standards outlined in SNI 9011:2021, which pertains to the Measurement and Evaluation of Potential Ergonomic Hazards in the Workplace. To strengthen the data and ensure the identification of potential ergonomic hazards in office settings, ergonomic assessment methods such as the Rapid Office Strain Assessment (ROSA) can be employed. The objective of this study is to measure physical environmental parameters such as lighting intensity, noise levels, and air temperature, identify GOTRAK-related complaints based on SNI 9011:2021, and provide recommendations for improvements in accordance with the Ministry of Health of Indonesia Regulation No. 48 of 2016 and SNI 9011:2021.

Data-driven ergonomic assessment of construction workers

Automating ergonomic assessment improves both objectivity and cost-effectiveness. However, existing ergonomic scales remain susceptible to inaccuracy and insensitivity when assessing diversified construction activities. This susceptibility stems from the unreliable ranges, sharp boundaries, and oversimplified binary rules within conventional joint-level assessment rules, coupled with the restricted transformation rules to integer input/output. This paper presents a data-driven ergonomic assessment method grounded in statistical data from Construction Motion Data Library (CML) dataset, comprising: 1) Developing joint-level scoring models to primarily improve accuracy through leveraging Heuristics Gaussian Cloud Transformation (H-GCT), and 2) Designing fuzzy inference mechanism to enhance sensitivity through retaining risk information during transformation across levels. Subsequently, a three-step validation confirms accurate risk identification, sensitive risk feedback, and positive correlation with previous methods, contributing to occupational health and safety management. Future research could enhance the method by expanding the pose dataset, recruiting more participants, and refining the 3D pose estimation.

Comparison of multi-task ergonomic assessment methods for risk of upper extremity and low back musculoskeletal disorders

Work-related musculoskeletal disorder of upper extremity multi-task assessment methods (Revised Strain Index [RSI], Distal Upper Extremity Tool [DUET]) and manual handling multi-task assessment methods (Revised NIOSH Lifting Equation [RNLE], Lifting Fatigue Failure Tool [LiFFT]) were compared. RSI and DUET showed a strong correlation (rs = 0.933, p < 0.001) where increasing risk factor exposure resulted in increasing outputs for both methods. RSI and DUET demonstrated fair agreement (κ = 0.299) in how the two methods classified outputs into risk categories (high, moderate or low) when assessing the same tasks. The RNLE and LiFFT showed a strong correlation (rs = 0.903, p = 0.001) where increasing risk factor exposure resulted in increasing outputs, and moderate agreement (κ = 0.574) in classifying the outputs into risk categories (high, moderate or low) when assessing the same tasks. The multi-task assessment methods provide consistent output magnitude rankings in terms of increasing exposure, however some differences exist between how different methods classify the outputs into risk categories.

Postural physical burden of street vendors in Boyacá, Colombia

It was performed an observational study of transversal cut with a descriptive approach with the objective of evaluating the postural physical burden of fruits and vegetables street vendors in Boyacá, Colombia through the ergonomic assessment method REBA. The chosen population of the study was fifteen workers from a street vendors association in Sogamoso city. The results show that the vendors have a high and very high risk of generating musculoskeletal disorders due to the postural burden they are exposed to. Some recommendations were made to decrease the physical burden based on four strategic angles: education, social responsibility, self-learning and engineering control at workplaces. This brings to the conclusion that the problematic perceived in this population of workers from the informal sector is similar to the one seen in other regions and countries; it is recommended the active participation for developing policies that allow to improve their work conditions and life quality.

Model-driven evaluation of exoskeletons for efficient traction battery dismantling

The disassembly of traction batteries is primarily performed manually due to the difficulty of implementing automation solutions, mainly because of the large number of variants. As a result of the lack of automation, employees are frequently exposed to heavy loads and unergonomic postures, which can lead to work-related musculoskeletal disorders. This paper utilizes a modeling approach with the software “emaWorkDesigner” to evaluate the ergonomics and feasibility of exoskeletons in facilitating and improving the manual disassembly of traction batteries. The Ergonomic Assessment Work Sheet EAWS is applied as ergonomic assessment method. EAWS section criteria are analyzed to investigate the potential use of exoskeletons to support the workers. The assessment is conducted based on the example of the first disassembly step, which is the removal of the tray cover. Finally, the study concludes with recommendations and areas of future research for the traction battery disassembly in industrial applications.

