User Expertise and Manual Materials Handling Risk Assessment: A Study of Chile’s 2018 Guide

PT PJC is a company synthetic resin. Synthetic resin is that produced by PT PJC is sold to the market in three types of packing, one of then is the drum packing type that weigh 208 kg. One of the activities that use the manual handling product (manual material handling) is the activity of filling, the drum-packed product will be transfered with drum packaging to the finishing goods area which done by the man force. Manual material handling concept has several advantages, one of which is easy to do by humans. However, manual handling material handling becomes an issue if the material load exceeds the maximum lifting of the worker because of the potential risk of injury to the human body, especially if it is carried out simultaneously for a relatively long period of time. One of the risks of human injury that can be experienced is Musculoskeletal Disorders (MSDs). This research will investigate the musculoskeletal complaints on Filling workers which will form the basic of the ergonomically-based Standard Operating Procedure (SOP) design basic. Data is taken by a Nordic Body Map (NBM) questionnaire. The result shows that most of the dominant body pain felt by the worker as the impact of previous day’s work was the complaints of pain on the left and right wrists, left and right palms, left and right knees, left and right calves, left and right ankles, while the pains felt by the workers after the activity are pain in the back, waist, left and right elbow, left and right thighs, left and right calvs, left and right ankles. The pain work will disappear after the night rest, but there is no guarantee that the worker’s body will be fit in the morning, because of the remnants of body pain that have not been fully fit, thus affecting the readiness of physical conditions at work in the morning. These body pain can be reduced by designing the right standard operating procedure (SOP) based on an ergonomic work attitude. Musculoskeletal pain before the activity were 39.3 ± 10.6 and after activity was 76.5 ± 14.9 or an increase in musculoskeletal pain of 94.66%.

ACC/AHA/AAP RECOMMENDATIONS FOR TRAINING IN PEDIATRIC CARDIOLOGY

This research is about the observation of workers transporting sacks in a traditional market. The worker complained about pain in many body parts like the shoulders, waist, and arms, which are presented in the results of the Nordic Body Map questionnaire. This problem can be solved by massaging the body section to reduce musculoskeletal disorders. Because it is often get massaged, it makes the completion time of sack transport become longer. Work posture must be improved because too much pain piles up over long periods and can impact condition health and decrease productivity. The purpose of this research is to evaluate the working posture while doing manual handling. Evaluate work posture using Rapid Entire Body Assessment (REBA) and Manual Handling Assessment Chart (MAC Tool). As a result, work posture and manual handling have a higher level of risk of injury, so we need to investigate and implement change. The level of risk must be reduced to at least medium risk. Using auxiliaries can improve work posture, reduce health risks, reduce load sacks, and increase work productivity. The recommended outcome is adding a skid box to improve the value of REBA and manual material handling by providing a hand trolley cart.

Introduction: Nowadays, most industries in Iran constitute a large proportion of workers' activities in Manual Material Handling. Musculoskeletal disorders are areas of erosive and inflammatory conditions that occur in the form of pain and discomfort in the muscles, tendons, ligaments, joints, peripheral nerves, blood vessels. Working hours, absenteeism, increasing work restrictions, job changes and disability and impose many economic consequences on the individual, organization, and society. Materials and Methods: The present study was conducted to review the studies of Manual Material Handling by different methods in Iran from 2010 to 2020. The general process of the present study included searching for articles invalid national and international databases. After selecting the articles, the necessary information was extracted and analyzed. In general, based on the inclusion criteria, only studies that used NIOSH, KIM, SNOOK, 3DSSPP, WISHA, UTAH, MAC, ART, and manual handling regulations in Iran, were reviewed. Results: 15 English articles and 50 Persian articles were found, of which 44 articles were deleted based on the exclusion criteria, and 21 articles were selected for this study and entered into the final analysis. Conclusion: The highest number of studies was conducted in Hamedan, Tehran, Mallard, Shiraz, and Qazvin, respectively NIOSH, KIM and 3DSSPP were the three methods used with the highest number of studies in the field of Manual Material Handling in industry. Most workplace studies were conducted in the casting, food industry, tile industry, and hospital.

