Thesis - campus only access
Date of Award
Master of Science (MS)
Communication Sciences and Disorders
The purpose of this study was to determine the effects of agricultural noise on farm workers' auditory thresholds before and after a work day's exposure during the harvest season. Twenty volunteer subjects from a small farming community in North Central Kansas were selected for this study. Ten subjects served as the control group and 10 subjects served as the experimental group. The control group subjects were not exposed to agricultural noise during the harvest season on a daily basis. The experimental group subjects considered farming their main occupation and were exposed to agricultural noise during the harvest season on a daily basis. Pure tone thresholds for 500-8000 Hz were obtained from all subjects during six different testing situations, before harvest baseline, pre and post exposure testing on two consecutive days, and after harvest baseline. The subjects also completed a hearing health questionnaire. A speech discrimination test was given to each subject during the before harvest baseline, post exposure testing on Day # 1, post exposure testing on Day #2, and after harvest baseline testing. The results showed that the experimental subjects as a group showed a greater decrease in hearing sensitivity during the post exposure test situation, with the greatest number of subjects showing a decrease in hearing sensitivity during the post exposure testing of Day #2. The control subjects as a group did not show a significant change during any particular test situation. The experimental subjects showed greater difficulty with the speech discrimination test. The experimental subjects as a group reported lower speech discrimination scores during the post exposure testing on Day #2. It can be concluded from this study that the various types of agricultural equipment that farmers are exposed to do effect the farmer's hearing sensitivity. It was observed that the sound pressure measurements that were obtained showed that most of the farm equipment did exceed the 90 dB occupational noise standard established by the Occupational Safety and Health Administration. This finding, as well as the temporary threshold shifts that were observed, suggest that farmers are exposed to noise levels that are likely damaging to their hearing. As a result, farmers need to be more aware of safety precautions that should be taken before they are exposed to agriculture noise levels that are potentially damaging to their hearing.
Wolters, Shari A., "An Investigation of Temporary Hearing Threshold Shifts During the Harvest Season" (1997). Master's Theses. 2663.
Copyright 1997 Shari A. Wolters