Correlations in between EAWS and OCRA Index concerning the repetitive loads of the upper limbs in automobile manufacturing industries

Upper limbs repetitive tasks are one of the main sources of risk for the workers of the manufacturing industries and the standards ISO 11228-3 and EN 1005-5 addressed this issue since 2007. EAWS (European Assembly Worksheet) is a 1st level ergonomic risk assessment method and it provides in its 4th section a score to measure the load level for the upper limbs based on a traffic light scheme. According to the relevant ISO/CEN standards, the OCRA Index is the preferred system to refer to in the evaluation of the biomechanical stress of hand-harm-shoulder system. This correlation study is based on a 45 workstations sample coming from the automobile manufacturing industry. According to the results, EAWS4 shows an excellent correlation with OCRA index (Spearman's rho correlation index 0.95). Being EAWS based on biometric statistical data distribution, its typical application is the process design phase, but adopting a conservative approach in the interpretation of EAWS4 score for risk mapping purposes, it provides an equivalent "reaction" pattern (countermeasures to be taken in the production phase) with respect of OCRA Index with an Odds Ratio ranging from 0.89 (OR-matched) to 1.00 (OR-conservative).     

Association between repetitive work and occupational cold exposure

Occupational cold exposure is an important risk factor that increases stress at work and can induce many health effects like diseases and symptoms related to cold, including work-related musculoskeletal disorders. The methodological procedures were performed to measure these environmental variables as recommended by the ISO 7726/85. For the analysis of repetitiveness was used the OCRA checklist and evaluation of musculoskeletal morbidity conducted by the Nordic Musculoskeletal Questionnaire. So the objective of this study was to investigate the correlation between cold environmental variables and prevalence of musculoskeletal morbidity in the repetitive work. Was found association between work in cutting and boning sector (occupational cold and repetitive work) and the presence of musculoskeletal morbidity, with a significance of 99%.     

Ergonomic evaluation in a values transportation company in Venezuela

The objective was to analyze the work activity and identify risk factors that could account for musculoskeletal disorders in the upper extremities, shoulder and neck of workers of a transport values company in Venezuela. The methods used were: collective interview, tasks observation, evaluation of posture with RULA method and evaluation of repetitive motions with the OCRA method. Five workstations were evaluated. Main problem perceived by workers was: exposure to chemical and biological hazards when handling paper money and coins; inadequate chairs and close supervision. The postures level risk was 1 or 2 for the RULA scale. Only two workstations showed ligth and medium risk level by OCRA method. Conclusion: The factors identified that could explain the musculoskeletal changes were: wrist repetitive flexion and extension, shoulder elevation, lifting weight above shoulder height, elbow repetitive flexion and extension, neck flexion, extended work journey, work overload, high responsibility and strict supervision by a video camera.     

Relationship between productivity, quality and musculoskeletal disorder risk among deboning workers in a Chilean salmon industry

The purpose of this ergonomic investigation is to establish a relationship between quality, productivity and risk of musculoskeletal disorder (MSD) in manual bone-removal process in the salmon fish industry. The method consists in a follow up study of 14 workers in a lane that processes salmon steak. Time between each steak (work cycle), quality of the steak's meat through inspection of deepness and length of the gapping generated by the manual bone-removal process and risk for musculoskeletal disorders through OCRA method were considered for this study. IMC and musculoskeletal Nordic Questionnaire of Kourinka were applied to the workers evaluated. Fourteen women worker's completed the evaluation, age 37.67 ± 8.1, with 65.27 ± 34.41 months of experience, with an IMC of 27.18 ± 3.87 (1.52 ± 0.057 meters of height) at the time of the evaluation. Time for deboning per steak averaged 38 ± 14 seconds with 68.33 ± 14.79 steaks per hour per worker. In quality terms, 74% of the steaks were qualified as "premium steaks" and 26% as "grade or industrial" (lower category and cheapest price). OCRA index for the right hand average 13.79 ± 4.59 and 3.59 ± 0.41 for the left hand. From Nordic questionnaire 80% of the workers manifested musculoskeletal symptoms in the right hand/wrist, followed up by shoulder with 60% of the workers and arm/elbow with over 50%. There was no statistically significant relationship between productivity and quality of the steak after manual bone removal process and between quality and MSD risk. However, there was a statistically significant relationship between productivity and MSD risk (p<0.05). Discussion around the results allows to see complementary results that did have strong correlation between MSD risk and the presence of lower grade salmon steaks and between areas that present musculoskeletal symptoms (MSS) and the intensity of the MSS (p<0.05). The results showed that further research is needed to validate these relationships, due to the increasing demands of health-care services from this productive sector, considering its importance for this region.     

