Ergonomic evaluation of conventional and improved methods of aonla pricking with women workers

Conventional and improved methods of aonla pricking were evaluated ergonomically on an experiment conducted for 20 minute with women workers. The working heart rate, energy expenditure rate, total cardiac cost of work and physiological cost of work with conventional tools varied from 93-102 beats.min-1, 6-7.5 kJ.min-1, 285-470 beats, 14 -23 beats.min-1 while with machine varied from 96-105 beats.min-1, 6.5-8 kJ.min-1 , 336-540 beats, 16-27 beats.min-1 respectively. OWAS score for conventional method was 2 indicating corrective measures in near future while with machine was 1 indicating no corrective measures. Result of Nordic Musculoskeletal Questionnaire revealed that subjects complaint of pain in back, neck, right shoulder and right hand due to unnatural body posture and repetitive movement with hand tool. Moreover pricking was carried out in improper lighting conditions (200-300 lux) resulting into finger injuries from sharp edges of hand tool, whereas with machine no such problems were observed. Output with machine increased thrice than hand pricking in a given time. Machine was found useful in terms of saving time, increased productivity, enhanced safety and comfort as involved improved posture, was easy to handle and operate, thus increasing efficiency of the worker leading to better quality of life.     

Comparison of ergonomic risk assessment outputs from Rapid Upper Limb Assessment and the Strain Index for tasks in automotive assembly plants

This paper compares the ergonomic risk assessment of a task for the upper extremities as determined by Rapid Upper Extremity Assessment (RULA) and the Strain Index (SI). The ergonomic risk to the upper extremities of 244 automotive assembly plant tasks were evaluated using RULA and SI. The outcomes of each tool were compared for each task. Results from this study provide practical insight into the methods used in each tool. This study compared only the ergonomic risk outputs from each tool; it does not pursue the question of which tool best predicts injury. The kappa score was 0.11, indicating little agreement between the outputs of the two tools. This is supported by the lack of monotonicity with a gamma score of 0.1. These results indicate that the risk assessment outcome of these two ergonomic assessment tools for the upper extremities do not agree.     

Workers' postural conditions in the charcoal production proccess based on vertical metallic cylynders

Considering the importance of posture to the workers' health in the production of charcoal, this paper presents an ergonomic research based on a biomechanical focus that aims to evaluate the posture adopted by these workers on the production of charcoal in vertical metallic cylinders. Thus, it was verified the incidence of pain and/or musculoskeletal injuries to these workers. Also, it was evaluated the weight carried by them and the positions taken in their daily tasks. Applying the Ergonomic Analysis of Labor, the data collection was done by directly observing the workers, registering images, by interviews, and posture analysis based on the OWAS method. The main results of the research show that there are postures with risks in the four levels of musculoskeletal injuries classified by OWAS, concluding that the method is imperative for ergonomic recommendations for minimization or eradication of suffering injury and worker's postural constraints.     

Ergonomic evaluation of postural stress in school workshop

The objective of this study is to compare the evaluation of postural analysis between a self-report questionnaire and physical assessments methods for students aged 13 to 15 years old in school workshop. 336 students were volunteered as participants to fill in the questionnaire and being observed in the workshop. Total of 104 positions were selected and analyzed while students performing their tasks. Questionnaire data was examined to specify the prevalence of postural stress symptoms. The relationship of postural stress by physical assessment methods (RULA and REBA methods) was defined to identify the risk level of students' working posture. From the results, comparison of four factors categorized from total of 22 questions among ages, the mean values were lower for 13 years old students meaning that they were faced higher posture problems while using the workstation. The obtained results from both physical assessment methods and questionnaire analysis have identified 13 years old students faced higher risk exposure. Analysis results emphasized the fact that self-reports questionnaire method has almost accurate as postural evaluation methods to identify physical risks in workplace. The result also shows that an intervention is needed to overcome the posture problems.     

