The effect of environment upon rate of recovery from temporary auditory threshold shift induced by small arms fire

This study was undertaken to determine the effect of various degrees of quiet on recovery from a temporary auditory threshold shift induced by gunfire from a .22 calibre rifle. The experiment was performed with twelve subjects. The procedure included an audiometric test before firing, exposure to gunfire at target practice, a second audiometric test to determine hearing loss immediately after target practice, and a third audio-metric test after a two hour period of exposure to either a quiet or a normal environment to determine the effect of each on hearing recovery. The null hypothesis which held that environment does not affect the rate of recovery was tested statistically by the analysis of variance. The analysis of variance supports the null hypothesis. Noise in the normal environment following a subject's exposure to gunfire from a .22 calibre rifle at target practice did not influence the recovery from the temporary auditory threshold shift. The number of subjects and using only two degrees of environmental noise limits the application of the results obtained from the experiment.