Ergonomic Data Research Articles

Ergonomic Evaluation of Ride-on Tractor Operation between Beginner and Skillful Operator Comparative Analyses of Physiological Strain, Technical Performance and Viewing Point

The main objectives of this study are to provide ergonomic data about the performance of tractor operators, particularly beginners, and to find effective ways to improve operator-training system and work safety education.This paper reviews two experiments concerning ride-on tractor operation. Experiment 1 was the Driving Course (DC), which was designed to assess driving tasks in a road segment, and Experiment 2 was Rotary Tillage (RT), which was designed to assess tractor operation in a farm field. An ergonomic approach was taken to analyze the tractor operation performance of both beginners and skillful operators (all subjects have an automotive driver's license).The present study focused on comparative analyses of physiological strain, technical performance and viewing patterns between beginners and skillful operators. These analyses proved that the learning time required for beginners to reach a necessary level of performance and psychological stability were about 5 and 16 hours (effective-working time) for the driving course and rotary tillage operation, respectively.

A Monte Carlo investigation of dual-planar circular-orbit cone-beam SPECT

We use Monte Carlo simulations to study the imaging properties of a design for a dual-planar cone-beam (DPCB) single-photon emission computed tomography (SPECT) system. A dual-planar system uses a dual-camera SPECT system and two cone-beam collimators with foci in different axial planes to increase the effective axial field of view (FOV). We simulated nearly noise-free projection data from a computerized brain phantom and a phantom consisting of a series of points. Four configurations were simulated: parallel-beam low-energy high-resolution (LEHR) as a standard for comparison and DPCB at three radii of rotation (ROR) corresponding to the smallest, average and largest ROR required to clear patients' shoulders based on ergonomic data. We compared global measures of average resolution and total acquired counts for the four configurations. We also estimated local spatial frequency response for reconstructions of point sources. Finally, we estimated a local noise power spectrum by simulating 1000 noise realizations of the brain phantom and estimating a local noise covariance at selected points. The noise power spectra were used to estimate spectral signal to noise ratio (SNR) for each configuration. The resolution in the reconstructed image space ranges from 7.2 mm full-width at half-maximum (FWHM) at the minimum ROR to 9.4 mm FWHM at the maximum ROR. The efficiency is inversely related, ranging from 1.5 times that of parallel LEHR at minimum ROR to 2.5 times that of LEHR at maximum ROR. Estimates of system frequency response roughly correspond to the global resolution estimates, but the cone-beam techniques exhibit an unusual secondary peak in the axial-direction response. Estimates of spectral SNR show that the cone-beam configurations almost always result in higher SNR at all spatial frequencies regardless of ROR. The very largest ROR may be an exception. A larger ROR results in significantly higher SNR for low spatial frequencies with small reductions in SNR for mid-range frequencies. We conclude that the DPCB design allows significant improvements in both resolution and noise as compared to conventional parallel designs and that optimizing the ROR for the cone-beam system may improve the performance of certain imaging tasks.

Prioritizing Ergonomic Research in Aging for the 21st Century American Workforce

The Bureau of Labor Statistics predicts that by 2008 Americans aged 55 and over will represent the greatest annual growth rate and will occupy 30% of the American population. Additionally, by 2008 civilian labor force participation rates for the 55 and older group will grow to 36.8%, a 6.5% increase over the participation rates for this group for 1996, with the 55 to 64 age group expected to add 7.3 million workers. The predicted median age of the labor force for 2008 is estimated at 40.7 years, an age not approached because the median age peaked at 40.5 years in 1962. Coupled with this aging profile, employment in professional specialty occupations will increase the fastest and add the most jobs in the decade leading to 2008. Within the professional specialty professions, the majority of the employment increases are expected to occur in the service industry division. The purpose of this paper is to merge demographic data with ergonomic and human factors data and predictions to explore areas of ergonomic research that will aid in keeping the aging workforce, and those with whom they interact, healthy in their jobs and keep the companies for whom they are employed competitive. Although some ergonomics research has been conducted in all the listed areas of expected growth, the paper reexamines the job demands in each sector, with a focus on the needs of the aging workforce.

Why do women suffer from sick building syndrome more often than men?--subjective higher sensitivity versus objective causes.

