2022 NHCA Annual Virtual Conference

The last 50 years have witnessed regulatory, technological, and demographic changes that impact occupational hearing conservation programs (HCPs) in the U.S. This presentation describes trends in threshold shifts observed in a database of over 600,000 exams (> 140,000 workers) between 1970 and 2020. Unadjusted rates of standard threshold shifts (STS) declined from over 50% of tested workers through the 1980s to 13% from 2010-2019. Recently, the median time from baseline to initial STS trigger was around 2 years; 25% of initial STS trigger events occurred in year 1. Given the short time between baseline and initial STS triggers, enhanced efforts to identify problems in the first few years in the hearing conservation program (e.g., insufficient education and training; inadequate hearing protector selection, fitting, or use; inadequate engineering controls) could lead to additional reductions in rates of threshold shifts among noise exposed workers.