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FD CEN ISO/TR 19664 - Réponse des individus aux vibrations
Recommandations et terminologie pour les instruments et l'équipement d'évaluation de l'exposition quotidienne aux vibrations sur le lieu de travail selon les exigences de santé et de sécurité L'évaluation de l'exposition des individus aux vibrations transmises à la fois au niveau du système main-bras et au niveau de l'ensemble du corps, sur le lieu de travail, repose sur l'évaluation combinée des amplitudes de vibration et des temps d'exposition. Plusieurs types d'instruments et sources de...
Cumulative occupational mechanical exposures during working life and risk of sickness absence and disability pension
Prospective cohort study Using a biomechanical job exposure matrix combined with Danish registers, cumulative occupational mechanical exposures throughout life (ie, more years with heavy and frequent lifting, and kneeling work) predicted risk of long-term sickness absence among older workers. Importantly, heavy lifting throughout working life was associated with disability pension. Source: Sundstrup E, Hansen ÅM, Mortensen EL, Poulsen OM, Clausen T, Rugulies R, Møller A, Andersen LL. (2017). Scand J Work Environ Health . http://dx.doi.org/10.5271/sjweh.3663
Risque vibratoire chez les opérateurs d’engins mobiles
Cartographie des postures et des vibrations au poste de conduite Les opérateurs d'engins mobiles sont exposés à des vibrations de l'ensemble du corps susceptibles d'être à l'origine de troubles du rachis. La procédure actuelle d'évaluation du risque vibratoire ne tient pas compte de la position et des mouvements du corps des conducteurs. Ces paramètres sont aujourd'hui considérés comme des cofacteurs importants. Pour cette raison, l'INRS mène des travaux de recherche visant à mettre au...
Association Between Farm Machinery Operation and Low Back Disorder in Farmers
A Retrospective Cohort Study Objective: The association between whole body vibration (WBV) as measured by annual accumulated use of all-terrain vehicles (ATV)/combine/tractor operation and low back disorders (LBDs) among farmers was investigated. Methods: Saskatchewan Farm Injury Cohort Study data was used. Baseline data were collected in 2007 on the three vehicle types and other factors. Follow-up data on LBD symptoms were collected during 2013 resulting in 1149 samples. Results: Adjusted for age, education, and gender, LBDs were associated with tractor operation for 1 to 150 hours/year (Relative...
Étude exploratoire sur la caractérisation de la masse apparente d’un système couplé corps assis
Siège élastique soumis à des vibrations dans l'axe vertical Cette étude explore un système de mesure à pellicule mince de la pression à l'interface corps-siège (Tekscan Inc.) pour caractériser les réponses biodynamiques de sujets humains assis sur des sièges élastiques et exposés à des vibrations dans l'axe vertical. L'étude porte sur un siège rigide et trois sièges élastiques : un siège constitué d'un bloc de mousse de polyuréthane...
Calculette vibration ensemble du corps
Cette calculette au format Excel permet d'évaluer l'exposition quotidienne aux vibrations transmises à l'ensemble du corps par les engins mobiles. A partir des données vibratoires connues au préalables (mesures ou bases de données, suivant les 3 directions ou l'axe dominant), elle permet de calculer rapidement et facilement l'exposition vibratoire journalière A(8) d'un conducteur, et ceci même si ce dernier utilise plusieurs engins dans sa journée. Les résultats donnés par la calculette permettent de situer...
Predicting and controlling risks from human exposures to vibration and mechanical shock
Flag waving and flag weaving At work or in leisure activities, many people are exposed to vibration or mechanical shocks associated with risks of injury or disease. This paper identifies information that can be used to decide whether there may be a risk from exposure to hand-transmitted vibration or whole-body vibration and shock, and suggests actions that can control the risks. The complex and time-varying nature of human exposures to vibration and shock, the complexity of the different disorders and uncertainty as to the mechanisms of injury and the factors influencing injury have prevented the...
Whole body vibration exposures in bus drivers: A comparison between a high-floor coach and a low-floor city bus
Low back pain (LBP) is common in occupational bus drivers and studies have shown a dose–response relationship between whole body vibration (WBV) exposure and LBP. Bus design may be an important factor in determining the WBV exposure a bus driver receives. The purpose of this study was to determine whether differences exist in WBV exposures between two buses commonly used in long urban commuter routes: a high-floor coach and a low-floor city bus. Each bus was driven over a standardized test route which included four road types: a newer smooth freeway, a rougher old freeway, a city street segment...
