Determination of the attenuation of earmuff active noise control devices applied to the protection, communication, and entertainment

Abstract

In this work a detailed analysis for determining the performance in noise reduction of three types of active noise cancellation hearing devices, which are applied to the protection, communication and entertainment is presented. This work was done using three standards available as references: a European (SS-EN 352-4), American (ANSI/ASA S12.42-2010) and the international one (ISO 4869-6). These standards provide all of the technical, theoretical, and practical specifications to evaluate the performance of hearing protectors. It will also be presented two of the methods commonly used to evaluate the performance of these devices: the objective method, microphone in real ear MIRE, and the subjective method, called real ear attenuation at threshold REAT. The operating principle of such devices is also discussed. Finally, a comparative analysis with previous works reported in the literature is presented.