Ergonomic evaluation of the preparation of cuttings and minicuttings for eucalyptus seedling production, with the use of scissors

This study was conducted in a nursery for eucalyptus seedling production in a forest Company, located in the southern state of Bahia, Brazil. It aimed to evaluate the ergonomic conditions of the preparation of cuttings and mini-cuttings with scissors for Eucalyptus seedling production to increase well-being, satisfaction and safety and minimizing the occurrence of occupational diseases, also improving the process efficiency and final product quality. Environmental conditions, levels of noise, postures, RSI risk and physical workload were assessed. The environmental conditions complied with the recommended norms, except at certain times of day, when workers should make compensation breaks. The workers that collect minicuttings presented postures classified as normal by OWAS. On the other hand, the posture of workers dealing with cutting preparation requires corrections in a short run. The workers were subjected to moderate RSI risk due to the high degree of repeatability found. The physical workload was classified as mild, with no need for ergonomic interventions.     

Ergonomic evaluation of a wheelchair transportation securement system

The Americans with Disabilities Act (ADA) specifies guidelines covering the securement system and environment for wheeled mobility device (WhMD) passengers on the public bus system in the United States, referred to as the wheelchair tiedown and occupant restraint system (WTORS). The misuse or disuse of the WTORS system can be a source of injury for WhMD passengers riding the buses. The purpose of this study was to quantify the risks posed to the bus driver while performing the WTORS procedure using traditional ergonomic analysis methods. Four bus drivers completed the WTORS procedure for a representative passenger seated in three different WhMDs: manual wheelchair (MWC), scooter (SCTR), and power wheelchair (PWC). Potential work-related risks were identified using the four most applicable ergonomic assessment tools: PLIBEL, RULA, REBA, and iLMM. Task evaluation results revealed high levels of risk to be present to drivers during the WTORS procedure. The securement station space design and equipment layout were identified as contributing factors forcing drivers to adopt awkward postures while performing the WTORS task. These risk factors are known contributors to injury and the drivers could opt to improperly secure the passengers to avoid that risk.     

Intervention of gender friendly land preparation technologies for drudgery reduction of hill farm women

Inventory of all agricultural tasks depicted land preparation by women farmers as one of the most drudgery prone task with high energy cost, thereby, making it amenable to ergonomic interventions in terms of improved technologies (clod breaker, improved plough/'danella') to relieve women from high energy demands, time spent and associated drudgery. The study was conducted in two hill states of India viz. Himachal Pradesh (35 villages and 900 representative samples) and Uttrakhand (10 villages and 900 representative samples). Experimental data were conducted on representative sub sample of 60 hill farm women of both the states to assess physiological workload and musculo-skeletal problems both while working with traditional tools along with improved tools by employing selected parameters viz. physical fitness level, physiological parameters etc. The results showed that heart rate values were more than acceptable limits for task performed with the traditional tools as compared with improved tools. Significant reduction in the heart rate was observed while working with improved tools. Analysis of MSDs showed that the postural stress and severity of pain in various body parts was reduced by adopting new technology. Hence, the use of improved land preparation tools is recommended over the existing ones for drudgery reduction.     

Old scissors to industrial automation: the impact of technologic evolution on worker's health

To cut a fabric, the professional performs different jobs and among them stands out the cut. The scissors has been the instrument most used for this activity. Over the years, technology has been conquering its space in the textile industry. However, despite the industrial automation able to offer subsidies to answer employment market demands, without appropriate orientation, the worker is exposed to the risks inherent at the job. Ergonomics is a science that search to promote the comfort and well being in consonance with efficacy. Its goals are properly well defined and clearly guide the actions aimed at transforming the working conditions. This study aimed to analyze the activity of cut tissues with a machine by a seamstress and the implications on their body posture. The methodology used was the observation technique and application of the Protocol RULA, where the result obtained was the level 3 and score 5, confirming that "investigations and changes are required soon". Conclude that using the machine to tissue cut should be encouraged, but in conjunction with orientations for improving posture while handling it. It seeks to prevent dysfunction of the musculoskeletal system that prevents employees from performing their work tasks efficiently and productively.     

