Pilot Study to Determine Maximum Permissible Ambient Noise Levels (MPANLs) and Suitable Headphone Type for Open Space Audiometric Test

The limited availability of audio booths and the lack of skilled operators result in limited access to audiometric testing. In fact, according to data from the World Health Organization (WHO) in 2050, around 700 million people will need rehabilitation to overcome a hearing loss that can 'paralyze' them. This pilot study investigated the ability of two types of headphone attenuation for clinical testing outside the audio booth to approximate the ANSI/ASA S3.1-1999 (R2018) standard Maximum Allowable Ambient Noise Levels (MPANLs) at specific test frequencies applied to room audiometry. Headphone attenuation and ambient noise reference capability for audiometers were evaluated by comparing air conduction thresholds in the laboratory in response to noise interference provided through omnidirectional speakers up to 4 reference levels (28 dBA, 38 dBA, 48 dBA, 58 dBA). The study started in a small sample as a pilot study of 3 subjects with normal hearing (age range 19 - 58 years; mean age 25.7) who were tested using insert-type headphones (wired and wireless) with passive and active attenuation. The results of the study concluded that there was no statistically significant increase in headphones with passive noise canceling until the ambient noise reference reached 58 dBA. However, it is different from active noise canceling, which has increased at those reference level.