Ergonomic evaluation of workers during manual material handling

BACKGROUND:Even in an era of automation and digitalization, Manual Material Handling (MMH) can be called the most common industrial task. The aim of this study was to evaluate the prevalence of musculoskeletal disorders (MSDs) induced by manual handling tasks on the workers of a printing factory in Tehran in 2017 and then to evaluate the effectiveness of a training intervention based on health promotion.MATERIALS AND METHODS:This study had quasi experimental design and was conducted on 40 men. First, demographic data were collected and the Nordic questionnaire was used to determine the prevalence of MSDs in workers. Then, MMH tasks were assessed using Manual Handling Assessment Chart (MAC). A short training course was designed to promote health. Finally, the same MMH tasks were re-evaluated 3 months after the training intervention.RESULTS:Among the various tasks, the highest prevalence of work-related MSDs (WMSDs) was observed in the lower back (77.5%) and shoulder (62.5%). Based on the final scores of the MAC method, the jobs that received the highest scores were cutting (individual lifting), with 22 scores and action level “immediately necessary,” cutting (individual load carrying), with 15 scores with action level “urgently needed.” Arranging the forms (individual lifting) received a similar score. After the training intervention, the estimated risk level reduced by 12, 9, and 6 points, respectively, reaching a safe action level, i.e., “necessary in the future.”CONCLUSION:The results demonstrated that educational interventions might be equally effective in low-technology work environments. More in general, the MAC method can be used to make informed planning of educational interventions against WMSDs risk in MSDs. This health promotion approach is critical for care of human recourse.

This paper investigates interactions between user expertise and formats of instructional presentations. A cognitive load approach assumes that information presentation should be structured to eliminate any avoidable load on working memory. The level of learner expertise is a major factor determining intelligibility of information for a user. A diagram might not be intelligible in isolation for less experienced users and so require additional textual explanations. Physical integration (e.g., using spatial grouping or colour coding) of the text and diagram can reduce split attention and an unnecessary working memory load. The same diagram may be understandable for more experienced users. Eliminating redundancy may be the best way to reduce cognitive load in this situation. A series of experiments using instructions in elementary electrical engineering demonstrated the alterations in optimal instructional designs with the development of user expertise.

According to a recent research, manual working with high levels of static contraction, repetitive loads, or extreme working postures involving the neck and shoulder muscles causes an increased risk of neck and shoulder musculoskeletal disorders. We investigated the effects of the forwardly worktable position on head and shoulder angles and shoulder muscle activity in manual material handling tasks. The forward head and shoulder angles and the activity of upper trapezius, levator scapulae, and middle deltoid muscle activities of 15 workers were measured during performing of manual material handling in two tasks that required different forward head and shoulder angles. The second manual material task required a significantly increased forward head and shoulder angle. The upper trapezius and levator scapulae muscle activity in second manual material task was increased significantly compared with first manual material task. The middle deltoid muscle activity in second manual material task was not significantly different compared with first manual material task. Based on this result, the forward head and shoulder angles while performing manual work need to be considered in selection of the forward distance of a worktable form the body. The high level contractions of the neck and shoulder muscles correlated with neck and shoulder pain. Therefore, the forward distance of a worktable can be an important factor in preventing neck and shoulder pain in manual material handling workers.

Ergonomic risk assessment tools are tools that have been designed to solve the problem of ergonomics in the workplace from manual material handling activities. The objective of this study is to investigate Musculoskeletal Discomfort among workers related to manual handling activities using Cornell Musculoskeletal Discomfort Questionnaires (CMDQ); to assess an ergonomics risk factor among workers related to manual handling activities using Manual Handling Assessment Chart (MAC), NIOSH Lifting Equation(NLE), and Key Indicator Method for Manual Handling Operation (KIM-MHO) method and; to compare the results between CMDQ and assessment tools. This case study was conducted in Parit Raja, Johor, Malaysia involving 34 male mechanics workers. The tools used are as stated in the objective with the help of measurement tools such as a goniometer. The result of the CMDQ reveals that the body part with the highest discomfort level among the workers in the lower back, shoulder right and shoulder left with the percentage from the total discomfort score of 20.91%, 13.57%, and 13.36% respectively. From the result of the assessments, it is concluded that the highest risk factor contributing to the MSDs is the bad posture of the worker during the manual handling operation followed by the frequency of lifting and the weight of the load. By comparing assessment tools, the first comparison is made between the CMDQ versus KIM-MHO, MAC Tools and NLE. In this comparison that, it is highlighted the result type from CMDQ are different from the KIM-MHO, MAC Tools and NLE as its questionnaire result shows us the discomforts levels on the body of workers and the body parts affected on their body for the last seven days but the assessment tools results show us the risk factor that contributes to the MSDs. For the comparison between the three assessment tools, it can be said that the tools that have the highest correlation with CMDQ are MAC Tools. In conclusion, most workers suffer from MSDs in their lower back due to their bad posture during manual handling. KIM-MHO is the best assessment tool among the three as it has the highest significance value while being the easiest tool to be used.