Online Ergonomic Evaluation in Realistic Manual Material Handling Task: Proof of Concept.

Work-related musculoskeletal disorders are globally one of the leading causes of work-related injuries. They significantly impact worker health and business costs. Work task ergonomic risk indices have been developed that use observational assessments to identify potential injuries, and allow safety managers to promptly intervene to mitigate the risks. However, these assessments are very subjective and difficult to perform in real time. This work provides a technique that can digitalize this process by developing an online algorithm to calculate the NIOSH index and provide additional data for ergonomic risk assessment. The method is based on the use of inertial sensors, which are easily found commercially and can be integrated into the industrial environment without any other sensing technology. This preliminary study demonstrates the effectiveness of the first version of the Online Lifting Index (On-LI) algorithm on a common industrial logistic task. The effectiveness is compared to the standard ergonomic assessment method. The results report an average error of 3.6% compared to the NIOSH parameters used to calculate the ergonomic risk and a relative error of the Lifting Index of 2.8% when compared to observational methods.

Comparison of ACGIH lifting threshold limit values to validated low back disorder lifting assessment methods outcomes.

Work-related low back pain (LBP) increases the workforce disability and healthcare costs. This study evaluated the LBD risk level associated with handling the ACGIH TLVs in lifting tasks corresponding to various horizontal and vertical zones. The aim of this study was to compare the low-risk ACGIH TLV to risk outcomes from various validated lifting assessment methods, including the OSU LBD Risk Model, NIOSH Lifting Equation, and LiFFT. Twenty-four subjects were recruited for this study to perform various lifting conditions. The various ergonomic assessment methods were then used to obtain the risk assessment outcomes. The selected assessment methods showed that the ACGIH-defined TLVs are associated with less than high-risk for LBD for all the assessed tasks. The findings showed a moderate agreement (Kendall's W = 0.477) among the various assessment methods risk outcomes. The highest correlation (ρ= 0.886) was observed between the NIOSH Lifting Equation and LiFFT methods risk assessment outcomes. The findings showed that ACGIH-defined TLVs possesses less than high-risk for LBD. The outcomes of the selected ergonomic assessment methods moderately agree to each other.

Integrated lean and ergonomic assessment for the planning of human-centered factories

This research proposes an approach for evaluating human-centered work processes by combining Value Stream Mapping and ergonomic assessment of physical workload. Value Stream Mapping is a method used to create a visual representation of the flow of materials and information required to deliver a product, and aids in identifying potential bottlenecks and other constraints. However, it does not consider the effect of physical ergonomics on process execution and planning. To bridge this gap, the Ergonomic Assessment Worksheet screening tool is used to gain insight into unfavourable physical workload situations. The proposed approach follows five main steps: (i) scope definition, (ii) Value Stream Map, (iii) time study, (iv) ergonomic assessment, (v) combined analysis. A case study is conducted at a bicycle manufacturer to demonstrate the effectiveness of the approach in quantifying the impact of physical ergonomics on process performance. The method enables a systematic analysis of process chains to identify critical steps from both lean and ergonomic perspectives, emphasizing the importance of worker's physical well-being and the ability of ergonomic assessment methods to enhance Value Stream Maps.

