Evaluating manufacturing environment soundscapes

Abstract

This work presents an investigation into the soundscape of a large, industrial manufacturing plant in Lincoln, Nebraska, including exploration of the noise reduction performance of sound enclosures. Occupational noise-induced hearing loss is among the most common nonfatal work-related injuries and illnesses in the U.S., and most efforts to reduce this exist as limited noise exposure times and mandatory use of hearing protection devices. This research aims to develop knowledge of factory soundscapes and explore acoustical strategies to reduce noise near the source. The factory in this study uses two distinct types of sound enclosures on site: rigid box-style enclosures and resilient curtain-style enclosures. Using state-of-the-art technology, it was possible to better understand contributions of single noise sources to the complex, overall soundscape and evaluate some detailed acoustical characteristics of the noise. The measured data are compared with subjective assessment of company employees using methods described in Part 2 of the Soundscape Standard (ISO/TS 12913-2). Results presented include a noise reduction comparison of the two types of enclosures, a relationship between noise reduction and source-enclosure proximity, and a comparison between measurements and survey data.