Occupational stress and biomechanical risk in a high fashion clothing company

Psychosocial discomfort may amplify job-related risk factors. The aim of this study is to evaluate job stress in a high fashion clothing company with upper limb biomechanical overload due to repetitive and forceful manual activities. Biomechanical risk was analyzed and in part reduced using the OCRA Check list. A total of 518 workers (433 females and 85 males) were investigated to determine anxiety (by STAI 1 and 2), occupational stress (using the Italian version of the Karasek Job Content Questionnaire) and perception of symptoms. Final biomechanical assessment did not reveal high risk jobs, except for cutting. Although the perception of anxiety and job insecurity was within the normal range, all the workers showed a high level of job strain (correlated with the perception of symptoms) due, probably, to very low decision latitude. It was suggested that job strain may increase the perception of symptoms. Moreover, the result of this study indicates that musculoskeletal overload has to be further analyzed since its low level is not in agreement with the level of discomfort due to the repetitive tasks.     

An equation to predict maximum acceptable loads for repetitive tasks based on duty cycle: evaluation with lifting and lowering tasks

Recently, an equation was developed to predict maximal acceptable effort (MAE) for repetitive tasks based on the product of task frequency and effort duration (ie. duty cycle). This equation has been shown to closely match data from psychophysical studies of the upper extremities. In the current paper, the applicability of this equation was tested on lifting and lowering data from Snook and Ciriello (1991) and was found to fit closely, even at very low duty cycles.     

Analyzing Web pages visual scanpaths: between and within tasks variability

In this paper, we propose a new method for comparing scanpaths in a bottom-up approach, and a test of the scanpath theory. To do so, we conducted a laboratory experiment in which 113 participants were invited to accomplish a set of tasks on two different websites. For each site, they had to perform two tasks that had to be repeated ounce. The data were analyzed using a procedure similar to the one used by Duchowski et al. [8]. The first step was to automatically identify, then label, AOIs with the mean-shift clustering procedure [19]. Then, scanpaths were compared two by two with a modified version of the string-edit method, which take into account the order of AOIs visualizations [2]. Our results show that scanpaths variability between tasks but within participants seems to be lower than the variability within task for a given participant. In other words participants seem to be more coherent when they perform different tasks, than when they repeat the same tasks. In addition, participants view more of the same AOI when they perform a different task on the same Web page than when they repeated the same task. These results are quite different from what predicts the scanpath theory.     

Integration of Thought and Action: Arm Weights Facilitate Search Accuracy in 24‐Month‐Old Children

Search errors are common in cognitive tasks with infants and toddlers, and these errors reveal important insights to the development of competence and performance. Rivière and Lécuyer (2008, Journal of Experimental Child Psychology, 100, 1) demonstrated that 29‐month‐olds typically make an error during a search task involving invisible displacement. However, performance improves significantly when children wear weighted wrist bands while doing the task. To investigate this phenomenon further, we tested 24‐month‐old children in an identical search task (N = 35). Half the children wore weighted wrist bands, and the rest were in a no‐weight condition. To test how far this phenomenon generalizes, we also tested the same children in a second search task where they needed to find a ball that had rolled behind one of four doors. The results showed that children in the no‐weight condition replicated previous findings of poor performance on both search tasks. Unlike 29‐month‐olds, the 24‐month‐olds in the weighted condition did not immediately show improvement on the search tasks. However, after an initial search attempt, children wearing weights performed significantly better than chance. The findings shed new light on the interplay between thought and action.     

《TRIZ理论与创新方法》课程项目化教学研究

案例教学法与项目化教学法相辅相成,设计了创新课程《TRIZ理论与创新方法》的教学过程。将精细日用化学品的概念设计作为训练项目,分解为一系列任务,以期在任务完成过程中实现学生创新能力的培养与提高。     

Application of the OCRA Method in the sugar cane harvest and its repercussion on the workers' health. Preliminary study

In Brazil the sugar ethanol industry has had strong growth in the last 10 years, sometimes due to the growing sugar exportation, sometimes due to the alcohol production for automobile fuel and for exportation. Despite the growing mechanization of the raw material harvest (sugar cane), the manual work still persists. The development of this article was based in the application of the OCRA Method in the sugar cane harvesting process, to evaluate the risks to the upper limbs by repetitive movements and epidemiologically prove the ratio risk x harm to the heath of the workers, as well as the probability of developing improvements in the working conditions. The analysis process consists of studying the work organization, the risks to the health of the worker and the distribution of the recovery periods during the working day.     