Nail job and women’s health: Assessment of ergonomics and occupational hazards

BACKGROUND: The nail job is a new occupation in which the number of people who choose this job is rising. Therefore, the harmful hazards affecting the health of the practitioners should be taken into account. OBJECTIVE: The purpose of this study is to evaluate the ergonomics and occupational health hazards among nail technicians in Iranian society. METHODS: The self-administered questionnaire, the Nordic Musculoskeletal Questionnaire and Novel Ergonomic Postural Assessment (NERPA) method were used to gather data from 80 female nail technicians who participated in this study. RESULTS: More than half of the participants (67.6%) complained of coughing and eye irritation (70%) which was the most frequently reported irritation. The final score of the NERPA was at a high-risk level and the neck pain (63.8%) was the highest in comparison with other parts of the body. There was a significant relationship between activity type with disorder in the neck, elbow, hip, knee, and ankle. Lighting intensity was not significantly associated with musculoskeletal disorders. CONCLUSIONS: Concerning the low work experience, the prevalence of musculoskeletal disorders and, respiratory complaints is high. Hence, the attention of policy-makers to the safety and hygiene issues of women in this occupation is necessary by setting guidelines and considering inspections of occupational health and safety professionals.

VR–MOCAP-Enabled Ergonomic Risk Assessment of Workstation Prototypes in Offsite Construction

Workers in offsite construction facilities are often exposed to repetitive motion and awkward body postures that are associated with the risk of developing work-related musculoskeletal disorders despite the use of automated equipment on production lines. To reduce the exposure to these risks, an investigation of the physical demands that workstations impose on workers’ bodies is needed. Since traditional methods used to collect human body motions have limitations, such as workplace interruptions and biased results due to subjective observation, this paper proposes a virtual reality (VR)–motion capture (MOCAP)-based ergonomic assessment method to evaluate ergonomic risks in a laboratory setting during the design phase of workstation development. It is expected that the number of iterations of physical workstation prototypes would be reduced if ergonomic risk ratings are identified proactively in the initial phases of workstation design, which would thereby reduce the cost and time required to develop and implement an improved workstation design. The present study includes a feasibility analysis of the proposed method in which participants representative of specific percentiles of the population based on their physical stature were invited to voluntarily participate in a research experiment. The results obtained demonstrate that the proposed method can successfully simulate the elemental motions, referred to as therbligs, of reaching and positioning (Pearson’s correlation coefficient is found to equal 0.80 and 0.94, respectively), while the simulation of the assembling therblig requires further investigation. The contribution of this study is a virtual reality–motion captured-enabled ergonomic risk assessment method applied to workstation design for offsite construction production lines. In addition, the deployment of the proposed method allows a holistic ergonomic assessment that considers objective and subjective parameters.

Ergonomic Assessment Method of Risk Factors for Musculoskeletal Disorders Associated with Sitting Postures

Musculoskeletal disorders (MSDs) are associated with sitting postures. The assessment and prevention of risk factors for workplace exposure are indispensable aspects of reducing the occurrence of MSDs. This paper proposes an ergonomic assessment method of risk factors for MSDs associated with sitting postures in the actual working conditions. A Kinect sensor with the RULA method was primarily used to collect the data and evaluate the relevant postures. The results obtained were compared with the evaluation results by a human expert. Additionally, we verified the capability and effectiveness of this method. A program system for human joint recognition and acquisition was implemented. The results indicated that the Kinect joint data is generally accurate and can adequately complete the RULA evaluation table. The results from the front and right-hand side obtained by the Kinect were consistent with the results of the expert evaluation, and no significant difference was observed between them ([Formula: see text]). However, when the participants faced the Kinect, the sensor performed better, and the evaluation result was more accurate. A high consistency was observed between the evaluation results obtained from the front and the expert (proportion agreement [Formula: see text], Cohen’s [Formula: see text]). Only a slight consistency was observed between the evaluation results obtained from the right-hand side and the expert (proportion agreement [Formula: see text], Cohen’s [Formula: see text]). This research created a new ergonomic method for the risk assessment of MSDs associated with sitting postures. The combination of theory and practice is crucial in the risk assessment of sitting postures in workplaces.

Accuracy Assessment of Joint Angles Estimated from 2D and 3D Camera Measurements.

