For certain types of shocks, acute reductions in finger blood flow can be predicted from the rms acceleration.

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 lower rms acceleration (5 or 2.5 ms(-2)).

Source: Acute effects of mechanical shocks on finger blood flow: influence of shock repetition rate and shock magnitude. Ye Y, Mauro M, Bovenzi M, Griffin MJ. Int Arch Occup Environ Health. 2011 Oct 2.

http://www.ncbi.nlm.nih.gov/pubmed/21964880

Professional driving and prolapsed lumbar intervertebral disc diagnosed by magnetic resonance imaging

Objectives The aim of this study was to investigate whether whole-body vibration (WBV) is associated with prolapsed lumbar intervertebral disc (PID) and nerve root entrapment among patients with low-back pain (LBP) undergoing magnetic resonance imaging (MRI).
Methods A consecutive series of patients referred for lumbar MRI because of LBP were compared with controls X-rayed for other reasons. Subjects were questioned about occupational activities loading the spine, psychosocial factors, driving, personal characteristics, mental health, and certain beliefs about LBP. Exposure to WBV was assessed by six measures, including weekly duration of professional driving, hours driven at a spell, and current 8-hour daily equivalent root-mean-square acceleration A(8). Cases were sub-classified according to whether or not PID/nerve root entrapment was present. Associations with WBV were examined separately for cases with and without these MRI findings, with adjustment for age, sex, and other potential confounders.
Results Altogether, 237 cases and 820 controls were studied, including 183 professional drivers and 176 cases with PID and/or nerve root entrapment. Risks associated with WBV tended to be lower for LBP with PID/nerve root entrapment but somewhat higher for risks of LBP without these abnormalities. However, associations with the six metrics of exposure were all weak and not statistically significant. Neither exposure–response relationships nor increased risk of PID/nerve root entrapment from professional driving or exposure at an A(8) above the European Union daily exposure action level were found.
Conclusions WBV may be a cause of LBP but it was not associated with PID or nerve root entrapment in this study.

Source : http://www.sjweh.fi/show_abstract.php?abstract_id=3273

Some of the tested gloves meet the vibration transmissibility criteria specified in the current standard (ISO 10819,1996) but none of them could be classified as an AV glove

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 changing the original test results, and it should be adopted in the further revision of the standard. The results of this study also strongly support the proposed major revisions in the instrumentation and test  procedures. The glove that reduced the grip strength the least was also the one that reduced the most vibration, which suggests that the negative and positive effects of the glove can be balanced in its design. This study can significantly help improve the current standard on the test. The results of this study can also be directly used to help select appropriate AV gloves. 

Source : An evaluation of the proposed revision of the anti-vibration glove test method defined in ISO 10819 (1996). Welcome D.E. et al. International Journal of Industrial Ergonomics, 42 (2012) 143e155.

http://pdn.sciencedirect.com/science?_ob=MiamiImageURL&_cid=271473&_user=4494765&_pii=S0169814111001181&_check=y&_origin=browse&_zone=rslt_list_item&_coverDate=2012-01-31&wchp=dGLzVlS-zSkWA&md5=b18aa78fcdb316e20d7356706b91991e/1-s2.0-S0169814111001181-main.pdf

http://www.sciencedirect.com/science/article/pii/S0169814111001181

Suisse : succès impressionnant: depuis 1971, le nombre des lésions auditives est passé de 37 à 8 %

En Suisse, environ 200 000 personnes sont exposées, dans le cadre de leur activité professionnelle, à du bruit pouvant mettre en danger l'ouïe. Des stations d'examen mobiles ou audiomobiles se déplacent dans toute la Suisse pour examiner tous les travailleurs exposés au bruit dangereux pour l'ouïe dans le cadre de leur activité professionnelle, par exemple les ouvriers forestiers, les serruriers, les menuisiers, les agents de police et, depuis 1987, les musiciens d'orchestre. Les examens de contrôle réguliers, le conseil global dans les cinq audiomobiles, les mesures préventives dans le cadre de l'entreprise et les progrès techniques ont permis de réduire le pourcentage d’atteintes auditives de 37% à moins de 10 %. Cette tendance se manifeste également dans le taux de port des protecteurs d'ouïe. Au début du programme de prévention, 17 % seulement des personnes examinées portaient des protecteurs d'ouïe. Aujourd'hui, ce taux dépasse les 90 %.

Source : L'audiomobile: quatre fois moins de lésions auditives en 40 ans. La SUVA. Lucerne, 24. novembre 2011.

http://www.suva.ch/fr/startseite-suva/die-suva-suva/medien-suva/medienmitteilungen-suva/2011/40-jahre-audiomobile-viermal-weniger-gehoerschaeden/medienmitteilung-detail-suva.htm?WT.mc_id=nl98776&WT.email_id=23100&DCS.dcsref=/wttracking/23100.html&DCS.dcssip=www.suva.ch

Vibrations au corps entier : Les conducteurs de transpalettes électriques se portent mieux

Dans le cadre des travaux du Réseau prévention sur la limitation des vibrations au poste de travail, l’INRS a mené une étude portant sur les transpalettes électriques à conducteur porté. Une problématique que certaines entreprises prennent également en compte lors de l’acquisition de transpalettes. Le niveau de vibrations subies par le cariste dépend d’abord de l’engin qu’il conduit, mais également de l’état des sols, de sa posture, de sa façon de conduire.