Assigning volunteer tasks: The relation between task preferences and functional motives of youth volunteers

In this paper we aim to explore the relationship between volunteer motives and task preferences in order to provide volunteer managers with better insight in how tasks can be assigned to keep youth volunteers satisfied. Earlier seminal contributions have either taken a pure functional approach – where various types of motives are supposed to be at the base of any type of volunteer work – or a differentiated approach, where particular motives relate to specific task preferences. However, empirical results reported in the literature do not justify the preference of one approach above the other. To investigate whether one of the approaches is superior, or whether a combination of both is more appropriate, we perform a canonical correlation analysis for a set of functional motives and a set of task preferences (N = 2158). Five distinct relationships (canonical variate pairs) of motives and preferences are found. Results show that a ‘functional basis’ exists where all motives relate to a basic set of tasks. Additionally, a more differentiated approach towards volunteer motives and task preferences has to be taken, as we find four other relationships where specific motives are satisfied by assigning particular sets of tasks.     

Level of self-reported neck/shoulder pain and biomechanical workload in cleaners

The aim of the present study was to investigate the relation between self-reported pain, muscular activity and postural load during cleaning tasks. Eighteen cleaners performed usual cleaning tasks in both a laboratory and a lecture room. The level of perceived pain in the neck-shoulder region during the last 7 days was recorded. Bipolar surface electromyography (SEMG) was recorded bilaterally from upper trapezius and erector spinae muscles during cleaning. Root mean square (RMS) and permutation entropy (PE) values representing amplitude and complexity of SEMG time-series were estimated. A tri-axial accelerometer package was mounted on the low back (L5-S1) to measure postural changes during cleaning tasks. The 10th, 50th and 90th percentiles of the angular distributions were computed to characterize postures and movements. Pain tended to play a significant role on RMS of left/right trapezius and left erector spinae muscles (P≤0.08). Cleaners with low pain level exhibited higher muscular activity during cleaning. Pain played or tended to play a significant role on PE of left and right erector spinae muscles (P≤0.08). Pain played a significant role on the 10th, 50th and 90th percentile (P<0.05) of lateral flexion angle (side bending). The present study emphasizes biomechanical adaptations occurring in presence of neck-shoulder pain during cleaning tasks.     

A longitudinal study of the learning and retention of task-specific training

This longitudinal study evaluated the learning and retention of task-specific training during the subjects' classroom performance of a one-person pivot transfer. Twelve subjects were videotaped completing the transfer (pretest). The subjects then participated in a two-hour training session. One week later (posttest 1), and one year later (posttest 2) the subjects were videotaped again. A checklist was used to analyze the videotapes. A one-way ANOVA with repeated measures revealed that there was a statistically significant difference between the tests (F = 243.73, p-value < 0.0001). A post hoc analysis (Bonferroni procedure) indicated that the posttest 1 scores (mean = 13, SD = 0.40) were significantly higher than the pretest scores (mean = 2.96, SD = 0.39) indicating an improved score on the checklist. There was no significant difference between the scores of posttest 1 and posttest 2 (mean = 12.79, SD = 0.60) indicating that subjects continued to perform the task with proper body mechanics one year post training.     

Ergonomic assessment methodologies in manual handling of loads--opportunities in organizations

The present study was developed based on the analysis of workplaces in the engineering industry, particularly in automotive companies. The main objectives of the study were to evaluate the activities present in the workplace concerning manual handling, using assessment methodologies NIOSH Ergonomic Equation [1] and Manual Material Handling [2], present in ISO 11228 [3-4], and to consider the possibility of developing musculoskeletal injuries associated with these activities, an issue of great concern in all industrial sectors. Similarly, it was also shown the suitability of each method to the task concerned. The study was conducted in three steps. The first step was to collect images and information about the target tasks. As a second step proceeded to the analysis, determining the method to use and to evaluate activities. Finally, we found the results obtained and acted on accordingly. With the study observed situations considered urgent action, according to the methodologies used, and proceeded to develop solutions in order to solve the problems identified, eliminating and / or minimizing embarrassing situations and harmful to employees.     

