Evaluation of Different Criteria for Significant Threshold Shift in OccupationalHearing Conservation Programs

摘要

A comparison was undertaken of six different criteria for determinig significanthearing threshold shift. Each criterion was applied to the first eight audiograms for males participating in 15 different industrial hearing conservation programs. Of the different criteria used, the OSHA STS criterion produced the lowest overall percentage of employees tagged as having suffered a threshold shift. The 15-dB SHIFT and NIOSH SHIFT criteria produced the highest percentages. The mean percentages of employees tagged on an annual basis generally were small, less than 10 percent in referent data bases and 20 percent or less in the noncontrol data bases. The 15-dB SHIFT and NIOSH SHIFT criteria tagged 37 percent and 51 percent of employees in noncontrol data bases on the first test comparison and averaged 14 percent and 24 percent of employees even in referent data bases. The purpose of the significant threshold shift criterion was to tag employees with temporary threshold shifts (TTS) before they develop hearing loss. Therefore, the purpose of the threshold shift criterion selected was not to act as a recordable occupational illness but rather to reflect a significant amount of persistent hearing change.