Méthode de mesures terrain de l'atténuation F-MIRE de protecteurs auditifs durant un quart de travail

Abstract

Nowadays, hearing protection devices (HPD) are widely used to protect workers against industrial noise, however, a question worth examining is: "Is the worker truly provided with, at all times, protection that is as effective as what the manufacturer is advertising, based on standardized testing?" It is a commonly known and well documented fact that compared to values obtained from various existing field studies laboratory-measured noise attenuation values overestimate the actual protection being provided to workers. Too few studies are available on this topic, and the issues concerning HPD field measurement are still far from being resolved. Even if several field measurement methods have been developed, none has succeeded in being recognized as a standard. Therefore, the need for a new field measurement method, one which could become a recognized reference, is as relevant as ever. This paper presents a new field measurement method developed to quantify the in-field attenuation HPDs provide to workers. This method is designed to take ongoing measurements during a complete work shift (8 hours) and enable the measurement of the actual attenuation being provided to the worker in his work environment, for different types and levels of industrial noise. The measurement method is based on the F-MIRE protocol using a miniature double microphone that allows for simultaneous measurement of the sound pressure inside the protector and the sound field surrounding the worker. The time signals recorded are then analyzed in order to determine the overall protection, and also, to assess performance over time. Results from preliminary measurements obtained from factory workers are presented in order to fully illustrate the range of analysis possibilities of this new field measurement method.