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Efficacité des protecteurs auditifs
Les protecteurs individuels contre le bruit (PICB) peuvent être utilisés en complément des moyens de prévention collective contre les nuisances sonores. L'atténuation des bruits apportée par ces équipements est mesurée en laboratoire suivant certaines normes. Des méthodes commerciales existent afin d'évaluer l'atténuation fournie par les PICB sur le lieu de travail. L'INRS a étudié la précision de 4 systèmes commerciaux par rapport aux méthodes de référence...
Measuring the acoustic response of a compartment fire
Rescue teams have a small window of time to locate a downed firefighter. Their task is made more difficult due to low visibility, smoke, toxic gases, and high temperatures. In the United States, most firefighters are equipped with a Personal Alarm Safety System (PASS) device that emits an alarm sound, when the firefighter becomes incapacitated. Rescue teams can then follow this sound to the source to locate the downed firefighter. While the PASS device has been enormously successful, anecdotal evidence has shown it fails in some interesting scenarios. For example, cases have been recorded where...
Hearing Loss and Use of Hearing Protection Among Career Firefighters in the United States
Objective : To determine the prevalence and characteristics of noise-induced hearing loss (NIHL) and the use of hearing protection devices (HPDs) among career firefighters. Methods : A Web-based survey and a standard audiometric test were performed with 425 firefighters from three states in the United States. Results : More than 40% showed hearing loss in the noise-sensitive frequencies (4 and 6 kHz). The left ear showed significantly poorer hearing than the right ear. Firefighters having longer years of work in fire services demonstrated significantly worse hearing. Reported use of HPDs was 34...
The Importance of Properly Fitting Hearing Protection
Hearing loss is the No. 1 sensory disability in the world, and the World Health Organization estimates that 16 percent of hearing loss worldwide is attributable to occupational noise exposure. To minimize the risk of incurring hearing loss due to noise, it is important for organizations, employers and individuals to understand how they can better protect themselves and their employees from excessive noise in the workplace. Source : http://ehstoday.com/hearing-protection/importance-properly-fitting-hearing-protection
NIOSH HPD Well-Fit™: The Future is Fit-Testing
For workers and others who are exposed to dangerously loud noises which cannot be reduced or eliminated, hearing protection devices (HPDs) are absolutely necessary to save their hearing. But if HPDs are not properly selected or correctly worn, the devices may not block out enough noise and the wearer may still risk a loss of hearing. How can a person tell if their HPDs are fit correctly? A new development from NIOSH – HPD Well-FitTM – can quickly and inexpensively test the performance of hearing protection. This fit testing technology is a huge advancement in efforts to save workers'...
Panels Manufactured from Vegetable Fibers: An Alternative Approach for Controlling Noises in Indoor Environments
Noise control devices such as panels and barriers, when of high efficiency, generally are of difficult acquisition due to high costs turning in many cases their use impracticable, mainly for limited budget small-sized companies. There is a huge requirement for new acoustic materials that have satisfactory performance, not only under acoustic aspect but also other relevant ones and are of low cost. Vegetable fibers are an alternative solution when used as panels since they promise satisfactory acoustic absorption, according to previous researches, exist in abundance, and derive from renewable sources...
The Balancing Act: New Hearing Conservation Technology as Functional Enablers
Strike a balance between protecting workers' hearing and helping them maintain situational awareness and the ability to communicate. In this article, we will review the options hearing managers can employ to strike an appropriate balance among the challenges of achieving hearing protection, situational awareness and two-way communication. Source : http://ehstoday.com/hearing-protection/balancing-act-new-hearing-conservation-technology-functional-enablers
Clamping force and increased bulk increases discomfort and wearing difficulty for circum-aural hearing protectors
The physical properties of circum-aural hearing protectors, such as mass, clamping force and cup volume, have an influence on the attenuation performance of the device. This paper closely examines the physical and acoustic properties 39 of hearing protectors readily available to all users. The results indicate that attenuation increases with clamping force up to a limiting value of around 11 Newtons above which expected increases in attenuation are very small for large increases in clamping force. Likewise increasing the (newly introduced term) bulk of a hearing protector (volume, mass and cup...
Support and determination to get accustomed to hearing protector use are important factors in hearing conservation for musicians.
