Abstract
Noise levels recorded during performance tests conducted at the College of Agriculture, University of Nebraska, on 58 new tractors and 20 other types of farm machinery were of such intensity, duration, and distribution as to indicate a potential permanent noise-induced hearing loss to the agricultural worker. Of the tractors tested at 75% of full load, 90% exceeded the recommended 85-dB average level for the three octave bands centered at 500, 1000, and 2000 cps. Of the 20 pieces of special farm equipment tested, 65% exceeded this recommended level. The average overall sound pressure level for all models, types, and operator positions was 103.5 dB.