Identification of quality attributes of automotive idle sounds and whole-body vibrations
The aims of this study are the generation and comparison of the semantic spaces of vehicle idling sounds and vibrations and the determination of their quality dimensions. In this study, two different sets of quality attributes were developed for idling sounds (34 attributes) and whole-body vibrations (22 attributes). In contrast to prior investigations, the results demonstrated that the sound level alone is an insufficient attribute for describing the complexity of idle sounds and vibration perceptions. The qualities of both idle sounds and idle vibrations have multidimensional, complex characters...
Comprehensive measurement in whole-body vibration
Accurate measurements of human response to whole-body vibration are essential to any conclusions about the health risks, discomfort, and assessment of suspension systems in vibration environments. While accelerometers are traditionally considered the main measurement tools in whole-body vibration studies, their measurements become questionable when they are attached to inclined surfaces or when the motion has coupled components in multiple directions. Current measurement correction methodologies are subjective and limited to simple cases. A comprehensive correction methodology using inertial sensors...
Predicting discomfort from whole-body vertical vibration when sitting with an inclined backrest
Current methods for evaluating seat vibration to predict vibration discomfort assume the same frequency weightings and axis multiplying factors can be used at the seat surface and the backrest irrespective of the backrest inclination. This experimental study investigated the discomfort arising from whole-body vertical vibration when sitting on a rigid seat with no backrest and with a backrest inclined at 0° (upright), 30°, 60°, and 90° (recumbent). Within each of these five postures, 12 subjects judged the discomfort caused by vertical sinusoidal whole-body vibration (at frequencies...
Six-degrees-of-freedom measurement to select operator seats based on industry specific field vibration characteristics
The purpose of this paper was to quantify in (6DOF) whole-body vibrations during the daily operating tasks of 5 commonly used mobile machines types used in the steel making and metal smelting industries. Elevated values were observed at the chassis for crest factors, peak running root mean squared accelerations, and vibration total values, resulting in ISO 2631-1 (1997) comfort predictions ranging from Uncomfortable to Extremely Uncomfortable. Vibration dominant frequencies were generally between 1 and 8Hz. A second peak which occurred at approximately 27 Hz was observed for each vehicle in almost...
Considerable differences in the transmissibility measurements of whole-body vibration without proper correction
Accurate measurements of human response to whole-body vibration are essential to any conclusions about the health risks, discomfort, and assessment of suspension systems in vibration environments. While accelerometers are traditionally considered the main measurement tools in whole-body vibration studies, their measurements become questionable when they are attached to inclined surfaces or when the motion has coupled components in multiple directions. Current measurement correction methodologies are subjective and limited to simple cases. A comprehensive correction methodology using inertial sensors...
Exposure of suspended cabin tractor semi trailer drivers exceeds the upper limit for an 8-h work day
This paper presents a study on whole body vibration analysis for drivers of tractor semitrailers. The tractor semitrailer, namely, a suspended cabin tractor semitrailer was considered for the present investigation. The important process parameters such as different speeds, different road surfaces and different loaded conditions with driver seat interface acceleration in X- longitudinal, Y transverse and Z-vertical axes were tested. The average running weighted root mean square accelerations obtained after conducting the experimental work were between 0.6265 and 1.5594 m/s2 at the driver seat interface...
Réduction des vibrations au poste de conduite des engins de chantier : Travailler sans secousse
Les conducteurs et opérateurs d'engins de chantier sont régulièrement exposés à des vibrations et chocs transmis à l'ensemble du corps par le siège et le plancher. Pour la plupart des engins, l'exposition est au-dessus de la valeur d'action définie par le décret n° 2005-746. Dans certains cas, la valeur limite peut être dépassée. Ce guide introduit une démarche générale, pour réduire le risque vibratoire, qui est reprise en trois fiches spécifiques aux familles...
The vibrotactile perception threshold changes were greatest after simultaneous exposure to both WBV and HAV
This article presents the results of laboratory tests on the combined effect of whole-body vibration (WBV) and hand–arm vibration (HAV). The reactions of subjects exposed to various combinations of vibration were recorded. The vibrotactile perception threshold (VPT) test identified changes caused by exposure to vibration. Ten male subjects met the criteria of the study. There were 4 series of tests: a reference test and tests after exposure to HAV, WBV, and after simultaneous exposure to HAV and WBV. An analysis of the results (6000 ascending and descending VPTs) showed that the changes in...
Exploring how anthropometric, vehicle and workplace factors influence whole-body vibration exposures during on-farm use of a quad bike
The primary aim of this study is to determine whether a combination of body height, terrain and vehicle mechanical factors confound for the effect of body mass on WBV exposure while using a quad bike under normal rural working conditions. A seat pad mounted triaxial accelerometer and data logger recorded full work day vibration and shock data from 130 New Zealand rural workers. Personal, vehicle and workplace characteristics were gathered using a modified version of the Whole Body Vibration Health Surveillance Questionnaire. Whole-body vibrations were analysed in accordance with the ISO 2631-1...
