Prescription ergonomics: adding prevention to the diagnosis and treatment of work-related musculoskeletal disorders.
(65/527)
The physician treating patients who have work-related musculoskeletal disorders (WMSDs) must educate the patient and employer about the nature of the problem and what to do about it. To do this effectively, diagnostic findings must be linked to prevention efforts in a way that is understandable for the physician, the patient, and the company's safety professional. Three skills are required. First, the physician must be able to recognize how the injury presentation reflects acute or chronic biomechanical stress patterns. Second, the physician must be able to recognize the work relationships and other elements that influence biomechanical stress. Third, the physician must have access to a mnemonic that enables him or her to analyze the work method and explain significant findings to the patient and employer. (+info)
Active epidemiological surveillance of musculoskeletal disorders in a shoe factory.
(66/527)
AIMS: (1) To evaluate an active method of surveillance of musculoskeletal disorders (MSDs). (2) To compare different criteria for deciding whether or not a work situation could be considered at high risk of MSDs in a large, modern shoe factory. METHODS: A total of 253 blue collar workers were interviewed and examined by the same physician in 1996; 191 of them were re-examined in 1997. Risk factors of MSDs were assessed for each worker by standardised job site work analysis. Prevalence and incidence rates of carpal tunnel syndrome, rotator cuff syndrome, and tension neck syndrome were calculated for each of the nine main types of work situation. Different criteria used to assess situations with high risk of MSDs were compared. RESULTS: On the basis of prevalence data, three types of work situation were detected to be at high risk of MSDs: cutting, sewing, and assembly preparation. The three types of work situations identified on the basis of incidence data (sewing preparation, mechanised assembling, and finishing) were different from those identified by prevalence data. At least one recognised risk factor for MSDs was identified for all groups of work situations. The ergonomic risk could be considered as serious for the four types of work situation having the highest ergonomic scores (sewing, assembly preparation, pasting, and cutting). CONCLUSION: The results of the health surveillance method depend largely on the definition of the criteria used to define the risk of MSDs. The criteria based on incidence data are more valid than those based on prevalence data. Health and risk factor surveillance must be combined to predict the risk of MSDs in the company. However, exposure assessment plays a greater role in determining the priorities for ergonomic intervention. (+info)
A method for reducing adaptor misalignment when testing gloves using ISO 10819.
(67/527)
OBJECTIVES: International standard ISO 10819 was established in order to quantify the vibration attenuation characteristics of anti-vibration gloves. One problem that exists with the standard is possible misalignment of the palm adaptor that is placed underneath the test glove. If the adaptor becomes misaligned, the measured glove transmissibility will be lower than the actual value. A tri-axial accelerometer was installed in the adaptor and was used as the basis for providing visual feedback of the adaptor alignment to the test subjects. The objective of this study was to test the hypothesis that adaptor misalignment could be reduced by providing feedback to the test subjects. METHODS: Eight male volunteers (mean age 24.8 yr) were used in the study. Each subject performed two sets of tests: the standard ISO 10819 glove test and the modified version. Three different anti-vibration gloves were tested. Glove transmissibility and adaptor misalignment were calculated for each glove. A three-way analysis of variance was used to analyze the results. RESULTS: A comparison of the two testing methods showed that the modified glove testing method did reduce misalignment significantly, which, in turn, resulted in an increase in the measured glove transmissibility. CONCLUSIONS: The proposed method greatly improved the standard deviation of transmissibility and made the test results more consistent. (+info)
Evaluation of different scales for measurement of perceived physical strain during performance of manual tasks.
(68/527)
The main objective of this study was to evaluate different scales of perceived strain during the performance of various physical tasks. A total of 52 male and female participants took part in 4 experiments to achieve the study objective. The results suggest that a bipolar comfort-discomfort scale is a more appropriate instrument than a discomfort scale for assessing cumulative physical stresses at work, especially at the beginning of the shift. For assessing discomfort at the end of the work shift, a unipolar scale may also be used. On the basis of the obtained results, red, green, and yellow zones are suggested to establish priorities for work redesign efforts in ergonomic control programs. (+info)
Ergonomic program effectiveness: ergonomic and medical intervention.
(69/527)
The implementation of a successful ergonomic and medical intervention program designed to reduce the number and severity of injuries and illnesses and the associated levels of discomfort in the workplace is presented. Because of the recent activity concerning the on-again-off-again Occupational Safety and Health Administration (OSHA) Ergonomic Program Standard questions have been raised as to the value and effectiveness of an organization's ergonomics program. In light of these concerns, the immense cost associated with work-related injury and illness, and the related pain and suffering associated with such injuries and illnesses, it is important to present a workable and effective ergonomic and medical intervention program. The results of this applied study demonstrate that through the application of an ergonomic and medical intervention program, workplace-related injuries and illnesses can be reduced or eliminated. (+info)
Combining psychophysical measures of discomfort and electromyography for the evaluation of a new automotive seating concept.
(70/527)
The purpose of this study was to determine if the advantages and disadvantages of a new automotive seating concept, known as the micro-adjuster control system, could be reliably evaluated using both a physiological assessment technique (i.e., electromyography [EMG]) and a subjective questionnaire. The results indicate that psychophysical measures of discomfort and the root mean squared (RMS) activity of the EMG are statistically related, r (8) = -.788, p =.020. More specifically, subjective perceptions of comfort were found to improve with decreasing levels of muscle activity. This implies that seat comfort can be evaluated on the basis of physiological as well as subjective responses to prolonged driving. This finding should drastically improve automobile seat design efforts. (+info)
Three-dimensional lifting model for non-homogeneous loads.
(71/527)
A 3-dimensional model and analysis methodology is suggested for treating lifting tasks when unbalanced loads are involved. The paper describes the biomechanical equations that are coupled with the worker's posture geometry, to address a practical problem of non-symmetric lifting. The analysis has a dominant biomechanical modeling scope, as it contains a breakdown of the internal lifting forces resulting from posture and external loads acting on the body. The load model represents the acting forces due to unbalanced lifting, which is commonly found in industrial situations. The suggested model allows the user to simulate the influence of the practical load distribution, aiding safe design of a lifting job. (+info)
In-vehicle communication systems: the safety aspect.
(72/527)
Communication and information technology are developing very rapidly at present. At the same time, the number of older drivers is increasing. When designing systems for elderly drivers, it has been shown that: (1) simplifying a task reduces performance differences between old and young; and (2) the optimization of onboard systems (better legibility and intelligibility of the information, simplified dialogue) in relation to the abilities of elderly drivers benefits the rest of the user population. Elderly people do not automatically reject new information and assistance technologies especially when the systems are user friendly. However, the ergonomics of these new technologies must be studied, with particular attention to the specific needs of the elderly, in order not to marginalize them (+info)