An ergonomic study on the biomechanical consequences in children, generated by the use of computers at school

This research deals with the influence of the computer use in schools related to the children posture, in an ergonomic point of view. The research tries to identify probable causes for the children early postural constraints, relating it to the sedentary behavior and the lack of an ergonomic project in schools. The survey involved 186 children, between 8 and 12 years old, students of a private school in Rio de Janeiro-Brasil. An historical and theoretical school furniture research was conducted as well as a survey with the students and teachers, computer postural evaluation, ergonomic evaluation (RULA method), and observations in the computer classroom. The research dealt with the student's perception with respect to the furniture utilized by him in the classroom during the use of the computer, his body complaint, the time he spent working on the school computer and the possibility of the existence of sedentariness. Also deals with the teachers' perception and knowledge regarding ergonomics with reference to schoolroom furniture and its Regulatory Norms (RN). The purpose of the research work is to highlight the importance of this knowledge, having in view the possibility of the teachers' collaboration in the ergonomic adaptation of the classroom environment and in their conscientious opinion during the purchasing of this furniture. A questionnaire was utilized and its results showed some discontent on the part of the teachers with relation to the schoolroom furniture as well as the teachers' scant knowledge of Ergonomics.We conclude with a survey that despite the children had constraints in postural assessments and school furniture needs a major ergonomic action, the time that children use the computer at school is small compared with the time of use at home and therefore insufficient to be the main cause of quantified commitments, thus the study of computer use at home as a development and continuity of this research.     

Ergonomic basket design to reduce cumulative trauma disorders in tea leaf plucking operation

Work related musculoskeletal disorders are seen as an indicating parameter of occupational stress among the women workers engaged in tea leaf plucking operation. The hand plucking (no mechanized plucking is practiced in Assam) being a highly repetitive task requires forceful exertions to reach to the distant periphery of the tea bushes and mechanical compression (pressing against hard surfaces). Specifically it aggravates with awkward positions adopted. The current research addresses to minimize the risk factors associated with CTDs and to ascertain the role of ergonomic design development in improving the situation. Women workforce engaged in tea industry in Assam suffer from back, shoulder, arm and finger pains. Workers perform the activity for 440 minutes in the entire shift with one hour lunch break in between in the garden itself. An ergonomic investigation aiming at studying the strain index of plucking operation in tea industry was conducted. While performing the operation workers were found to assume unnatural posture which is static as well as highly dynamic with a load (tea leaf collecting basket up to weight of 30 kg when filled with plucked leaves) at back. With gradual increment of load and pain though the load is released intermittently the strain level found to remain at a high level. The total QEC scores found for plucking activity was 110 out of 138. To improve the situation and to reduce the work related upper limb disorder (WRULD) an ergonomically designed basket was conceived and trial results showed improvements. The newly designed plucking basket fits the back curvature of the workers well, which keeps the basket in place unlike the existing round basket. The new basket is light in weight having more leaf capacity. Significant reduction in energy expenditure and MSDs suffered was observed while using improved basket over existing basket.     

Adoption of ergonomic features in a new reach truck cabin design--a usability study

The task of handling reach trucks frequently involves poor working postures. The location of the steering wheel in most reach trucks is in front of the operator which requires the drivers to bend forward and stretch their hands for holding onto the steering wheel. To overcome visibility restrictions, this posture is aggravated by twisting and bending their torso sideways. This paper presents a usability study which was conducted to compare adoption of ergonomic features in a new reach truck cabin with the way they were intended to be employed for improving physical working conditions. Participants drove the reach truck on a test track performing tasks of varying complexity. Video recordings were utilized to facilitate the observations. The results indicate that improved ergonomics features of the reach truck are not used as intended. The test subjects instead adopted postures that they were accustomed to when driving common reach trucks. The possible contributing factors to this posture regression are discussed. The procedure used in this study is recommended for the companies to determine the effectiveness and adoption of ergonomics solutions.     

