Temporary threshold shift due to recreational firearm use

Objective: To assess whether a temporary threshold shift occurred after recreational firearm use. Design: An observational study of 25 subjects using ear protection in an indoor rifle range. Hearing was evaluated before and after shooting five rounds with a 0.22 calibre rifle over 10 minutes. A threshold shift of 5 dB was found to be statistically significant, while a shift of 10 dB; was clinically significant. Results: Twenty-four candidates had a statistically significant threshold shift, while 12 had a clinically significant threshold shift. Two subjects with previous industrial noise exposure had threshold shifts at more frequencies than other subjects. There was no significant preference for either ear. One subject showed no changes. Conclusion: This small study sheds some light on impulse noise behaviour in an indoor shooting range, but no definite conclusions can be drawn. The side of shooting did not influence threshold changes in either ear.