To automatically evaluate the ergonomics of workers, 3D skeletons are needed. Most ergonomic assessment methods, like REBA, are based on the different 3D joint angles. Thanks to the huge amount of training data, 2D skeleton detectors have become very accurate. In this work, we test three methods to calculate 3D skeletons from 2D detections: using the depth from a single RealSense range camera, triangulating the joints using multiple cameras, and combining the triangulation of multiple camera pairs. We tested the methods using recordings of a person doing different assembly tasks. We compared the resulting joint angles to the ground truth of a VICON marker-based tracking system. The resulting RMS angle error for the triangulation methods is between 12° and 16°, showing that they are accurate enough to calculate a useful ergonomic score from.

Automatic real-time occupational posture evaluation and select corresponding ergonomic assessments

The objective is to develop a system to automatically select the corresponding assessment scales and calculate the score of the risk based on the joint angle information obtained from the imaged process (OpenPose) via image-based motion capture technology. Current occupational assessments, for example, REBA, RULA, and OWAS were used to evaluate the risk of musculoskeletal disorders. However, the assessment result would not be reported immediately. Introducing real-time occupational assessments in different working environments will be helpful for occupational injury prevention. In this study, the decision tree was developed to select the most appropriate assessment method according to the joint angles derived by OpenPose image process. Fifteen operation videos were tested and these videos can be classified into six types including maintenance, handling, assembly, cleaning, office work, and driving. The selected ergonomic assessment method by our developed decision tree in each condition are consistent with the recommendation of the Labour Research Institute. Moreover, the high-risk posture could be identified immediately and provide to the inspector for further evaluation on this posture rather than the whole operation period. This approach provides a quick inspection of the operation movements to prevent musculoskeletal injuries and enhances the application of the scale assessment method in different industrial environments.

A Preliminary Experimental Study on the Workers’ Workload Assessment to Design Industrial Products and Processes

The human-centered design (HCD) approach places humans at the center of design in order to improve both products and processes, and to give users an effective, efficient and satisfying interactive experience. In industrial design and engineering, HCD is very useful in helping to achieve the novel Industry 5.0 concept, based on improving workers’ wellbeing by providing prosperity beyond jobs and growth, while respecting the production limits of the planet as recently promoted by the European Commission. In this context, the paper proposes an ergonomic assessment method based on the analysis of the workers’ workload to support the design of industrial products and processes. This allows the simultaneous analysis of the physical and cognitive workload of operators while performing their tasks during their shift. The method uses a minimum set of non-invasive wearable devices to monitor human activity and physiological parameters, in addition to questionnaires for subjective self-assessment. The method has been preliminarily tested on a real industrial case in order to demonstrate how it can help companies to support the design of optimized products and processes promoting the workers’ wellbeing.

Why cumulative loading calculated using non-weighted integration may not be suitable for assessing physical stress of the lower back: an empirical investigation of strain during lifting and lowering tasks

When work-related physical stress is assessed using non-weighted integration, it is assumed that different loading conditions have a sufficiently comparable effect on the human body as long as the area under the loading curve is the same. Growing evidence cast doubt on whether this simple calculation can adequately estimate physical work-related strain. This study investigates in vivo, focussing on the lower back, whether the non-weighted method adequately reflects work-related physical strain of the lower back. Strain data resulting from lifting/lowering tasks performed in a laboratory study with an identical area under the loading curve but different load intensities were compared. Results showed that the non-weighted method does not sufficiently reflect the resulting muscular, cardiovascular and perceived strain but underestimates the influence of higher load intensity even in the range of medium physical exposure. Further research is needed regarding the determination of weighting factors and limit values. Practitioner Summary Given the dynamic nature of most physical work activities, the assessment of time-varying loading of the lower back is of particular interest in practice. Results show that the widely used non-weighted calculation method does not accurately reflect the resulting physical strain but underestimates the influence of higher load intensity. Abbreviations: MSD: musculoskeletal disorders; WMSD: work-related musculoskeletal disorders; KIM-LHC: Key Indicator Method Lifting, Holding, Carrying; RES: right erector spinae longissimus; LES: left erector spinae longissimus; HR: heart rate; RPE: rating of perceived exertion; EMG: surface electromyography; ECG: electrocardiography; SENIAM: Surface ElectroMyoGraphy for the Non-Invasive Assessment of Muscles; MVC: maximum voluntary contraction; ANOVA: analysis of variance; Std. error: standard error HIGHLIGHTS Results of this empirical investigation suggest that the widely used non-weighted calculation method is not fully suitable for calculating cumulative loading of the lower back. Even in the range of medium physical exposure the non-weighted calculation method does not accurately reflect the resulting strain on the human body but tends to underestimate the influence of higher load intensity due to higher external weight. Despite the same cumulative loading value obtained when using the non-weighted method, the resulting physical strain values are generally about 20–25% higher. The results may be used to further develop ergonomic assessment methods in order to avoid a misclassification of loading conditions and to prevent the risk of overexertion.

