At the present time, approximately half a million Québec workers are exposed daily to noise levels capable of causing hearing problems, and some of them are dealing with the consequences of occupational deafness. While the elimination of noise at source is the most effective solution, it is sometimes impossible to do it, and the use of personal means of hearing protection is then necessary.

However, there are problems associated with the wearing of hearing protectors; they can mainly cause communication difficulties, and can be a risk cofactor for occupational accidents. Because it is difficult to choose and design an adapted hearing protector, they may not properly protect the user and may represent a risk to his hearing health. Due to the discomfort they cause, the recommended wearing time to limit noise exposure is not always respected. Finally, protector design is often based on empiricism without the optimization of performance and comfort.

The primary objective of this study is to develop tools and methods of measurement in order to better evaluate and improve the acoustical performances of hearing protectors, while integrating certain parameters that have an impact on comfort. The study includes the three types of protectors commonly used: ear muffs, ear plugs, and the dual protection consisting of the simultaneous use of ear muffs and ear plugs.