Reducing whole-body vibration exposure in backhoe loaders by education of operators
Whole-body vibration is a health hazard for operators of construction machinery. The level of whole-body vibration exposure on the operator is governed by three different factors; performance of the suspension system of the machine, planning of the work and the skills of the operator.In this research work it is investigated whether there is a potential in bringing down the level of whole-body vibration exposure by educating operators of backhoe loaders. This is carried out by an experimental setup. Six experienced operators participated in the experiments carried out on two different sizes of backhoe...
Apparent mass and head vibration transmission responses of seated body to three translational axis vibration
The apparent mass and seat-to-head vibration transmissibility response functions of the seated human body were investigated under whole-body vibration exposures to fore-aft (x), lateral (y), and vertical (z) applied individually and simultaneously. The experiments were performed with 9 adult male subjects to measure the biodynamic responses to single and uncorrelated three-axis vibration with and without hands and back supports under different magnitudes of random vibration in the 0.5–20Hz frequency range. The apparent mass and the head vibration transmission responses were derived using...
Optimisation of whole body vibration analysis for suspended cabin tractor semitrailer
This work has been conducted to find out the health risk associated with suspended cabin tractor semi-trailer driving work. Suspended cabin tractor semi-trailer drivers are exposed to whole body vibration (WBV) during their work. Some drivers suffer from low back pain caused by vibration. The practical significance of applying suspended cabin type of tractor semi-trailer was tested at different road conditions, different speeds as well as different load conditions for comfortable driver seat interface (x, y, z axes) and the ride comfort parameters have been prioritised using Taguchi's L27 orthogonal...
Vibrations, exiguïté, faible marge de manoeuvre
Comment améliorer le poste de conduite du métro de Montréal? Ce document est destiné aux intervenants en santé et en sécurité du travail, aux ergonomes, aux ingénieurs et à toute personne concernée par l'amélioration d'un poste de travail dans un contexte de faible marge de manoeuvre. Il décrit sommairement tant la démarche technique que la collaboration qui ont permis d'améliorer le poste de conduite du métro de Montréal dont le siège, l'espace restreint et les...
The presence of a backrest changes the biodynamic response of the seated body and should be taken into account
This study investigated the apparent mass and cross-axis apparent mass of the human body exposed to random vibration (0.2 to 20 Hz) in all 15 possible combinations of four magnitudes (0, 0.25, 0.5 and 1.0 ms–2 r.m.s.) of fore-and-aft vibration and the same four magnitudes of vertical vibration. The human body has a nonlinear response to wholebody vibration: a softening response as the magnitude of vibration increases. The nonlinearity is apparent when the body is excited at varying magnitudes of single-axis vibration and when the body is excited by a fixed magnitude of vibration in one axis...
An approach to the control system design of seat suspension systems for the active vibration attenuation
This paper presents an approach to the control system design of seat suspension systems for the active vibration attenuation. The paper presents the studies of the active vibration control strategy based on the reverse dynamics of force actuator and the primary controller. The multi-criteria optimization procedure is utilized in order to calculate the primary controller settings which subsequently define the vibro-isolation characteristics of active suspensions. As an example of the proposed control system design, the seat with a pneumatic suspension is investigated and its vibro-isolation properties...
Évaluation de l'exposition aux vibrations globales du corps chez les opérateurs de compacteurs de sol
L'exécution de travaux routiers et de compactage de sols se fait généralement à l'aide de compacteurs vibrants monocylindres (à rouleau compresseur). Or, ces engins exposent les opérateurs à des niveaux de vibrations globales du corps élevés, reconnues comme un facteur de risque du développement de lombalgies. Seules quelques études européennes ont jusqu'ici caractérisé leurs vibrations, lesquelles dépassent parfois la limite maximale d'exposition quotidienne. Cette activité...
Whole body- vibration (WBV) levels remained just above ISO 2631-1 after being optimized for load-haul-dump (LHD) vehicles
Operators of load-haul-dump (LHD) vehicles are commonly exposed to wholebody- vibration (WBV) levels above ISO 2631-1 and EU Directive 2002/44/EC guidelines. Vibration exposure was lowest when the LHD was driven at the lowest speed, forward, over smooth terrain, with ride control on and the bucket loaded (0.20 m/s 2 ). The A(8) decreased from 0.84 m/s 2 when driving with ride control off, over mixed terrain using all gears, to 0.53 m/s 2 when driving with ride control on and an optimized seat. The estimated daily exposure decreased but remained just above the ISO 2631-1 and EU Directive 2002/44...
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