Analisis Faktor Risiko Nyeri Punggung Bawah Pada Perawat Di Rsud Dr. Murjani Sampit

Abstract: Low back pain (NPB) is one of the most common musculoskeletal disorders in everyday life. NPB is pain that is felt in the lower back and is usually local pain or radicular pain or both. This pain can be caused by poor posture when standing or sitting, bending / twisting, lifting weights incorrectly and so on. The cause of NPB often occurs in inpatient nurses. This case report is located in dr. Murjani Sampit, Kotawaringin Timur, Kaliantan Tengah. The purpose of this case report is to determine the risk factors for low back pain in nurses at dr. Murjani Sampit. The method used is a questionnaire to determine individual factors and the Brief Survey method for ergonomic risk assessment. A case study was conducted on 2 inpatient nurses who had a history of Lower Back Pain. Based on the results of the ergonomic risk assessment using the Brief Survey method, the highest work risk was in the back region with a score of 4. Characteristic factors of respondents including gender, BMI, work experience, smoking behavior and exercise habits did not have a significant relationship with the incidence of NPB. Based on the results of statistical tests obtained from several case studies and research shows that only the length of sitting and the length of standing that affect the incidence of low back pain

Study of association between OWAS, REBA and RULA with perceived exertion rating for establishing applicability

The paper highlights the need to determine applicability of various ergonomic assessment methods. The methods such as Ovako working posture analysing system (OWAS), Rapid entire body assessment (REBA) and Rapid upper limb assessment (RULA) were used for the evaluation. The current research is carried out in three phases. The first phase involves assessing 25 postures at four different load levels (100 postures) to confirm the existence of variation in outcome of assessment. In the second phase, 24 male participants were selected to simulate the selected set of 100 postures-load combination in the laboratory and their perceived exertion rating was noted. Phase three includes the result’s validation. ANOVA was carried out to identify significant factors. It may be concluded from the study that OWAS may be better suited to evaluate risk if the load is less than 5 kg. Similarly, REBA and RULA may be better suited for the load range 5 kg − 10 kg and load greater than 10 kg respectively. It is observed that outcome of assessment methods is insensitive to some posture cases. So, there is a need to identify all the insensitive zones within a method that has a considerable difference in perceived exertion.

Ergonomic postural assessment using a new open-source human pose estimation technology (OpenPose)

Observational ergonomic postural assessment methods have been commonly used to evaluate the risks of musculoskeletal disorders. Researchers have proposed semi-automatic methods using Kinect, known for limitations with body occlusions and non-frontal tracking. Meanwhile, new human pose estimation methods have been actively developed, and a popular open-source technology is OpenPose. This study aims to propose the OpenPose-based system for computing joint angles and RULA/REBA scores and validate against the reference motion capture system, and compare its performance to the Kinect-based system. Recordings of 10 participants performing 12 experimental tasks under different conditions: with/without body occlusions and tracked from frontal/non-frontal views were analyzed. OpenPose showed good performance under all task conditions, whereas Kinect performed significantly worse than OpenPose especially at cases with body occlusions or non-frontal tracking. The findings suggested that OpenPose could be a promising technology to measure joint angles and conduct semi-automatic ergonomic postural assessments in the real workspace where the conditions are often non-ideal.