Testing the efficiency of attenuating acoustic impulse noise in conditions of simultaneously used earmuffs and earplugs

The aim of the task was to test and assess the efficiency of attenuating acoustic impulse noise through so-called double protection, i.e., simultaneous use of earmuffs and earplugs placed in the external ear canal.The complexity of the problem of attenuating noise with double protection was analysed within the framework of the task. Numerous studies, which however refer to continuous noise only, indicate that noise reduction under double protection is lower than an algebraic sum of the noise reduction values of individual protectors. Measurements of impulse noise attenuation with individual protectors (i.e., earmuffs or earplugs) were conducted, too, as were measurements of attenuation with the same protective equipment used together.The test results have been included in the developed recommendations related to the use of double protection against acoustic impulse noise and in the information and training materials for employers, management and OSH services.