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.     

Prevention of musculoskeletal disorders (MSDs) in office work: a case study

Twelve recently built office work stations, where jobs imply continued use of information and communication technologies, were analyzed for ergonomic risk factors. Based on a literature review of ergonomic recommendations for computer and general office work, a checklist was devised for assistance in identifying inadequate ergonomic situations, a process that was informed by pain complaints information. RULA (Rapid Upper Limb Assessment) was selected to estimate the risk of MSDs, considering the criteria of applicability and appropriateness to the case studied. This method was applied by an occupational health and safety technician to the most critical job observed in the workplace. Criticality was estimated through observations aided by the systematic use of a checklist tailored to the specific office scenario. Recommendations for change were provided for implementation in all workplaces in the office, in order to improve work conditions, and guide the setup of a MSD prevention training program.     

Design and implementation of ergonomic performance measurement system at a steel plant in India

Management of Tata Steel, the largest steel making company of India in the private sector, felt the need to develop a framework to determine the levels of ergonomic performance at its different workplaces. The objectives of the study are manifold: to identify and characterize the ergonomic variables for a given worksystem with regard to work efficiency, operator safety, and working conditions, to design a comprehensive Ergonomic Performance Indicator (EPI) for quantitative determination of the ergonomic status and maturity of a given worksystem. The study team of IIT Kharagpur consists of three faculty members and the management of Tata Steel formed a team of eleven members for implementation of EPI model. In order to design and develop the EPI model with total participation and understanding of the concerned personnel of Tata Steel, a three-phase action plan for the project was prepared. The project consists of three phases: preparation and data collection, detailed structuring and validation of EPI model. Identification of ergonomic performance factors, development of interaction matrix, design of assessment tool, and testing and validation of assessment tool (EPI) in varied situations are the major steps in these phases. The case study discusses in detail the EPI model and its applications.     

Multi dimensional system for evaluating preventive program for upper extremity disorders among computer operators

Typing is associated with musculoskeletal complaints (MSCs), caused by multiple risk factors. Although a wide variety of ergonomic intervention programs were conducted to reduce risk factors and MSC's, only few of them were found evidence based. This study aimed to test the efficacy of a workplace intervention in reducing MSC's among computer workers. 66 computer workers were assigned randomly to one of three intervention programs: ergonomic intervention including biofeedback, intervention without biofeedback and control group without intervention. The efficacy was tested by advanced assessment including; pain location and severity, posture at work, upper extremity 3D kinematics, muscle activity and psychosocial status. Working hypothesis; significant score differences will be found between the study groups which underwent ergonomic intervention and the control group on the following measures: pain complaints, upper extremity kinematics, muscle activity and psychosocial status. Significant differences were found between pre and post intervention and between research groups and the control group in pain, posture and motion. The ergonomic intervention with biofeedback had no unique contribution in comparison to other interventions. In conclusion; the proposed intervention program was found efficient for reducing pain among computer workers.     

Ergonomic risk assessment with DesignCheck to evaluate assembly work in different phases of the vehicle development process

Occupational hazards exist, if the design of the work situation is not in accordance with ergonomic design principles. At assembly lines ergonomics is applied to the design of work equipment and tasks and to work organisation. The ignoring of ergonomic principles in planning and design of assembly work leads to unfavourable working posture, action force and material handling. Disorders of the musculoskeletal system are of a common occurrence throughout Europe. Musculoskeletal disorders are a challenge against the background of disabled workers. The changes in a worker's capability have to be regarded in the conception of redesigned and new assembly lines. In this way ergonomics becomes progressively more important in planning and design of vehicles: The objective of ergonomic design in different stages of the vehicles development process is to achieve an optimal adaptation of the assembly work to workers. Hence the ergonomic screening tool "Design Check" (DC) was developed to identify ergonomic deficits in workplace layouts. The screening-tool is based on the current ergonomic state of the art in the design of physical work and relevant EU legal requirements. It was tested within a federal German research project at selected work stations at the assembly lines at Dr.-Ing. h.c. F. Porsche AG / Stuttgart. Meanwhile the application of the screening-tool DC is transferred in other parts of the Porsche AG, Stuttgart. It is also realized as an ergonomic standard method to perform assembly work in different phases of the vehicle development process.     

