Real-ear attenuation of hearing protection in young children

Abstract

Much attention has been focused in the past decade on the possibility that children and adolescents 6-19 years of age may experience noise-induced hearing loss (NIHL) due in part to high-level sound exposure during recreational, hobby, and employment activities. One of the strategies that is utilized to reduce the potential of experiencing NIHL is to wear hearing protection (earplugs and/or earmuffs) when exposed to hazardous noise levels. Currently, many parents rely upon adult-sized hearing protectors for use by their children and even though performance on adults has been measured since the 1950s, the effectiveness of smaller-sized products for children is unknown. This paper examines the feasibility of conducting standardized realear-attenuation-at-threshold (REAT) measurements with children of 5-10 years of age, and presents the results achieved with three types of hearing protectors (slowrecovery foam and premolded three-flange earplugs, and earmuffs) measured according to ANSI S12.6-2008. The Method A and B procedures were modified so that rather than the subject (child), the inexperienced parent served as the person inserting the hearing protector. Attenuation metrics are reported in terms of the Noise Reduction Rating (NRR) and 1/3 octave-band attenuation values for each protector. Differences between the three fitting conditions; Trained Parent (Method A), Untrained Parent (Method B) and Expert fit are highlighted. Values are also compared to those found for similar protectors fitted on adults.