Open AccessA proposal for a more refined single number rating system for hearing protector attenuation specification
Author(s) -
Warwick Williams
Publication year - 2012
Publication title -
noise and health
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.344
H-Index - 48
eISSN - 1998-4030
pISSN - 1463-1741
DOI - 10.4103/1463-1741.99897
Subject(s) - attenuation , computer science , standard deviation , rating system , reliability engineering , test (biology) , audiology , current (fluid) , statistics , mathematics , medicine , electrical engineering , engineering , paleontology , physics , environmental economics , optics , economics , biology
From a study of recent hearing protector attenuation test data, this work presents a proposal to reconsider how data, gathered by recognized standard subjective test procedures, is used to calculate the single number performance rating of hearing protectors. Current practice is to embed the expected performance (mean) and the variation in performance (standard deviation) in a single rating figure. A proposal is made for clearly separating expected performance from the variation while retaining the use of the current subjective test procedures. This proposal is applicable to all current single number rating systems including SNR, NRR, SLC(80), and the newer ANSI NRS(Ax).