The most frequent and expensive cause category of compensable loss is manual material handling (MMH). Casting workers who handle oxygen (O 2) cylinders manually are at risk for work-related musculoskeletal disorders (WMSDs). The aim of this study was to assess manual handling of O 2 cylinders by casting workers and to implement ergonomic intervention to reduce the risk of musculoskeletal disorders (MSDs). This interventional study was conducted on 30 male workers of casting unit in a steel industry. Nordic Musculoskeletal Questionnaire was used to determine the prevalence of MSDs in workers. Snook tables and its software were used to assess manual handling risk of O 2 cylinders. Manual handling of O 2 cylinders was totally excluded using the box with 16 cylinders that can be moved by crane. The most common MSDs in 1 year prior to the study were low back pain (43%), shoulders (33%), and hand/wrist and knee disorders (16%), respectively. The Snook tables’ results indicated that 86% of lifting/lowering, 100% of carrying, and 50% of pulling tasks were appropriate for <10% of casting workers. About 94% of O 2 cylinders pushing were appropriate for 17% casting workers. With the implementation of ergonomic intervention, the risk of WMSDs and explosion of cylinders was decreased, and safety of workers was improved.

OCCUPATIONAL APPLICATIONS In this study, a biomechanical exposure assessment methodology for combined manual material handling tasks is devised using the “cube” model approach (including time, force, and posture), specifically by modifying the model dimensions. The resulting modified cube model aims to facilitate biomechanical exposure assessment of manual material handling tasks, particularly for industrial conditions where a chain of combined manual material handling activities is carried out across a wide geographical area, and where no direct measurements of biomechanical exposures are available. This methodology can help in prioritizing high-exertion manual material handling tasks for subsequent ergonomic analysis and redesign.TECHNICAL ABSTRACT Background: Biomechanical exposure measurement is difficult for combined manual material handling tasks in field settings and/or resource-constrained environments. “Cube” models—integrating time, force, and posture—have been used previously, but existing models have not been applied to manual material handling tasks. Purpose: The objective of this study was to develop a revised cube model as a biomechanical exposure assessment tool for combined manual material handling tasks. Methods: The study was conducted in a bearing manufacturing plant in India. First, a work-sampling approach was used to observe all manual material handling tasks and record relevant details. Then, two modified models—cube model 1 and cube model 2—were developed by modifying the existing cube model dimensions; physical load intensity and overall physical load were calculated using these two models under a novel cumulative exposure measurement framework. Decision criteria for cumulative cube score were formulated to classify manual material handling tasks under three physical load levels (i.e., low, medium, and high). Finally, cube model assessments were compared with biomechanical assessments of all manual material handling tasks. Results: Attribute agreement (overall correct classification) values for the existing cube model, cube model 1, and cube model 2 were 39%, 61%, and 69%, respectively, indicating better performance for cube model 2. Spearman rank order correlations comparing cumulative cube scores with cumulative biomechanical measures ranged from 0.73 to 0.94, which is considered to be high. Conclusions: The study presents a methodology to assess biomechanical exposures for combined manual material handling tasks by modifying the existing cube model. A cumulative dose concept as applied in biomechanical analysis was used in the study. The cumulative cube score is proposed as a proxy to indicate the overall biomechanical exposure during a combined manual material handling task. Cumulative cube scores gave good agreement between cube model 2 evaluations and biomechanical evaluations, supporting its applicability for evaluating manual material handling tasks.

Manual material handling is an activity that provides easy load transfer in confined or irregular spaces. Based on the Global Burden of Disease (GBD) shows that around 1.71% billion people worldwide have musculoskeletal conditions. This study aims to analyze articles from journals in order to provide reliable information about the effect of manual material handling activities on workers' complaints of musculoskeletal disorders. This study uses a systematic review method by comparing the search results to the literature that has been obtained regarding manual material handling of workers for musculoskeletal complaints. The results obtained were 20 articles which were analyzed in a systematic review. Article published in Elsevier B.V, PubMed, Google Scholar. The inclusion criteria used were having full text, using English and Indonesian, having ISSN/ISBN, and being published in the last 7 years. While the exclusion criteria referred to are research articles that do not meet the sample, are irrelevant, do not comply with the provisions as a predetermined sample, the period of publication of the article before 2014, does not have the complete text, and does not have an ISSN or ISBN. All articles cover manual material handling activities that affect workers' musculoskeletal complaints. Manual material handling consists of pushing, pulling, lowering, lifting, and carrying objects. It can be concluded that proper manual material handling can improve the quality of life for workers.