Source : Travail et sécurité- INRS. Novembre 2011 no 722

http://www.travail-et-securite.fr/

http://www.travail-et-securite.fr/archivests/archivests.nsf/(alldocparref)/TS722page42_1/$file/TS722page42.pdf?openelement

Workload is elevated with whole-body vibration, without getting affected by backrest angle.

This study investigated the effects of reclined backrest angles on cognitive and psycho-motor tasks during exposure to vertical whole-body vibration. Apart from 22.5° seat backrest angle for the tracking task, backrest angle did not adversely affect the performance during vibration. However, participants required increased effort to maintain performance during vibration relative to the stationary condition. These results suggest that undertaking tasks in an environment with vibration could increase workload and risk earlier onset of fatigue.

Source: The influence of seat backrest angle on human performance during whole-body vibration. Paddan, G.S. et al. Ergonomics, Volume 55, Issue 1, 2012 pages 114-128. DOI: 10.1080/00140139.2011.634030

http://www.tandfonline.com/doi/abs/10.1080/00140139.2011.634030

Using a Starter Pistol, generates 166dB impulse noise (peak )at 0.5m

At the shooters ear a blocked barrel .22 caliber Starter Pistol produces significantly  higher sound pressure levels (7-18dB) than a comparable .22 caliber pistol, regardless of ammunition. Use of hearing protection is required for shooter. Closest athletes and potentially some spectators are at risk according to current NIOSH and WHO sound exposure guidelines. Using a Starter Pistol, which generates 166dB at 0.5m, the shooter will have to be 256 meters(!!) or ~280 yards away from the athletes to adhere to Electronic Starter requirements. Starter Pistols and/or Blanks are used for high school, university and pro athletics competitions but also dog training, acting, stage, film.

Impulse Noise Levels Generated by a .22 Caliber Starter Pistol. Sondergaard, J. et al.  Feb. 25^th 2011,  Conference proceedings of 36^th Annual Hearing Conservation Conference, NHCA

http://nhca.affiniscape.com/associations/10915/files/Sondergaard_Jacob_022511.pdf

http://nhca.affiniscape.com/displaycommon.cfm?an=1&subarticlenbr=119

Traitement acoustique des locaux de travail

Le local a un rôle déterminant dans l'exposition au bruit des travailleurs. Par sa réverbération, il augmente le bruit provenant des machines et affecte tout l'espace de travail. Le code du travail fixe les caractéristiques minimales que doivent présenter les locaux.
Ce document rappelle quelques aspects techniques, décrit comment qualifier un local, précise les exigences réglementaires et explique le principe et la mise en oeuvre du traitement acoustique d'un local. Ce document annule et remplace la fiche pratique de sécurité ED 136 "Améliorer l'acoustique des locaux de travail", publiée en 2009.

Source : http://www.inrs.fr/accueil/produits/mediatheque/doc/publications.html?refINRS=ED%206103

Bruit excessif, la CLP s'en remet à la définition du terme «excessif» que donne le dictionnaire

Le travailleur doit donc démontrer, non pas une exposition à un bruit important ou significatif, mais plutôt une exposition à un bruit «qui dépasse la mesure souhaitable ou permise, qui est trop grand, trop important». La présomption de maladie professionnelle s'applique puisque le travailleur a une atteinte auditive causée par le bruit et qu'il a été exposé à des bruits excessifs dans le cadre de son travail de mécanicien-assembleur de moteurs d'avions. Certaines mesures réalisées chez l'employeur jusqu'en 1994 sous-estiment l'exposition réelle du travailleur, car elles ont été effectuées avec un facteur de bissection de Q=5, selon la norme OSHA, alors que si ces études avaient été faites avec la norme ISO, dont le facteur de bissection est de Q=3, les niveaux de bruits seraient plus élevés, norme que privilégie le tribunal: Pratt & Whiyney Canada et Émond, 2011 QCCLP 4313, [2011] C.L.P. 248.

http://www2.clp.gouv.qc.ca/sites/clpq/memento05.nsf/852562dd006ae370852562760073c65a/f0efb2fbb06acf59852578b500663c40!OpenDocument

Bridge the gap between traditional hearing protection and communication.

The hearing capabilities of a worker are very important for communication, gaining situational awareness, and reducing the risk of other hazards or injury. However, understanding communications in extreme noise and at work sites is always challenging while wearing hearing protection. Too much protection and a worker cannot hear and is vulnerable to other safety hazards. Too little protection, and the worker is inadequately protected and at a higher risk for noise-induced hearing loss. For those who seek to bridge the gap between traditional hearing protection and communication, the technology now exists to intelligently protect and connect workers in extreme environments. In this article, we will examine the growing segment of intelligent hearing protection technologies that offer a variety of passive and active technologies, and better understand their applications in industrial workplaces.