Despite a high level of sound exposure and a fairly large selection of earplugs available, musicians have often been reported to use personal hearing protectors only seldom. Musicians reported that earplugs hampered listening to their own and their colleagues' playing; earplugs affected either timbre or dynamics, or both. Additionally, several reasons related to discomfort of use were itemized. The research therefore tested subjects. With the REAT procedure, the values obtained in sound field were relatively close to the manufacturer's nominal specifications. Then, subjects were tested...
Less overall comfort of insert earplugs is associated with an increase in attenuation.
Noise-induced hearing loss is almost always preventable if properly fitted hearing protectors are worn to reduce exposure. Many individuals choose not to wear hearing protection because it may interfere with effective communication in the workplace or it may be uncomfortable. Hearing protector comfort has not received the same amount of attention as noise reduction capability. The present study was conducted to evaluate the comfort level of two different types of insert earplugs as well as the attenuation levels achieved by the earplugs. Attenuation levels were obtained with a commercially available...
Safety professionals cannot simply rely on the NRR found on hearing protector labeling!
For the first time in more than 30 years, the Environmental Protection Agency is set to update its regulations concerning hearing protection devices. Although many stakeholders are pleased that EPA is attempting to update the rule, some have expressed concern that the update may not make things clearer for the end user – and that could lead to problems. Using a range of NRR numbers instead of one number could make it more complicated for safety professionals to choose the right device, he said. “There just isn't any lab-based number we can put on a product that can tell you what...
La modélisation par éléments finis pour l’amélioration de la conception acoustique des protecteurs auditifs.
Il s’agit d’une étude exploratoire visant à examiner le potentiel de la modélisation par éléments finis à traiter le problème de la transmission sonore à travers les protecteurs auditifs. Dans le cas des bouchons, le modèle permet de bien représenter la physique du problème sur une grande partie de la gamme de fréquences. Dans le cas des coquilles, le modèle fournit des tendances acceptables pour les deux types d’excitation (acoustique et mécanique), mais il existe des écarts...
Quand et comment avoir recours à un double protecteur auditif ?
Réponse de l'INRS à la question suivante : À partir de quel niveau de bruit d'exposition peut-on conseiller le port d'un double protecteur auditif ? Comment peut-on estimer l'efficacité d'une double protection ? Comment en déduire le niveau de bruit résiduel sous le protecteur pour le comparer aux valeurs limites d'exposition ? par A. Kusy Source : Dans la section Questions-Réponses http://www.dmt-prevention.fr/inrs-pub/inrs01.nsf/IntranetObject-accesParIntranetID/OM:Rubrique:47889EFF1CAA7BABC1256F5B003B9090/$FILE/Visu.html
State of the Art in Hearing Protection Research is Addressed by NIOSH Scientists in Special Journal Issue
Leading experts from the National Institute for Occupational Safety and Health (NIOSH) contribute to this month's special issue of the peer-reviewed journal Noise and Health on state-of-the-art research on hearing protection devices. The March-April issue of Noise and Health is available online at www.noiseandhealth.org . The articles present latest findings in areas where new research is vital for addressing challenges that practitioners, employers, and workers can face in choosing and using proper hearing protection. These include: •Proper fit testing of hearing protectors. •Determining...
Transmission sonore à travers les protecteurs auditifs et application d'une méthode pour évaluer leur efficacité en milieu de travail
La réduction du bruit à la source est la solution à privilégier pour combattre les effets du bruit en milieu de travail. Malgré tout, de par sa simplicité à mettre en oeuvre à par son apparent faible coût, l'utilisation de protecteurs auditifs demeure très populaire. Il devient donc important de bien connaître l'efficacité réelle des protecteurs utilisés en milieu de travail afin de faire des choix judicieux et éclairés. Cependant, de nombreuses études au cours des vingt...
RR727 - Market surveillance of custom-moulded earplugs
A study of a selection of CE-marked custom-moulded earplugs available in the UK was carried out in order to examine the protection provided by such devices, and to identify any influencing factors on protection, comfort and fit. Source: http://www.hse.gov.uk/research/rrhtm/rr727.htm?ebul=noise/nov09&cr=1
Real world use and performance of hearing protection
This report considers the effectiveness of hearing protectors in everyday work situations. The study reported here was undertaken in two parts. The first consisted of interviews with employers to discuss management of noise and hearing protector use, and on site observation of hearing protector use. The second part was objective laboratory measurements of hearing protector insertion loss. The purpose of these measurements was to quantify the reduction in protection due to poor fitting or maintenance for a range of hearing protectors. Earmuffs were tested using the MIRE (microphone in real ear)...

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