Office workers often report so-called sick building syndrome (SBS) symptoms affecting the skin, mucous membranes and nervous system. The recurring higher prevalence of SBS in women was investigated using questionnaire and ergonomic data from the German ProKlimA-Project. The hypothesis that working conditions and job characteristics for women are inferior to those of men was tested for groups of risk factors. Finally, gender-specific multiple logistic regression models were compared. It was found that 44.3% of women (n = 888) and 26.2% of men (n = 576) suffer SBS with significant differences between men and women for many variables. Considering sub-groups--supposing the same circumstances in psycho-social and work-related conditions--gender-specific SBS prevalence rates differ as for the whole sample, e.g. 35.9% of women with the most favourable job characteristic suffer SBS (men: 19.4%), 53.0% of women with the most unfavourable job characteristic suffer SBS (men: 33.3%). These results show that women suffer more SBS than men independent of personal, most work-related and building factors. Multiple logistic models define self-reported acute illness, job satisfaction, software quality and job characteristics as significant gender-independent risk factors. Number of persons/room, self-reported allergy and smoking are characteristic female risk factors. Age is a significant risk factor only in men.

The Use of Ergonomic Concerns Data as a Proactive Input to the Design of Workplace Tools

The Ford Motor Company has recorded over 5606 ergonomic concerns relating to job hazards through their automated evidence book ErgoRx. As part of a review of the ergonomics process in Ford, a study was carried out to look at the transfer of ergonomic information between division process engineers and plant ergonomics personnel. The study focused on ergonomics training and background knowledge, and Ford tools used to provide ergonomics information and the feedback processes. Issues on the effective feedback of ergonomics data early on in the design process are of particular interest in the light of the recent repeal of the OSHA Ergonomics regulation. Instead of using reportable ergonomics concerns to trigger remedial actions, concerns can be reduced by designing-out the features that cause the problems. Used in this way concerns data, as well as existing ergonomics tools, can be used as a cost effective, proactive input in new and redesign activities. This approach, used more widely, could be an effective way of removing objections to the imposition of a difficult to apply, and largely reactive ergonomics regulation.

The creation of ergonomic data sheets for hazard communication of work-related musculoskeletal disorders.

Information on human health hazards caused by chemical exposure has traditionally been supplied through Material Safety Data Sheets (MSDS). This report describes development of an analogous Ergonomic Data Sheet (EDS) to address hazards of work-related musculo-skeletal disorders (WRMSD) from use of hand tools. The EDS includes sections on risk factors for WRMSD, design aspects of the tool that decrease risks, precautionary measures, and objective testing of the tool compared to other comparable tools. The EDS can be used within an Ergonomic Communication Program similar to a Hazard Communication Program.

Ergonomic Redesign of a Commercial Tool Handle

Many commercial hand tools have been designed without ergonomic principles in mind which can result in the occurrence of upper extremity trauma. In this study, therefore, a clamping hand tool, Quick-Grip® bar clamp, was selected, ergonomically evaluated, a new version of the clamp focused on the handle was developed, and the original and ergonomically designed versions were compared using survey questionnaire. Design processes of the development of a new version were evaluation of the original clamp regarding ergonomic guidelines and anthropometric data, an idea sketch, prototype development, drafts and rendering of new design, development of final model, and objective and subjective comparisons to the original handle. Eleven male and eleven female students participated in the subjective testing portion which entailed questions after finishing simulated work. The results revealed that subjects were satisfied with the new version that was comfortable to hold and use in any position due to the rounded shape, the handle dimensions were appropriate, and no subjects reported pain in the hand. This study shows that application of ergonomics principles to the design of hand tools could increase usability and value of products and should be considered by manufacturers and designers.

Representative Video Recordings for Synchronized Collection of Ergonomic and Production Data in an Assembly System

A method has been developed for optimized representative video recordings for synchronized collection of ergonomic and engineering data in assembly systems using the same film. The method is based on random selection of both operators and starting time of the recordings during the day with some boundary conditions: fixed total recording time (30h) and an upper (3h) and lower (1h) recording time per operator. The method was tested at an electronic assembly industry. The study showed that the method has to be further developed. This development would be on basis of statistical models assessing associations between measurement resources, representativeness and precision as functions of working hours, number of work stations, manning and work rotation.

