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The specific aims of this study are to examine the rationale behind the major revisions of the ISO standard of the anti-vibration (AV) glove test and to evaluate the major technical aspects of the revised method through an experiment. While this study failed to realize the constant-velocity spectrum proposed in the original revision, the glove vibration transmissibility values measured with a new spectrum proposed in the current study were very similar to those measured with the M and H spectra defined in the current standard, which suggests the new spectrum can greatly simplify the test without...
This article explain that vibration injury is typical of the «slow accidents» that build through continued exposure to the so-called physical agents, which also include noise and radiation... damages many lives. It presents the syllabus of the NEBOSH National Diploma «Physical agents» and resumes information on Whole-body vibration and Hand-arm vibration. In his series for NEBOSH National Diploma students, Lawrence Bamber details the risks posed by vibration, its effects on the individual and assessment and control of exposure. Source : Bad Vibes . Bamber, L. Health and...
Prolonged use of electric grass trimmer exposes the user to the risk of hand-arm vibration syndrome. A simple approach for the suppression of hand-arm vibration in electric grass trimmer is presented. The proposed system is a tuned vibration absorber (TVA). The results indicated that minimum vibration level was related to the position of the TVA on the shaft of electric grass trimmer. The tuned vibration absorber when installed to the electric grass trimmer attenuated the vibration total value by 67%. This significantly reduces the risk of hand-arm vibration syndrome. Source : Tuned vibration absorber...
This study investigated how reductions in finger blood flow depend on shock repetition rate and the peak and rms magnitude of acceleration. Different repetition rates (1.3-83.3 s(-1)) and different peak magnitudes (10-88 ms(-2) peak) but the same rms acceleration (10 ms(-2) rms) caused similar decreases in blood flow in fingers on exposed and unexposed hands. Shocks with a 83.3 s(-1) repetition rate, peak magnitude of 10 ms(-2) and rms acceleration of 10 ms(-2) provoked greater reduction in finger blood flow than shocks with the same peak magnitude but lower repetition rate (21 or 5.3 s(-1)) and...
To improve the reliability of the anti-vibration (AV) glove test defined in the current standard, a revised version of the standard has been proposed. This study examined the rationale behind the major revisions of the standard and evaluated the major technical aspects of the revised method through an experiment. To help evaluate the AV glove criteria, the effects of the glove on the grip strength were also examined. The glove vibration transmissibility values were measured with a new spectrum proposed in the current study. The results suggests the new spectrum can greatly simplify the test without...
Two employees in the weld destruct section where air chisels were used to undo welds on cars to test the strength of them developped Hand Arm Vibration Syndrome (HAVS) in December 2006. The subsequent investigation by HSE found that vibrating hand tools were being used across the plant with a lack of assessment and management of risk and when a health surveillance regime was then made effective, other cases came to light. There was no system in place to measure how long was being spent using the tools by each employee or the levels of vibration. The recommended amount of time for one of the tools...
La maladie de Dupuytren est une affection courante dont la prévalence varie de 4 à 10 % dans la population adulte, selon les études. Elle a pour conséquence une flexion irréductible d'un ou plusieurs doigts. Bien que généralement indolore, celle-ci peut générer un handicap majeur. 14 articles répondant aux critères de qualité prédéfinis ont été inclus dans une méta-analyse. Celle-ci retrouve une association significative entre le travail manuel et la maladie de Dupuytren ainsi...
Prolonged, intensive exposure to vibrations from palm and orbital sanders could cause finger disorders. They are associated with the biodynamic responses of the fingers. This study confirmed that the distributed hand responses generally varied with locations on each finger, vibration frequencies, and applied hand force. This study enhanced the understanding of the biodynamic responses of the fingers and hand exposed to vibrations on a contact surface with a large effective radius such as that found on palm and orbital sanders. These results are useful for developing hand and finger models required...
This study was to assess hand–arm vibration (HAV) exposure during different grinding operations, in order to obtain estimates of the variance components and to evaluate the effect of work postures. In the wheel wear test, the equivalent hand–arm-weighted accelerations for Grinder 1 during the first and second grinding minutes were 3.4 and 2.9 m s −2 , respectively, and for Grinder 2, they were 3.1 and 2.9 m s −2 , respectively. For Grinder 1, the equivalent hand–arm-weighted acceleration during the first grinding minute was significantly higher ( P = 0.04) than during...
The portable petrol driven grass trimmer is identified as a type of machine whose operator can be subjected to large magnitude of hand-arm vibration. The vibration total level on the handle of grass trimmer of 11.30 m/s 2 was measured, and it has reached the exposure limit value of 5.0 m/s 2 for daily vibration exposure A(8). Operators were not fully aware of the level of vibration. Different prototype handles were tested; one that is made of heavier material results in the lowest hand-arm vibration. The new handle has significantly reduced the vibration total value by 76% compare with the existing...
The work described in this report assesses the standard test for hedge trimmers defined in BS EN ISO 10517:2009 for repeatability and ease of use and where possible for reproducibility (by comparing machine manufacturers’ declared vibration against HSL measurements to the same standardised procedures). It also assesses the validity of the measurement techniques adopted in the vibration emission test, investigates some of the factors which are likely to influence the results of the test and compares the vibration emission values with vibration magnitudes measured under real operating conditions...
A full time tattoo artist posted a question on NIOSH Science Blog (#22): «i have been getting sever numbness and tingling in my finger it will last up to two to three days on times i am getting concerned about the effects the vibration of the tattoo machine may be causing». Amy Mobley and Renguang Dong of NIOSH answered: «The tattoo gun seems similar to some dental tools and it may generate high frequency vibration. At higher frequencies, the vibration-induced problems are mainly in the hand and fingers, such as finger tingling, numbness, pain, and white finger. » They said...
In recent years there have been many cases of HAVS being reported for people who work in agriculture, horticulture and landscape gardening. HSE/HSL does not currently hold much information on vibration exposures in these areas of work. The work described in this research report assesses the standard test defined in BS EN 836:1997 (incorporating amendments Nos. 1 to 3) for repeatability and ease of use and where possible for reproducibility (by comparing machine manufacturers' declared vibration against HSL measurements to the same standardised procedures). Source : http://www.hse.gov.uk/research...
Cheshire East Council was prosecuted by the Health and Safety Executive (HSE), United Kingdom, after a 56-year-old mechanic developed a severe form of hand arm vibration syndrome. Since 1984, the worker regularly used heavy-duty vibrating equipment, including pneumatic drills and hand-held grinders. The investigation inspector at HSE explained: "The worker was first diagnosed as developing hand arm vibration syndrome in 2005 but the council failed to take any significant action for nearly four years to stop the condition getting worse. The council should have limited the amount of time he...
Assessing past cumulative vibration exposure is part of assessing the risk of hand-arm vibration syndrome (HAVS) in workers exposed to hand-arm vibration and invariably forms part of a medical assessment of such workers. This study investigates the strength of relationships between the presence and severity of HAVS and different cumulative exposure metrics obtained from a self-reporting questionnaire. Use of simple years of exposure is a weak predictor of HAVS or its increasing severity. The calculation of cumulative hours across all vibrating tools used is a more powerful predictor. More complex...
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