The objective of this study was to evaluate the work strategies of obese and healthy-weight workers in manual materials handling. Seventeen obese and 20 healthy-weight manual materials handlers participated in this laboratory study. The tasks consisted of transferring four boxes between a hand trolley and a conveyor. The weight of the box (15 vs. 23 kg), the handling height and the working configuration were modified to see what impact these changes had on the participants’ manual materials handling. Biomechanical measures included net moments, expressed in the pelvic system (flexion–extension, lateral bending and torsion moments), kinematics of body segments and box displacements. The results indicated that trunk and knee postures and horizontal hand distances from L5/S1 were not significantly different between the two groups. Peak moments of force around the transverse, sagittal and longitudinal axes at L5/S1 were 13.3% to 59.0% higher during box lifting and lowering for the obese than for the non-obese workers. The individuals’ body weight explained 57% of the variability in the maximal transverse moments of force at L5/S1 during the lifting of the boxes from the ground. These results suggest that the extra mass of an obese worker causes additional stress for the musculoskeletal structures of the back. These biomechanical differences potentially place obese workers at a greater risk of developing musculoskeletal problems during manual materials handling.

Efficacy of classical manual material handling (MMH) training interventions on back pain prevention at the workplace has been called into question. The way that observation (self-observation or hetero-observation) is used in other areas to create feedback addressed to modify motor activities can justify innovative components for these interventions. However, their implementation and evaluation cannot be done without tackling the methodological challenge of developing a reliable observational instrument to measure manual handling practice during the training process. The aims of this study were: (1) justify and develop an hetero-observation (H-O) instrument to assess changes in the worker behavioral patterns with a level of analysis convenient to derive a parallel version for the systematic self-observation (S-O) during training on MMH; (2) provide evidence on the inter-rater reliability of the H-O instrument; (3) provide evidence on the usability of the S-O instrument and its perceived usefulness; and (4) provide evidence on the benefits that can be derived with the use of the H-O instrument to create feedback based on T-pattern and polar coordinate analysis. A mixed method approach mainly grounded on systematic observation was used. A convenience sample composed by blue-collar workers participated in the study. Based on literature review and expert opinion, the H-O instrument proposed was composed by six dimensions (feet, knee joints, back, elbow joints, load position, and interaction between back tilt and displacement) plus a structural dimension which defined MMH phases. The inter-rater reliability of this instrument was almost perfect for all dimensions using a tolerance level of 2 s (the range of time-unit kappa was from 0.93 to 0.97 and the range of event-based kappa was from 0.82 to 0.9). The usability and usefulness of the S-O instrument was highly valued by workers. Regarding the way to use hetero-observations to create feedback, the paper shows the great potential of T-pattern and polar coordinate analysis. The observational instruments developed combined with these techniques make it possible to characterize the body positions adopted during manual handling performance, and this is crucial to create feedback on performance instead of only feedback on results.

Manual material handling (MMH) exposure arises from the work system characteristics leading to strain on musculoskeletal, cardiovascular and neurological system. A combined manual material handling task is composed of a combination of tasks involving lifting, lowering, pushing, pulling or carrying. The paper highlights interventions for a MMH work system in a bearing manufacturing plant in India through an experimental study where workers are faced with both biomechanical and physiological strains while undertaking combined MMH tasks. The intervention procedure proposed for combined manual material handling tasks in this study accounts for both biomechanical and physiological strains. The biomechanical measures considered for interventions are ‘Body Part Discomfort Frequency Severity’ and ‘Muscle effort’, and physiological measures considered for interventions are ‘energy expenditure rate’, ‘heart rate’ and ‘rating of perceived exertion’. The design solutions have addressed the whole-body exertions faced by the material handlers. The practical implication of the study is that it has highlighted a few work system characteristic that produces less biomechanical and physiological stresses. Several recommendations for improved work system factors (e.g. load, equipment, and workplace) for combined loading, push–pull and unloading tasks are provided. The recommended interventions are generic and can be used in any MMH work system where human effort is dominant, and level of mechanization is low. The values obtained from this simulation are only first approximation and need to be verified through actual implementation of the interventions.