Use of historical data and a novel metric in the evaluation of the effectiveness of hearing conservation program components

• Published in: Occupational and environmental medicine (London, England) England), 2011-07, Vol.68 (7), p.510-517
• Main Authors: Heyer, Nicholas, Morata, Thais C, Pinkerton, Lynne E, Brueck, Scott E, Stancescu, Daniel, Panaccio, Mary Prince, Kim, Hyoshin, Sinclair, J Stephen, Waters, Martha A, Estill, Cherie F, Franks, John R
• Format: Article
• Language: English
• Subjects: Acoustic data; Acoustic noise; Adult; Audiometry; Audiometry, Pure-Tone; Automobiles; Biological and medical sciences; Continuous noise; Ear Protective Devices - utilization; Effects of various physical factors on living matter (vibrations, electric field, ultrasound, sound...); Environmental Monitoring - methods; Epidemiologic Methods; Epidemiological Monitoring; epidemiology; Female; Focus groups; Food Handling; Foreign exchange rates; Fundamental and applied biological sciences. Psychology; Gender differences; hearing; Hearing conservation; hearing conservation programs; Hearing loss; Hearing Loss, Noise-Induced - etiology; Hearing Loss, Noise-Induced - prevention & control; Hearing protection; hearing protective devices; Humans; Information retrieval noise; Male; Middle Aged; Noise; Noise induced hearing loss; Noise intensity; Noise levels; Noise measurement; Noise reduction; Noise, Occupational - adverse effects; Noise, Occupational - prevention & control; Occupational Diseases - etiology; Occupational Diseases - prevention & control; Occupational Exposure - adverse effects; Occupational Exposure - analysis; Occupational hazards; Occupational Health Services - methods; Occupational Health Services - standards; PPE; Program Evaluation; Quality; Quality Assurance, Health Care; Studies; Tissues, organs and organisms biophysics; Workers; Workplace
• ISSN: 1351-0711; 1470-7926
• DOI: 10.1136/oem.2009.053801

ObjectivesTo evaluate the effectiveness of hearing conservation programs (HCP) and their specific components in reducing noise-induced hearing loss (NIHL).MethodsThis retrospective cohort study was conducted at one food-processing plant and two automotive plants. Audiometric and work-history databases were combined with historical noise monitoring data to develop a time-dependent exposure matrix for each plant. Historical changes in production and HCP implementation were collected from company records, employee interviews and focus groups. These data were used to develop time-dependent quality assessments for various HCP components. 5478 male (30 427 observations) and 1005 female (5816 observations) subjects were included in the analysis.ResultsAnalyses were conducted separately for males and females. Females tended to have less NIHL at given exposure levels than males. Duration of noise exposure stratified by intensity (dBA) was a better predictor of NIHL than the standard equivalent continuous noise level (Leq) based upon a 3-dBA exchange. Within this cohort, efficient dBA strata for males were