The effects of workstation changes and behavioral interventions on safe typing postures in an office

The purpose of the present study was to determine the effectiveness of an ergonomic and behavioral safety intervention for improving participants' safe typing postures in a library office setting. A single-subject multiple baseline design across five participants was employed to evaluate the effects of the four independent variables (workstation adjustment, equipment trial (rollermouse mouse alternative), peer observations, and graphic feedback). Six participant postures were observed repeatedly while participants worked at their workstations throughout the study. Each of the interventions resulted in improvements in safety for more than one posture compared to the previous phase. Results of the study indicate that a comprehensive ergonomic program that includes a workstation adjustment and a behavioral safety approach may be helpful to produce maximum improvements in employees' safe ergonomic postures.     

Ergonomic interventions in weeding operations for drudgery reduction of hill farm women of India

Weeding is an important time consuming and drudgery prone task mainly performed by hill farm women for almost all crops grown. This directs for interventions in terms of improved technologies (weeder, kutla and hoes) to relieve women from high energy demands, time spent and associated drudgery particularly for weeding activity. The study was conducted in two hill states of India viz. Himachal Pradesh (35 villages and 1500 representative samples) and Uttrakhand (10 villages and 500 representative samples). Experimental data were conducted on representative sub sample of 60 hill farm women of both states to assess physiological workload and musculo-skeletal problems both while working with traditional tools along with improved tools by employing selected parameters viz. physical fitness level, physiological parameters etc. The results showed that heart rate values were more than acceptable limits for task performed with the traditional tools as compared with improved tools. Significant reduction in the heart rate was observed while working with improved tools. Analysis of MSDs showed that the postural stress and severity of pain in various body parts was reduced by adopting new technology. Hence, the use of improved weeding tools is recommended over the existing ones for drudgery reduction.     

Maintenance of submersible pumps in the septic tanks: ergonomic and biological risks to the worker

In this study was observed the maintenance task of submersible pumps septic tanks installed in industrial bathrooms. This maintenance activity operators are exposed to various biological and ergonomic risks. This type of activity requires its great physical performers who are also subject to contact with human waste in the form of liquids, gases and solids. Besides the problems mentioned, are still exposed to high temperatures that can cause diseases such as hyperthermia or heatstroke. These aspects were observed using the ergonomic assessment methodology in order to suggest improvements that are reflected in productivity and employee satisfaction.     

Biomechanical modelling and evaluation of construction jobs for performance improvement

Occupational risk factors, such as awkward posture, repetition, lack of rest, insufficient illumination and heavy workload related to construction-related MMH activities may cause musculoskeletal disorders and poor performance of the workers, ergonomic design of construction worksystems was a critical need for improving their health and safety wherein a dynamic biomechanical models were required to be empirically developed and tested at a construction site of Tata Steel, the largest steel making company of India in private sector. In this study, a comprehensive framework is proposed for biomechanical evaluation of shovelling and grinding under diverse work environments. The benefit of such an analysis lies in its usefulness in setting guidelines for designing such jobs with minimization of risks of musculoskeletal disorders (MSDs) and enhancing correct methods of carrying out the jobs leading to reduced fatigue and physical stress. Data based on direct observations and videography were collected for the shovellers and grinders over a number of workcycles. Compressive forces and moments for a number of segments and joints are computed with respect to joint flexion and extension. The results indicate that moments and compressive forces at L5/S1 link are significant for shovellers while moments at elbow and wrist are significant for grinders.