Biomechanical strain of goldsmiths

The work of the goldsmiths consists in the manufacture of jewelry. The piece, be it an earring, bracelet or necklace, is hand-assembled. This task requires precision, skill, kindness and patience. In this work, we make use of tools such as cuticle clippers and rounded tip, beads or precious stones and also pieces of metal. This type of activity requires a biomechanical stress of hands and wrists. In order to quantify the biomechanical stress, we performed a case study to measure the movements performed by an assembly of pieces of jewelry. As method for research, filming was done during assembly of parts to a paste, using a Nikon digital camera, for 1 (one) hour. The film was edited by Kinovea software, and the task was divided into cycles, each cycle corresponds to a complete object. In one cycle, there are four two movements of supination and pronation movements of the forearm. The cycle lasts approximately sixteen seconds, totaling 1800 cycles in eight hours. Despite the effort required of the wrists, the activity shows no complaints from the employees, but this fact does not mischaracterizes the ability of employees to acquire repetitive strain injuries and work-related musculoskeletal disorders.     

The task dilemma in human service organizations and its impact on efficacy A possible solution developed out of the theory of society of ürgen Habermas

In modern societies the professional social worker within human service organizations suffers from a phenomenon which can be called a task dilemma. According to this model, social service agencies are confronted daily with two ideal types of basic tasks: social integration and system integration. It is the paradox of these agencies that they are asked to fulfil both basic tasks, although the accomplishment of one works against the accomplishment of the other. The problem which will be discussed in this article is that both tasks must be accomplished, but each requires a different structure. Consequently, the task dilemma provokes a structure dilemma which necessarily diminishes work quality in this type of organization. The task dilemma will be explained according to specific elements of the theory of society derived from Habermas (1987a, 1987b). Using this approach, a new conceptual design will be derived which allows social work organizations to consciously and constantly determine their basic task priority. This concept is called the programme of structuration. It implies, as in a learning organization, a continuous evaluation of the specific organizational norm and basic task as well as the adaptation of the corresponding organizational structure. The implementation of this programme promises the guarantee of high efficacy in social service agencies in the long run.     

Hazard identification and pre-map with a simple specific tool: synthesis of application experience in handicrafts in various productive sectors

In August 2009, an international group was founded with the task of developing a "toolkit for MSD prevention" under the IEA and in collaboration with the World Health Organization.According to the ISO standard 11228 series and the new Draft ISO TR 12259 "Application document guides for the potential user", our group developed a preliminary "mapping" methodology of occupational hazards in the craft industry, supported by software (Excel?, free download on: www.epmresearch.org).The possible users of toolkits are: members of health and safety committees; health and safety representatives; line supervisors; foremen; workers; government representatives; health workers providing basic occupational health services; occupational health and safety specialists.The proposed methodology, using specific key enters and quick assessment criteria, allows a simple ergonomics hazards identification and risk estimation to be made. It is thus possible to decide for which occupational hazards a more exhaustive risk assessment will be necessary and which occupational consultant should be involved (occupational physician, safety engineer, industrial hygienist, etc.).The methodology has been applied in different situations of small and medium craftsmanship Italian enterprises: leather goods, food, technical dental work, production of artistic ceramics and stained glass, beekeeping activities. The results are synthetically reported and discussed in this paper.     

The evaluation ranking scale: clarification of methodological and procedural issues

Compared with CSQ-8, a typical questionnaire approach to assessing global patient satisfaction, the Evaluation Ranking Scale (ERS) had equally good patient acceptability, yielded more normally distributed satisfaction scores, and results allowed comparative information about patients' evaluation of specific service dimensions. The study also addressed key questions that have emerged about the ERS procedure. Patients apparently do not distinguish conceptually between "importance" of dimensions and "satisfaction" with dimensions in the first phase (ranking) of the ERS. Results did confirm that the ERS sequence of ranking and then rating the dimensions is essential to achieving optimal utility of results. The ranking task seems to have an organizing effect on patients' approach to the rating task. This effect does not work to dictate results in the rating phase but rather seems to familiarize patients with the dimensions to be rated thereby yielding greater potential discriminative capacity for the ERS. Finally, results indicate that the ERS can be administered in a flexible fashion that yields additional information about the absolute importance of the six dimensions without loss of desired operating characteristics for the measure.