Source: Intelligent Hearing Protection. Renée S. Bessette, Occupational Health and Safety, october 2011.

http://ohsonline.com/articles/2011/10/01/intelligent-hearing-protection.aspx?sc_lang=en

Occupational Health & Safety Magazine Digital Edition: The OH&S Magazine Digital Edition is a downloadable version of the print magazine.
If you're not already a member, please sign up using the register button in the upper-right of the page. Registration and download are FREE.

http://ohsonline.com/resarch/list/occupational-health-safety-magazine-digital-edition.aspx

Employees affected by the vibrations of air chisels : The UK vehicule manufacturer was prosecuted.

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 to be used was one hour per day per person, but it had been in use for three hours per day. In all, ten employees were thought to be affected by ill health attributable to the use of vibrating hand tools at the Solihull plant. Vehicle manufacturer Land Rover has been prosecuted by the Health and Safety Executive for failing to take into account the risks associated with workers at its Solihull plant using vibrating hand tools.

Source : Land Rover fined for failing to assess risk. 27 April 2011. HSE Release No: WM420/11.

http://www.hse.gov.uk/press/2011/coi-wm-42011.htm#?eban=rss-vibration

Damper with optimised progressive damping characteristic is better at shock mitigation than suspended commercial seat as presently available

A single degree-of-freedom simulation model of a seat equipped with a non-linear fore-and-aft suspension system was developed. The performance of a typical fore-and-aft suspension system was analysed using typical vibration and shock acceleration signals measured in loaders while travelling on off-road terrain and while driving the bucket into a heap of soil. The simulations are of use to seat manufacturers in developing improved fore-and-aft seat suspension for wheel loaders.

Source:  Study of simultaneous shock and vibration control by a fore-and-aft suspension system of a driver’s seat. G.J. Stein, P. Múčka. International Journal of Industrial Ergonomics, Volume 41, Issue 5, September 2011, Pages 520-529.

doi:10.1016/j.ergon.2011.03.003

http://www.sciencedirect.com/science/article/pii/S0169814111000424011

High-frequency audiometry is more sensitive to detect noise-induced hearing loss than conventional audiometry

Early diagnosis of NIHL can help prevent the progression of hearing loss, especially in speech frequencies. This study compared hearing threshold and prevalence of hearing loss in conventional and high frequencies of audiometry among textile workers. Hearing loss was more common in HFA than conventional audiometry. HFA is more sensitive to detect NIHL than conventional audiometry. It can be useful for early diagnosis of hearing sensitivity to noise, and thus preventing hearing loss in lower frequencies especially speech frequencies.

Source : High-frequency audiometry: A means for early diagnosis of noise-induced hearing loss. Mehrparvar, A.H. et al. Noise and Health, 2011, 13, 55, pp. 402-106. DOI: 10.4103/1463-1741.90295

http://www.noiseandhealth.org/article.asp?issn=1463-1741;year=2011;volume=13;issue=55;spage=402;epage=406;aulast=Mehrparvar;type=0

Stress and difficulty communicating in the chemotherapy clinic

This study measured the noise levels in the Portland Veteran's Affairs Medical Center's outpatient chemotherapy clinic. Patients, visitors, and staff members filled out anonymous surveys regarding their reactions to noise levels. Noise measurement analysis indicated that levels were at or above 70 dB SPL for less than ten minutes during the 11-hour recording window. The patient and visitor surveys indicated that both groups were unbothered by noise in the clinic. However, most staff members were bothered by or concerned about noise levels, and many felt that it caused stress and difficulty communicating on the phone.

Source : Ambient noise levels in the chemotherapy clinic. Gladd, D.K., Saunders, G.H. Noise and Health, 2011, 13, 55, pp. 444-451. DOI: 10.4103/1463-1741.90322

http://www.noiseandhealth.org/article.asp?issn=1463-1741;year=2011;volume=13;issue=55;spage=444;epage=451;aulast=Gladd;type=0

L’exposition cumulée élevée à des forces ou vibrations transmises au membre supérieur est associée à la survenue de la maladie de Dupuytren.

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 que l'exposition aux vibrations. L'existence d'autres facteurs de risque, notamment une prédisposition génétique, n'est pas suffisante pour remettre en cause cette relation potentiellement causale avec les conditions de travail. En conclusion, une association entre  l'exposition cumulée  élevée aux contraintes physiques (force ou vibrations transmises au membre supérieur) est associée à la survenue de la maladie de Dupuytren.

 Source : La maladie de Dupuytren peut-elle être d'origine professionnelle ? Revue et méta-analyse d'un vieux débat.  Descatha A, Jauffret P, Chastang J-F, Roquelaure Y, Leclerc A. Should we consider Dupuytren's contracture as work-related ? A review and meta-analysis of an old debate. BMC Musculoskelet Disord. 2011 ; 12 : 96. Période : mars 2011 à août 2011

Tiré de Anses, Bulletin de veille scientifique no 16, Santé / Environnement / Travail, Décembre 2011, p.36.

http://www.afsset.fr/upload/bibliotheque/696336679257124840838621917145/Anses_bulletin_veille_scientifique_16_BVS_16.pdf