Prioritizing Ergonomic Research in Aging for the 21st Century American Workforce

The Bureau of Labor Statistics predicts that by 2006 Americans aged 55 and over will represent the greatest annual growth rate and will occupy nearly 30% of the American population. Additionally, by 2006 civilian labor force participation rates for the 55 and older group will grow to 36.8%, a 6.5% increase over the participation rates for this group for 1996, and over three times the percent increase of the next highest group (25 to 54 years; 1.7%). The predicted median age of the labor force for 2006 is estimated at 40.6 years, an age not approached since the median age rose to 40.5 years in 1962. Coupled with this aging profile, professional specialty occupations and service occupations are expected to provide nearly half of the total job growth during the decade leading to 2006. Within the professional specialty professions, nearly 90% of the employment increases are expected to occur in the service industry division, led by educational services and health services. The four industry sectors projected to produce the largest job growth are retail trade, business services, health services, and educational services. In contrast to the increases in the service and business sector, the manufacturing sector is expected to experience a loss of jobs, particularly for operators, fabricators, and laborers. The purpose of this paper is to merge demographic data with ergonomic and human factors data and predictions to explore areas of ergonomic research that will aid in keeping the aging workforce, and those with whom they interact, healthy in their jobs and keep the companies for whom they are employed competitive. Although some ergonomics research has been conducted in all the listed areas of expected growth, a return to the examination of the job demands in each sector, with an eye to particular application to the aging workforce, is important. The retail trade sector requires of the employee cognitive and visual skills, processing skills, and VDT work. It is expected that displays will continue to be studied to improve interaction and reduce glare. In addition, the increase in transportation jobs associated with business and trade, and the inclination for older baby boomer generation to continue driving will spur research on glare, displays, vibration, temperature, cognition, and psychomotor skills. Within the health services sector, the increase in the need for home health care will increase the number of older workers employed in this area, a change that will necessitate building upon the research already conducted on individual health and the ergonomics of work and the work environment in home settings. Educational services, especially for the changing workforce and the young workforce, will entice the aging into this field and promulgate new paradigms for training and work organization.

Test and Evaluation of Work Places and Products with WIN EDS 2000 (A First Bilingual Database System of Ergonomics)

Even though a large amount of ergonomic data and recommendations are available, tools, equipment and products are quite frequently subject to considerable ergonomic deficiencies. The reason for this is that knowledge of ergonomics is not as widespread as the expert would like it. The designer of work places and equipment usually has a rather small background of ergonomics. In many cases it is difficult even for the ergonomist to compress the available knowledge into tables and charts. A computerised assistance system could be of great help

Ergonomic evaluation of complex work: a participative approach employing video–computer interaction, exemplified in a study of order picking

A method for ergonomic evaluation of complex manual work was developed, based on interactive operator assessment of video recordings. The video film is displayed on the computer terminal, and the filmed operator assesses the work by clicking on virtual controls on the screen, whenever a situation inducing pain or discomfort appears. The operator marks body region and rates perceived exertion. In this way, a filmed sequence covering hours of work is condensed into a limited number of high-priority tasks. A library is formed in the computer, including task and operator identification data, ergonomic data, and pictorial information. The evaluation system, called VIDAR, was applied in an application study of manual materials handling in an automotive workshop. Results showed that the subjects after a brief instruction were able to understand and provide input to the system. The assessments were reasonably consistent in the group of operators. It was concluded that VIDAR provides data that are highly useful in a participatory process of change, and that it adds a new dimension to ergonomic evaluation of complex work. Cognitive aspects calling for further scientific study were identified. Relevance to industry Existing expert-based observation methods are sometimes difficult to apply in practice. The method described here is based on operator rather than expert assessment, which provides structured information that is relevant and useful, for instance in industrial interventions.

Design-relevant ergonomic data on Dutch elderly

The design of daily-life products that can be used in a safe and comfortable way by many consumers requires ergonomic data concerning these users. With regard to the elderly, hardly any ergonomic data were available. In this study, measurements were done on about 79 physical, psychomotor, sensory and cognitive variables. The sample consisted of 750 persons: 123 in the age between 20 and 30 years and 623 aged 50 years and over. The results reveal different patterns of level and variation with age. Generally speaking, the physical data exhibit a relatively small variation with age; in other words, the variation within age groups is much larger. For the psychomotor and sensory variables variance generally increased with age. Especially after the age of 65 or 70 the level of performance decreased compared to that of younger subjects. As far as differences between the sexes are concerned, it is concluded that there are marked differences in the physical variables between males and females. Body build and the amount of force exerted differ. The psychomotor variables also show systematic differences between men and women. For the sensory and cognitive variables, few systematic differences between the sexes were found. People with capacities in the lower percentiles of the frequency distribution appear to have difficulties in performing daily-life activities. However, they still manage to live independently. This is possible because they use all kinds of solutions to compensate for the lower level of ability.

An Ergonomic Walkthrough Observation of Carpentry Tasks: A Pilot Study

Abstract The purpose of this pilot study was to determine the ergonomic risk factors for cumulative trauma disorders associated with carpentry tasks. Twenty-one union carpenters were observed on 29 occasions at 17 different construction sites. The job specialties observed were ceiling, drywall, and concrete form. A checklist for ergonomic walkthrough surveys was developed for this study. The carpenters were observed and videotaped while performing routine tasks. Based on the ergonomic walkthrough checklist data and video data, the three job specialties were rank-ordered by the scores obtained for posture and repetition. Based upon the combined score of postures from the three specialties, the most stressful postures were used by the neck/shoulder region, followed by the elbow and the back regions. In comparison to the drywall and ceiling tasks, the formwork tasks produced the most stressful postures for the hip/leg, back, and elbow regions. For the ceiling tasks, the most stressful postures were found to ...

