Personal noise dosimeters: Accuracy and reliability in varied settings

This study investigated the accuracy, reliability, and characteristics of three brands of personal noise dosimeters (N = 7 units) in both pink noise (PN) environments and natural environments (NEs) through the acquisition of decibel readings, Leq readings and noise doses. Acquisition periods included repeated PN conditions, choir room rehearsals and participant (N = 3) Leq and noise dosages procured during a day in the life of a music student. Among primary results: (a) All dosimeters exhibited very strong positive correlations for PN measurements across all instruments; (b) all dosimeters were within the recommended American National Standard Institute (ANSI) SI.25-1991 standard of ±2 dB (A) of a reference measurement; and (c) all dosimeters were within the recommended ANSI SI.25-1991 standard of ±2 dB (A) when compared with each other. Results were discussed in terms of using personal noise dosimeters within hearing conservation and research contexts and recommendations for future research. Personal noise dosimeters were studied within the contexts of PN environments and NEs (choral classroom and the day in the life of collegiate music students). This quantitative study was a non-experimental correlation design. Three brands of personal noise dosimeters (Cirrus doseBadge, Quest Edge Eg5 and Etymotic ER200D) were tested in two environments, a PN setting and a natural setting. There were two conditions within each environment. In the PN environment condition one, each dosimeter was tested individually in comparison with two reference measuring devices (Ivie and Easera) while PN was generated by a Whites Instrument PN Tube. In condition two, the PN procedures were replicated for longer periods while all dosimeters measured the sound levels simultaneously. In the NE condition one, all dosimeters were placed side by side on a music stand and recorded sound levels of choir rehearsals over a 7-h rehearsal period. In NE, condition two noise levels were measured during a day in the life of college music students. Three participants each wore two types of dosimeters for an 8-h period during a normal school day. Descriptive statistical analyzes including means, standard deviation and Pearson product-moment correlation. The primary finding is that the dosimeters in this study recorded results within ±2 dB of either a reference measurement or within dosimeters in all four conditions examined. All dosimeters studied measured steady noise source accurately and consistently, with strong positive correlations across all instruments. Measurements acquired during choral rehearsals indicated a maximum of 1.5 dB difference across dosimeters. The Etymotic research personal noise dosimeters (ER200D) could provide individuals and schools of music with a relatively inexpensive tool to monitor sound doses. Findings from this study suggest that the three brands of dosimeters tested will provide reliable Leq levels and hearing dosages in both PN and natural settings.