Ergonomic data of elderly people and their application in rehabilitation design

The population of the First World is ageing, and as it does so elderly people are becoming an increasingly significant consumer group. This process has important ramifications for the ergonomics and design professions. The demand for products that have been developed with consideration for the elderly consumer will require designers to develop new skills and ergonomists to supply new data. This paper highlights the inadequacy of current design data pertaining to the elderly. Anthropometric studies which have been carried out within the fields of ergonomics and rehabilitation are reviewed, and their usefulness to the product designer discussed. Recommendations are made regarding future needs for the collection and dissemination of further data.

Forces in the hand-arm system: Investigations of the problem of left-handedness

With the exception of few investigations, left-handed individuals have not been considered in the ergonomic design of products and places of work. About 15% of the population is left-handed. There is, therefore, a big need for ergonomic data for lefthanders. The importance of such data is also demonstrated by the fact that the percentage of lefthanders in the population will continue to increase in the future. In this paper, maximum operational force data of the human hand-arm system are provided. Results of the investigations are: (a) Lefthanders have nearly the same maximum operational force in both hand-arm systems; (b) The values for the maximum static force, recorded in norms, are also valid for lefthanders; (c) Righthanders are less universally employable.

Work related upper limb disorder: the relationship between pain, cumulative load, disability, and psychological factors.

Repetitive strain injury, or work related upper limb disorder, provides an interesting paradigm for the study of the relative contribution of physical and psychological factors to the resulting pain and disability. Sixty three subjects were studied, comprising the work-force of a subsection of a large local industrial company, in whom pain in the arm related to work was known to be common. Ergonomic data were obtained by estimating the cumulative daily load on the wrist joint for each of four identified tasks. Data on the occurrence of pain, treatment sought, and disability were obtained by a structured self administered questionnaire. Psychological data were obtained by administering the Hospital Anxiety and Depression (HAD) scale, a self reported measure of anxiety and depression, and the Bradford Somatic Inventory (BSI), an inventory of somatic symptoms associated with anxiety and depression. The employment specific period prevalence of work related upper limb disorder was 81%, with 30% of the subjects having pain at the time of the study. Domestic disability was minimal in all but two subjects, though the use of devices such as jar openers at home was common (12 of 51 subjects). Medical advice was seldom sought. Twenty per cent of subjects had received anti-inflammatory drugs, 10% had received physiotherapy, and 47% had wrist splints. Pain was related to the tasks with the highest estimated daily loads, but a history of pain and current pain were associated with higher scores on the HAD and BSI scales, suggesting an interaction between physical and psychological factors.

Working conditions and weil‐being among women office workers

In 1983 the National Institute for Occupational Safety and Health launched a comprehensive study of the relationship of working conditions to health and well‐being among women office workers, in the context of women's dual roles as employees and family members. Extensive questionnaire, interview, and ergonomic data were collected in 1985. This report presents data from the questionnaires of 625 women office workers at four work sites—public and private—in the United States.

The Design Assisting System Based on Ergonomic Data

The Design Assisting System Based on Ergonomic Data

Computer-Aided Human Factors for Systems Designers

Over the past decade, a multi-phased project supported by agencies of the Department of Defense, FAA, and NATO has been underway to understand and remediate problems in the transitioning of ergonomic research to system design applications. Efforts to enhance the usability of ergonomic data in system design have resulted in the present R&D project, which is concerned with developing a multi-media ergonomics database on CD-ROM. The Computer Aided Systems Human Engineering (CASHE) system, Version 1.0, will contain the Boff and Lincoln (1988) Engineering Data Compendium, MIL-STD-1472D and the Perception & Performance Prototyper. The Perception & Performance Prototyper will allow the user to experience and manipulate the technical data found in the Compendium and MIL-STD-1472D. The CASHE tool will also include specialized data retrieval, scaling, and analysis capabilities as well as state-of-the-art in information retrieval, browsing, and navigation.

Colony ergonomics for a desert‐dwelling bumblebee species (Hymenoptera: Apidae)

Abstract. Data on worker traffic, size and concentration of nectar loads, and size and composition of pollen loads were collected for a colony of Bombus pennsylvanicus sonorus Say in the Chihuahuan Desert in Arizona, U.S.A. Foraging activity increased through the morning to a peak level in early afternoon and then declined steadily thereafter. Pollen collection occurred primarily in the morning, whereas nectar was harvested throughout the day. Nectar loads decreased in size but increased in sugar concentration during the day. Following field observations, we excavated the nest and counted the numbers of immatures and adults present and measured the honey and pollen reserves. A total of 150 workers were present, and we estimate that the colony would have produced 174 queens and 192 males. Food reserves appeared small: pollen and honey stored in the nest represented only 18% and 35%, respectively, of the daily input. These results are compared to ergonomic data collected for B.vosnesenskii in the only other similar study.